Tuesday, October 13, 2009
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Slash Your Power Bills by 80% Or Even Eliminate Them Completely
Slash Your Power Bills by 80% Or Even Eliminate Them Completely
Slash Your Power Bills by 80% Or Even Eliminate Them Completely
Slash Your Power Bills by 80% Or Even Eliminate Them Completely
Slash Your Power Bills by 80% Or Even Eliminate Them Completely
What if I told you, that by purchasing all the components individually and assembling it yourself, you can put together a complete system for less than $200 and start generating your own power right now. In fact, that's exactly what I've discovered. After years of extensive testing and development, the Power4Home plans are available to everyone.
I'll teach you everything you need to know about generating your own electricity using wind and solar power. The Power4Home system includes easy-to-follow, fully illustrated manuals that explain everything in complete detail.
Plus, I've included video instructions that you can follow along with step-by-step that make generating your own electricity absolutely foolproof.
Listen, we all have to do our part in saving our environment and I want to make sure as many people as possible start generating their own power at home. Whether you want to reduce your electricity bill, eliminate it completely or even start getting paid for the extra electricity you generate, the Power4Home system is the solution you've been looking for.
Why Pay $1000's For Wind And Solar Power Systems When You Can Build Your Own Professional System For Less Than $200!
Home wind and solar power systems have been on the market for years. These systems work great, the only problem is that they'll cost you a few thousand dollars. This is the main reason this technology isn't in everyone's home.But that was just the beginning. After I began to tune the system to make it more energy-efficient, my typical utility bill was slashed by more than 80% (some months I even had a surplus of electricity, which not only gave me an electric bill of $0, it allowed me to sell my extra juice back to the power company—where they paid me instead!)
Well, at this point I realized that millions of people could benefit from what I had accomplished. But I had to figure out a way to build it inexpensively, using well-laid out plans that even non-techie's could read and use. Finally, I had to make sure it was safe and foolproof.
Perhaps even something that a father and son could build for themselves in a short weekend.
Well, it took some time, but eventually a friendlier more efficient version of the Power4Home System was born.
With it, I can help you slash your power bill by 80% or even eliminate it completely.
And remember the kicker: if you generate more energy than you use, the electricity company will pay you!
See, I've taken everything I've learned over the years and put together a kit that shows you exactly how to create electricity in your own backyard
I'll teach you everything you need to know about generating your own electricity using wind and solar power. The Power4Home system includes easy-to-follow, fully illustrated manuals that explain everything in complete detail.
Plus, I've included video instructions that you can follow along with step-by-step that make generating your own electricity absolutely foolproof.
Listen, we all have to do our part in saving our environment and I want to make sure as many people as possible start generating their own power at home. Whether you want to reduce your electricity bill, eliminate it completely or even start getting paid for the extra electricity you generate, the Power4Home system is the solution you've been looking for.
Why Pay $1000's For Wind And Solar Power Systems When You Can Build Your Own Professional System For Less Than $200!
Home wind and solar power systems have been on the market for years. These systems work great, the only problem is that they'll cost you a few thousand dollars. This is the main reason this technology isn't in everyone's home.But that was just the beginning. After I began to tune the system to make it more energy-efficient, my typical utility bill was slashed by more than 80% (some months I even had a surplus of electricity, which not only gave me an electric bill of $0, it allowed me to sell my extra juice back to the power company—where they paid me instead!)
Well, at this point I realized that millions of people could benefit from what I had accomplished. But I had to figure out a way to build it inexpensively, using well-laid out plans that even non-techie's could read and use. Finally, I had to make sure it was safe and foolproof.
Perhaps even something that a father and son could build for themselves in a short weekend.
Well, it took some time, but eventually a friendlier more efficient version of the Power4Home System was born.
With it, I can help you slash your power bill by 80% or even eliminate it completely.
And remember the kicker: if you generate more energy than you use, the electricity company will pay you!
See, I've taken everything I've learned over the years and put together a kit that shows you exactly how to create electricity in your own backyard
Over 10 years ago, I quit my job as an electrician and dedicated my life to home power generation. I was fed up with waiting for the government and corporations to solve our energy crisis.
Slash Your Power Bills by 80% Or Even Eliminate Them Completely
I worked endlessly trying all sorts of equipment and technology, searching for an effective method to drastically reduce my power bill and finally become energy-independent.
When I finally developed a prototype, I wasn't sure what kind of an impact it would have on my electric bill. Especially when I realized that I would have to start running the energy-sucking air conditioner in the very first month of my test. I was shooting for a 50% drop in price, figuring I could always squeeze more out of it as I tweaked and perfected it further.
You can imagine my surprise when I slashed my bill by a jaw-dropping 74% in the very first month after plugging in the system.
Slash Your Power Bills by 80% Or Even Eliminate Them Completely
I worked endlessly trying all sorts of equipment and technology, searching for an effective method to drastically reduce my power bill and finally become energy-independent.
When I finally developed a prototype, I wasn't sure what kind of an impact it would have on my electric bill. Especially when I realized that I would have to start running the energy-sucking air conditioner in the very first month of my test. I was shooting for a 50% drop in price, figuring I could always squeeze more out of it as I tweaked and perfected it further.
You can imagine my surprise when I slashed my bill by a jaw-dropping 74% in the very first month after plugging in the system.
Build Your Own Wind Power System
Build Your Own Wind Power System
Wind power is a great backup for your solar panels on cloudy days and during the night. A few cheap items from your local hardware store and a couple of hours of construction can give you all the green energy you need from very your own windmill.
The instructions for building this energy producing windmill are very simple and anyone can build it using materials that cost less than $102.70.
Wind power is a great backup for your solar panels on cloudy days and during the night. A few cheap items from your local hardware store and a couple of hours of construction can give you all the green energy you need from very your own windmill.
The instructions for building this energy producing windmill are very simple and anyone can build it using materials that cost less than $102.70.
My Personal 100% Money-Back Customer Satisfaction Guarantee
My Personal 100% Money-Back Customer Satisfaction Guarantee
Listen, I want you to be as confident as I am and all the satisfied customers who've used the Power4Home system and are now saving tons of money. But just in case you have any lingering doubts whatsoever, I want to make it a no-brainer for you.
Get the guides and videos today. Read every word, download every bonus, watch every video, and should you need it, take me up on my free support. Build your own windmill or solar panel system in a weekend. See what a difference it makes in your home energy costs.
If you're not completely convinced that the Power4Home system is worth at least 100 times the investment, then I want you to ask for your money back. You've got a full 60 days to try it on me!
If you're not thrilled, I'm not. I'll cheerfully refund every penny you've paid, and we'll still part as friends.
Plus, you can still keep the entire Power4Home system, as well as all the bonus guides and videos for your trouble! It's my way of saying, "Thanks for giving my system a try."
The truth is, you NEVER have to worry about a refund. Why? Because once you actually start using this proven, step-by-step home energy technology you uncover in the Power4Home books, I'm confident you're going to hardly believe how much electricity you're saving.
John RusselCreator of the Power4Home System
We've spent years researching home energy systems
We've spent years researching home energy systems and know our system forward and backwards. As part of this special offer, you can send us any questions you may have on parts, installations, and any part of the Power4Home System.You can also tap our vast expertise to ensure you're saving as much on electricity as possible. We'll in turn spend as much time as is necessary to help you get the most out of the system.We already have plans in the works to charge a monthly fee for this service, because of the time and expense involved to make sure you get only the top professional support and care. But if you grab the Power4Home System today, you'll be locked in to get premium support for life!Value: $199 - Yours FREE!
Here's How To Start Saving The Planet And On Electricity Bills Now:
Simply click on the big blue "Order Now" button below and follow the easy instructions. As soon as you've placed your order, you'll get INSTANT ACCESS to the 3 main books, the videos, the bonus books and our special vendor parts list. All major credit cards and PayPal are accepted. Your purchase is protected by a 100% satisfaction money guarantee.
Here's How To Start Saving The Planet And On Electricity Bills Now:
Simply click on the big blue "Order Now" button below and follow the easy instructions. As soon as you've placed your order, you'll get INSTANT ACCESS to the 3 main books, the videos, the bonus books and our special vendor parts list. All major credit cards and PayPal are accepted. Your purchase is protected by a 100% satisfaction money guarantee.
Power4Home System for yourself right now!
You are about to get instant access to all the plans and instructions you need to create electricity in your own backyard.
The books are available in 9 different languages including English Spanish, Italian, Portuguese, French, Japanese, Chinese, Russian and German.
What To Do Next...
To start slashing your home energy costs immediately, claim the Power4Home System for yourself right now!
You'll get INSTANT ACCESS to all the guides, almost 3 hours of step-by-step videos, all the bonuses, checklists, and tax rebate forms, as well as our special vendor discounted parts list. All major credit cards and PayPal are accepted. Remember, your investment is protected by my bold 100% satisfaction money guarantee.
Sale Price Ending Soon - Get Yours Today!
Your Power4Home membership will allow you to reduce or even completely eliminate your electricity bill. All for a tiny onetime investment of $199.97 $49.97. Simply click here to get started at the limited time discounted investment.
The Power4Home guides are all 100% digitally downloadable immediately in Adobe PDF format which can be read and printed from your browser or any PDF reader.
The video series is in flash format, which you can watch in your browser directly through our video player with the click of a button. You get instant access to the entire system, day or night!
Easy Access to thePower4Home System
YES
YES, John! I want the electric company to pay me for a change! I want to slash my electric bills, squeeze more juice out of my home energy, and enjoy the benefits these step-by-step plans, methods, and resources will give me and my family!
Success Story
"I watched the power meter numbers turn backwards!"
Thanks so much for this user friendly how-to book. I was able to complete both projects in a week. And guess what? I actually had the thrill of standing there and watching the numbers on my power meter reverse and turn backwards! It was like hearing the sound of money being put back into the bank! How glorious!Frank Purna - Portland, OR
I want to live completely guilt free, laughing at rising electricity prices while rescuing the environment and saving tons of money in the process!
I want to learn the secrets to building my own solar panel and wind generator for less than $200 and slash my electricity bills by 80% or more. (Commercial systems can cost $10,000 or more!)
I know that if I don't get the results I want for any reason whatsoever within the first 60 days, I can ask for a complete refund with your bold 100% Customer Satisfaction Guarantee, and you will cheerfully refund my entire purchase price. Either way, I can't lose!
The books are available in 9 different languages including English Spanish, Italian, Portuguese, French, Japanese, Chinese, Russian and German.
What To Do Next...
To start slashing your home energy costs immediately, claim the Power4Home System for yourself right now!
You'll get INSTANT ACCESS to all the guides, almost 3 hours of step-by-step videos, all the bonuses, checklists, and tax rebate forms, as well as our special vendor discounted parts list. All major credit cards and PayPal are accepted. Remember, your investment is protected by my bold 100% satisfaction money guarantee.
Sale Price Ending Soon - Get Yours Today!
Your Power4Home membership will allow you to reduce or even completely eliminate your electricity bill. All for a tiny onetime investment of $199.97 $49.97. Simply click here to get started at the limited time discounted investment.
The Power4Home guides are all 100% digitally downloadable immediately in Adobe PDF format which can be read and printed from your browser or any PDF reader.
The video series is in flash format, which you can watch in your browser directly through our video player with the click of a button. You get instant access to the entire system, day or night!
Easy Access to thePower4Home System
YES
YES, John! I want the electric company to pay me for a change! I want to slash my electric bills, squeeze more juice out of my home energy, and enjoy the benefits these step-by-step plans, methods, and resources will give me and my family!
Success Story
"I watched the power meter numbers turn backwards!"
Thanks so much for this user friendly how-to book. I was able to complete both projects in a week. And guess what? I actually had the thrill of standing there and watching the numbers on my power meter reverse and turn backwards! It was like hearing the sound of money being put back into the bank! How glorious!Frank Purna - Portland, OR
I want to live completely guilt free, laughing at rising electricity prices while rescuing the environment and saving tons of money in the process!
I want to learn the secrets to building my own solar panel and wind generator for less than $200 and slash my electricity bills by 80% or more. (Commercial systems can cost $10,000 or more!)
I know that if I don't get the results I want for any reason whatsoever within the first 60 days, I can ask for a complete refund with your bold 100% Customer Satisfaction Guarantee, and you will cheerfully refund my entire purchase price. Either way, I can't lose!
You Will SEE The Difference Power4Home Makes On Your Utility Bills Or You Pay NOTHING
You Will SEE The Difference Power4Home Makes On Your Utility Bills Or You Pay NOTHING!
Just claim your copy of the Power4Home System and you'll get instant access to everything in the system, as well as your FREE gifts.
You must see dramatic results and be completely convinced the Power4Home System is worth at least 10 times your investment. Otherwise, I'll promptly refund 100% of what you paid.
And get this: Even in the extremely unlikely event you decide to exercise your right to a refund, the entire package you've received:
How To Easily Build Your Own Super-Efficient Solar Panels
How To Install The Power4Home System & Save $1000's
How To Build A High-Power Wind Generator
The 3 hours of step-by-step videos
...PLUS, the FREE bonuses:
The Exclusive Parts Suppliers List
83 Ways To Reduce Your Home Energy Needs
Advanced Power Saving Technology
The IRS TAX Rebate Forms
...Are yours to keep without further obligation—FREE!
Listen to your conscience..(And your wallet)
On this webpage, I've shown you how alternative sources of clean "green" energy are affordable, proven to work, and easier than you thought possible to build and install yourself for pennies on the dollar...
I've cited scores of examples showing you how big energy conglomerates are arranging sweetheart deals with our elected officials to maintain the status quo... to keep their OBSCENE profits sky-high, while members of Congress are funded lavishly...
I've shown you my own energy savings bill, and how you can get the power companies to pay you for your surplus electricity...
And I've painted a brighter environmental picture for our children and future generations—provided we act now, before it's too late to turn the tide.
Imagine yourself 8 weeks from now. Are you still paying high electricity prices and worrying about what your home is doing to the environment?
Or...
Are you living completely guilt free, laughing at rising electricity prices while rescuing the environment and saving tons of money?
Don't be forced to settle for more of the same utility rate increases your friends and neighbors are getting. Instead, why not be the one to lead the way and show them—and your own family—a better and brighter future.
If you're interested in learning how to install wind and solar power in your home for less than $200, you owe it to yourself to at least give the Power4Home System a try.
Sincerely,
John RusselElectrician, Researcher, Inventor, Home Energy Consultant, andCreator of the Power4Home System
P.S. The Power4Home System is the leading guide for homemade renewable energy. You can either get it now at this low introductory investment, or you can wait until the price increases after the initial offer expires shortly. You've got nothing to lose, because I'm assuming all the risk.
P.P.S. Join the thousands of other homes now making their own electricity. If you're not convinced the Power4Home System will reduce or eliminate your electric bill, I'll refund your entire investment, and we'll still part as friends. And you still get to keep everything for your trouble. What can be fairer than that? Try it now!
Just claim your copy of the Power4Home System and you'll get instant access to everything in the system, as well as your FREE gifts.
You must see dramatic results and be completely convinced the Power4Home System is worth at least 10 times your investment. Otherwise, I'll promptly refund 100% of what you paid.
And get this: Even in the extremely unlikely event you decide to exercise your right to a refund, the entire package you've received:
How To Easily Build Your Own Super-Efficient Solar Panels
How To Install The Power4Home System & Save $1000's
How To Build A High-Power Wind Generator
The 3 hours of step-by-step videos
...PLUS, the FREE bonuses:
The Exclusive Parts Suppliers List
83 Ways To Reduce Your Home Energy Needs
Advanced Power Saving Technology
The IRS TAX Rebate Forms
...Are yours to keep without further obligation—FREE!
Listen to your conscience..(And your wallet)
On this webpage, I've shown you how alternative sources of clean "green" energy are affordable, proven to work, and easier than you thought possible to build and install yourself for pennies on the dollar...
I've cited scores of examples showing you how big energy conglomerates are arranging sweetheart deals with our elected officials to maintain the status quo... to keep their OBSCENE profits sky-high, while members of Congress are funded lavishly...
I've shown you my own energy savings bill, and how you can get the power companies to pay you for your surplus electricity...
And I've painted a brighter environmental picture for our children and future generations—provided we act now, before it's too late to turn the tide.
Imagine yourself 8 weeks from now. Are you still paying high electricity prices and worrying about what your home is doing to the environment?
Or...
Are you living completely guilt free, laughing at rising electricity prices while rescuing the environment and saving tons of money?
Don't be forced to settle for more of the same utility rate increases your friends and neighbors are getting. Instead, why not be the one to lead the way and show them—and your own family—a better and brighter future.
If you're interested in learning how to install wind and solar power in your home for less than $200, you owe it to yourself to at least give the Power4Home System a try.
Sincerely,
John RusselElectrician, Researcher, Inventor, Home Energy Consultant, andCreator of the Power4Home System
P.S. The Power4Home System is the leading guide for homemade renewable energy. You can either get it now at this low introductory investment, or you can wait until the price increases after the initial offer expires shortly. You've got nothing to lose, because I'm assuming all the risk.
P.P.S. Join the thousands of other homes now making their own electricity. If you're not convinced the Power4Home System will reduce or eliminate your electric bill, I'll refund your entire investment, and we'll still part as friends. And you still get to keep everything for your trouble. What can be fairer than that? Try it now!
Aldous, S. How Solar Cells Work. Retrieved October, 2008, from
Aldous, S. How Solar Cells Work. Retrieved October, 2008, from http://www.howstuffworks.com/solar-cell.htm
Ben Arnoldy. (2008). Brighter Future for Solar Panels: Silicon Shortage Eases. Retrieved 1/22, 2009, from http://features.csmonitor.com/innovation/2008/06/05/brighter-future-for-solar-panels-silicon-shortage-eases/
CalFinder. What is net metering? Retrieved September, 2008, from http://solar.calfinder.com/blog/solar-information/what-is-net-metering/
Charlie White. (2008). Solar Cell Efficiency Reaches Breakthrough Cost per Watt. Retrieved 1/14, 2009, from http://dvice.com/archives/2008/03/solar_cell_effi.php
Code of Massachusetts Regulations. Massachusetts Net Metering Laws. http://www.dsireusa.org/documents/Incentives/MA01R.htm
Commonwealth Solar. Non-residential Rebate Calculator. http://www.masstech.org/SOLAR/Attachment%20A2-Non%20Residential%20Solar%20Rebate%20Calculator%20Only-070208.xls.
Commonwealth Solar. Overview. Retrieved September, 2008, from http://www.masstech.org/SOLAR/
Commonwealth Solar. (2008). Solar Photovoltaic Rebates: Program Manual. Retrieved September, 2008, from http://www.masstech.org/SOLAR/Commonwealth%20Solar%20Program%20Handbook_v2_070108.pdf
Cooler Planet. (2008). How Photovoltaic Cells Work. Retrieved October, 2008, from http://solar.coolerplanet.com/Content/Photovoltaic.aspx
Denis Lenardic. (2009). Photovoltaic Applications and Technologies. Retrieved 10/20, 2008, from www.pvresources.com
DSIRE. Massachusetts Incentives for Renewable Energy: Net Metering. Retrieved November, 2008, from http://www.dsireusa.org/library/includes/incentive2.cfm?Incentive_Code=MA01R&State=MA&CurrentPageID=1
DSIRE. Massachusetts Incentives for Renewable Energy. Retrieved November, 2008, from http://www.dsireusa.org/documents/Incentives/MA01R.htm
Energy Information Administration. (2009). Average Retail Prices of Electricity. http://www.eia.doe.gov/emeu/mer/prices.html
Evergreen Solar, Inc. (2008). Our String Ribbon Wafers - Genius in its Simplicity. Retrieved October, 2008, from http://www.evergreensolar.com/app/en/technology/item/48
Evergreen Solar, Inc. (2008). String Ribbon. Retrieved October, 2008, from http://evergreensolar.com/images/techology/stringribbon/diagram_string_ribbon_en.jpg Foley, B., Forbes, T., Jensen, H., & Young, A. (2006). Holy Name High School Wind Turbine Feasibility Study. WPI Interlibrary Database: Worcester Polytechnic Institute.
Global Footprint Network. (2008). Carbon Footprint. Retrieved 1/20, 2009, from http://www.footprintnetwork.org/en/index.php/GFN/page/carbon_footprint/
Harper Collins Publishers. (2009). The Green Bible. Retrieved 3/1, 2009 from http://greenletterbible.com/
Heliotronics. Heliotronics Data Acquisition Systems. http://www.heliotronics.com
John Markoff. (2007). The New York Times. Retrieved 1/23, 2008, from http://www.nytimes.com/2007/12/18/technology/18solar.html?ex=1355634000&en=091b06819623f9d0&ei=5088&partner=rssnyt&emc=rss
Lenardic, D. Solar Radiation Estimation and Site Analysis. Retrieved October 15, 2008, from http://www.pvresources.com/en/location.php
Lund, H., Nilson, R., Solamatova, D. & Skare, E. The History Highlight of Solar Cells. Retrieved October, 2008, from http://org.ntnu.no/solarcells/pages/history.php
Massachusetts Technology Collaborative. Commonwealth Solar Rebate Program. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS_AttachmentDMinimumTechnicalRequirements_v3_010109.pdf
Massachusetts Technology Collaborative. Information on Installers and Costs. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS%20Installer-Cost-Location%20Data%20for%20Website%20as%20of%2001-31-09.xls
Matti Tukiainen. GAISMA. Retrieved 10/5, 2008, from www.gaisma.com
National Renewable Energy Laboratory. U.S. Solar Radiation Resource Maps. Retrieved 9/25, 2008, from http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/
PowerFilm, Inc. (2008). Thin Film. Retrieved October, 2008, from http://www.powerfilmsolar.com/technology/index.html Quitana, M. A., King, D. L., & McMahon, T.J. and Osterwald, C.R. Commonly Observed Degradation in Field-Aged Photovoltaic Modules No. 2008)
Radiochemistry Society. Periodic table of Elements: Silicon. Retrieved October, 2008, from http://www.radiochemistry.org/periodictable/elements/14.html
REUK. Renewable Energy UK. Retrieved October, 2008, from http://www.reuk.co.uk/OtherImages/pnjunction.jpg Sands, E., Moussa, O., Meagher, G., & Lemaire, J. (2004). Solar Energy at Janssen Ortho LLC. WPI Interlibrary Database: Worcester Polytechnic Institute.
The Sietch Blog. Retrieved October, 2008, from www.blog.thesietch.org/wp-content/uploads/2007/06/solarcell.jpg Skinner, R., Moore, L., & Malczynski, L. (2002). A Rural Electric Co-op’s Experience with Photovoltaic Systems for Livestock Water Pumping
Solarbuzz. Photovoltaic industry statistics: Costs. Retrieved 1/10, 2009, from http://www.solarbuzz.com/statsCosts.htm
SolarHome.org. (2008). String-ribbon. Retrieved October, 2008, from http://www.solarhome.org/string-ribbon.html
The Solarserver. (2008). Photovoltaics. Retrieved October, 2008, from http://www.solarserver.de/wissen/photovoltaik-e.html
Tukiainen, M. (2009). Gaisma Retrieved October 15, 2008, from http://www.gaisma.com/en/location/worcester-massachusetts.html
U.S. Department of Energy. (2006). Polycrystalline Thin Film. Retrieved October, 2008, from http://www1.eere.energy.gov/solar/tf_polycrystalline.html Wailgum, J., Ledue, J., Chapman, J., & Al-Beik, H. (2003). Feasibility Study of a Solar Learning Lab at WPI. WPI Interlibrary Database: Worcester Polytechnic Institute. Woods, D. W. ISD Module: Quantitative Method in Economics. Wuashning, V. (2005). Understanding Renewable Energy Sources. London: Earthscan.
Ben Arnoldy. (2008). Brighter Future for Solar Panels: Silicon Shortage Eases. Retrieved 1/22, 2009, from http://features.csmonitor.com/innovation/2008/06/05/brighter-future-for-solar-panels-silicon-shortage-eases/
CalFinder. What is net metering? Retrieved September, 2008, from http://solar.calfinder.com/blog/solar-information/what-is-net-metering/
Charlie White. (2008). Solar Cell Efficiency Reaches Breakthrough Cost per Watt. Retrieved 1/14, 2009, from http://dvice.com/archives/2008/03/solar_cell_effi.php
Code of Massachusetts Regulations. Massachusetts Net Metering Laws. http://www.dsireusa.org/documents/Incentives/MA01R.htm
Commonwealth Solar. Non-residential Rebate Calculator. http://www.masstech.org/SOLAR/Attachment%20A2-Non%20Residential%20Solar%20Rebate%20Calculator%20Only-070208.xls.
Commonwealth Solar. Overview. Retrieved September, 2008, from http://www.masstech.org/SOLAR/
Commonwealth Solar. (2008). Solar Photovoltaic Rebates: Program Manual. Retrieved September, 2008, from http://www.masstech.org/SOLAR/Commonwealth%20Solar%20Program%20Handbook_v2_070108.pdf
Cooler Planet. (2008). How Photovoltaic Cells Work. Retrieved October, 2008, from http://solar.coolerplanet.com/Content/Photovoltaic.aspx
Denis Lenardic. (2009). Photovoltaic Applications and Technologies. Retrieved 10/20, 2008, from www.pvresources.com
DSIRE. Massachusetts Incentives for Renewable Energy: Net Metering. Retrieved November, 2008, from http://www.dsireusa.org/library/includes/incentive2.cfm?Incentive_Code=MA01R&State=MA&CurrentPageID=1
DSIRE. Massachusetts Incentives for Renewable Energy. Retrieved November, 2008, from http://www.dsireusa.org/documents/Incentives/MA01R.htm
Energy Information Administration. (2009). Average Retail Prices of Electricity. http://www.eia.doe.gov/emeu/mer/prices.html
Evergreen Solar, Inc. (2008). Our String Ribbon Wafers - Genius in its Simplicity. Retrieved October, 2008, from http://www.evergreensolar.com/app/en/technology/item/48
Evergreen Solar, Inc. (2008). String Ribbon. Retrieved October, 2008, from http://evergreensolar.com/images/techology/stringribbon/diagram_string_ribbon_en.jpg Foley, B., Forbes, T., Jensen, H., & Young, A. (2006). Holy Name High School Wind Turbine Feasibility Study. WPI Interlibrary Database: Worcester Polytechnic Institute.
Global Footprint Network. (2008). Carbon Footprint. Retrieved 1/20, 2009, from http://www.footprintnetwork.org/en/index.php/GFN/page/carbon_footprint/
Harper Collins Publishers. (2009). The Green Bible. Retrieved 3/1, 2009 from http://greenletterbible.com/
Heliotronics. Heliotronics Data Acquisition Systems. http://www.heliotronics.com
John Markoff. (2007). The New York Times. Retrieved 1/23, 2008, from http://www.nytimes.com/2007/12/18/technology/18solar.html?ex=1355634000&en=091b06819623f9d0&ei=5088&partner=rssnyt&emc=rss
Lenardic, D. Solar Radiation Estimation and Site Analysis. Retrieved October 15, 2008, from http://www.pvresources.com/en/location.php
Lund, H., Nilson, R., Solamatova, D. & Skare, E. The History Highlight of Solar Cells. Retrieved October, 2008, from http://org.ntnu.no/solarcells/pages/history.php
Massachusetts Technology Collaborative. Commonwealth Solar Rebate Program. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS_AttachmentDMinimumTechnicalRequirements_v3_010109.pdf
Massachusetts Technology Collaborative. Information on Installers and Costs. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS%20Installer-Cost-Location%20Data%20for%20Website%20as%20of%2001-31-09.xls
Matti Tukiainen. GAISMA. Retrieved 10/5, 2008, from www.gaisma.com
National Renewable Energy Laboratory. U.S. Solar Radiation Resource Maps. Retrieved 9/25, 2008, from http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/
PowerFilm, Inc. (2008). Thin Film. Retrieved October, 2008, from http://www.powerfilmsolar.com/technology/index.html Quitana, M. A., King, D. L., & McMahon, T.J. and Osterwald, C.R. Commonly Observed Degradation in Field-Aged Photovoltaic Modules No. 2008)
Radiochemistry Society. Periodic table of Elements: Silicon. Retrieved October, 2008, from http://www.radiochemistry.org/periodictable/elements/14.html
REUK. Renewable Energy UK. Retrieved October, 2008, from http://www.reuk.co.uk/OtherImages/pnjunction.jpg Sands, E., Moussa, O., Meagher, G., & Lemaire, J. (2004). Solar Energy at Janssen Ortho LLC. WPI Interlibrary Database: Worcester Polytechnic Institute.
The Sietch Blog. Retrieved October, 2008, from www.blog.thesietch.org/wp-content/uploads/2007/06/solarcell.jpg Skinner, R., Moore, L., & Malczynski, L. (2002). A Rural Electric Co-op’s Experience with Photovoltaic Systems for Livestock Water Pumping
Solarbuzz. Photovoltaic industry statistics: Costs. Retrieved 1/10, 2009, from http://www.solarbuzz.com/statsCosts.htm
SolarHome.org. (2008). String-ribbon. Retrieved October, 2008, from http://www.solarhome.org/string-ribbon.html
The Solarserver. (2008). Photovoltaics. Retrieved October, 2008, from http://www.solarserver.de/wissen/photovoltaik-e.html
Tukiainen, M. (2009). Gaisma Retrieved October 15, 2008, from http://www.gaisma.com/en/location/worcester-massachusetts.html
U.S. Department of Energy. (2006). Polycrystalline Thin Film. Retrieved October, 2008, from http://www1.eere.energy.gov/solar/tf_polycrystalline.html Wailgum, J., Ledue, J., Chapman, J., & Al-Beik, H. (2003). Feasibility Study of a Solar Learning Lab at WPI. WPI Interlibrary Database: Worcester Polytechnic Institute. Woods, D. W. ISD Module: Quantitative Method in Economics. Wuashning, V. (2005). Understanding Renewable Energy Sources. London: Earthscan.
increasing by 50% per annum, but that the supply will outpace it at 80% growth per year. “This
increasing by 50% per annum, but that the supply will outpace it at 80% growth per year. “This should be putting some downward pressure on prices,” he says.48 There are many companies working hard to bring down the cost of solar energy, and continue a trend that has gone on for a long time. Some of the first solar panels cost nearly $1800 per watt, while today people are striving to break the barrier of $1.00 per watt. Below is a graph showing the cost of solar panel installations in Japan since 1993.
48 http://features.csmonitor.com/innovation/2008/06/05/brighter-future-for-solar-panels-silicon-shortage-eases/ 49 http://www.solarbuzz.com/statsCosts.htm
Figure 27: Graph showing the falling cost of PV installations in Japan. 49 Though the graph is in Yen per Watt, the trend is a worldwide trend. The cost of solar panel systems is falling. Though it is difficult to predict exactly when solar panels will reach these predicted levels, one would expect that it will not be a long wait.
Appendix J: Scale Model
In order to create a better visual representation of the roof space and the shading throughout the day, a model was constructed. Along with this model was an arced piece of thin copper tubing with a light socket mounted to it. The base of the copper was hinged so that a combination of moving the arc up and down along with sliding the light from side to side approximated the sun at different times of day and the different times of the year. In a dark room, the 67-watt bulb provided enough light to get a good imitation of the shade. To further the experiment, a small solar cell was connected to a small LED and could be moved around to demonstrate how well light was absorbed at different locations on the roof. An added benefit of the model was its use in presentation to the church. By using the model as a presentation aid, potential panel locations the members of the church had a better idea of what would happen if they were to have the panels installed. See pictures of the model on the next page.
photo.jpg
photo1.jpg
PICT0951Appendix K: Site Pictures
PICT0947PICT0957
PICT0958
Appendix L: Simplified Economic Spreadsheet
In order for the church to re-evaluate investing in a photovoltaic system in the future, we created a simplified version of our economic spreadsheet using assumptions from our project. The three primary variables in this spreadsheet have been reduced to the overall cost per watt of the system, the proposed system size, and whether or not the solar panel components are manufactured in Massachusetts. The overall cost per watt would be given as a quote from an installer. If the solar panels are manufactured in Massachusetts, the rebate offered by Commonwealth Solar increases. The assumptions portion of the spreadsheet lists the various systems, economic, and rebate assumptions that were made in order to calculate the overall feasibility of the system. These assumptions can also be changed to see what different assumptions have on the overall feasibility. One factor of particular interest is the income generated by renewable energy credits. Because at the time of the report the future of such credits was uncertain, this number may change. The calculations section of the spreadsheet lists the raw system cost, the amount realized from the Commonwealth Solar rebate, the system cost after rebates are applied, the amount of energy the system would produce in a given year, how much savings this energy generation would translate to, and the number of years before this investment breaks even. The other pages of the spreadsheet are used as tools to help calculate the energy that the system would generate, and the value of the system as an investment. Below is a sample of the spreadsheet with $8.00 per watt and a system size of 20kW.
Solar Feasibility Analysis for the Wesley United Methodist Church
Entry Section:
Overall System Cost Per Watt:
$8.00
dollars / Watt
System Size:
20000
Watts
Solar Panels Manufactured in Massachusetts:
NO
YES / NO
Assumptions:
System Assumptions:
System Life Expectancy:
25
years
Yearly Performance Degradation:
0.50%
%
Efficiency of Solar Panels:
15.00%
%
DC to AC derating factor:
79.49%
%
Economic Assumptions:
REC Revenue per Watt:
$0.00
dollars
REC Annual Cost Adjuster:
4.00%
%
Yearly Energy Consumption:
102000
kWh
Cost of Electricity:
$0.16
dollars
Electricity Cost Inflation:
0.60%
%
Overall Inflation:
3.29%
%
MTC Assumptions:
System Size:
0 to 25 kW
25 to 100 kW
Base Incentive:
$3.25
$3.00
MA Component Adder:
$0.25
$0.25
Incremental Capacity:
20000
0
Calculations:
Raw System Cost:
$160,000.00
dollars
Rebate Amount:
$65,000.00
dollars
System Cost:
$95,000.00
dollars
Yearly Energy Generation:
27248
kWh
First Year Energy Production Value:
$4,359.68
dollars
Break Even Year:
22
years
Appendix M: Informational Brochure
To create a simple way to showcase the work we have done and our results, we created a brochure, which can be seen below:
Appendix N: Survey
Below is a listing of the questions that made up the survey given to our presentation audience: Do you believe that investing in renewable energy is important? If so, Why? What kind of image do you think a solar panel installation would give Wesley United Methodist Church? Would you install a solar panel system if there was no economic incentive to do so? In other words, if installing a solar panel system would have only have environmental benefits, would you still consider installing one? Do you know of any specific solar panel installations in the area, either residential or commercial? Do you think that a solar panel installation on the Wesley United Methodist Church is something that should be perused now, sometime in the future, or not at all? What do you feel was the overall quality of this presentation?
48 http://features.csmonitor.com/innovation/2008/06/05/brighter-future-for-solar-panels-silicon-shortage-eases/ 49 http://www.solarbuzz.com/statsCosts.htm
Figure 27: Graph showing the falling cost of PV installations in Japan. 49 Though the graph is in Yen per Watt, the trend is a worldwide trend. The cost of solar panel systems is falling. Though it is difficult to predict exactly when solar panels will reach these predicted levels, one would expect that it will not be a long wait.
Appendix J: Scale Model
In order to create a better visual representation of the roof space and the shading throughout the day, a model was constructed. Along with this model was an arced piece of thin copper tubing with a light socket mounted to it. The base of the copper was hinged so that a combination of moving the arc up and down along with sliding the light from side to side approximated the sun at different times of day and the different times of the year. In a dark room, the 67-watt bulb provided enough light to get a good imitation of the shade. To further the experiment, a small solar cell was connected to a small LED and could be moved around to demonstrate how well light was absorbed at different locations on the roof. An added benefit of the model was its use in presentation to the church. By using the model as a presentation aid, potential panel locations the members of the church had a better idea of what would happen if they were to have the panels installed. See pictures of the model on the next page.
photo.jpg
photo1.jpg
PICT0951Appendix K: Site Pictures
PICT0947PICT0957
PICT0958
Appendix L: Simplified Economic Spreadsheet
In order for the church to re-evaluate investing in a photovoltaic system in the future, we created a simplified version of our economic spreadsheet using assumptions from our project. The three primary variables in this spreadsheet have been reduced to the overall cost per watt of the system, the proposed system size, and whether or not the solar panel components are manufactured in Massachusetts. The overall cost per watt would be given as a quote from an installer. If the solar panels are manufactured in Massachusetts, the rebate offered by Commonwealth Solar increases. The assumptions portion of the spreadsheet lists the various systems, economic, and rebate assumptions that were made in order to calculate the overall feasibility of the system. These assumptions can also be changed to see what different assumptions have on the overall feasibility. One factor of particular interest is the income generated by renewable energy credits. Because at the time of the report the future of such credits was uncertain, this number may change. The calculations section of the spreadsheet lists the raw system cost, the amount realized from the Commonwealth Solar rebate, the system cost after rebates are applied, the amount of energy the system would produce in a given year, how much savings this energy generation would translate to, and the number of years before this investment breaks even. The other pages of the spreadsheet are used as tools to help calculate the energy that the system would generate, and the value of the system as an investment. Below is a sample of the spreadsheet with $8.00 per watt and a system size of 20kW.
Solar Feasibility Analysis for the Wesley United Methodist Church
Entry Section:
Overall System Cost Per Watt:
$8.00
dollars / Watt
System Size:
20000
Watts
Solar Panels Manufactured in Massachusetts:
NO
YES / NO
Assumptions:
System Assumptions:
System Life Expectancy:
25
years
Yearly Performance Degradation:
0.50%
%
Efficiency of Solar Panels:
15.00%
%
DC to AC derating factor:
79.49%
%
Economic Assumptions:
REC Revenue per Watt:
$0.00
dollars
REC Annual Cost Adjuster:
4.00%
%
Yearly Energy Consumption:
102000
kWh
Cost of Electricity:
$0.16
dollars
Electricity Cost Inflation:
0.60%
%
Overall Inflation:
3.29%
%
MTC Assumptions:
System Size:
0 to 25 kW
25 to 100 kW
Base Incentive:
$3.25
$3.00
MA Component Adder:
$0.25
$0.25
Incremental Capacity:
20000
0
Calculations:
Raw System Cost:
$160,000.00
dollars
Rebate Amount:
$65,000.00
dollars
System Cost:
$95,000.00
dollars
Yearly Energy Generation:
27248
kWh
First Year Energy Production Value:
$4,359.68
dollars
Break Even Year:
22
years
Appendix M: Informational Brochure
To create a simple way to showcase the work we have done and our results, we created a brochure, which can be seen below:
Appendix N: Survey
Below is a listing of the questions that made up the survey given to our presentation audience: Do you believe that investing in renewable energy is important? If so, Why? What kind of image do you think a solar panel installation would give Wesley United Methodist Church? Would you install a solar panel system if there was no economic incentive to do so? In other words, if installing a solar panel system would have only have environmental benefits, would you still consider installing one? Do you know of any specific solar panel installations in the area, either residential or commercial? Do you think that a solar panel installation on the Wesley United Methodist Church is something that should be perused now, sometime in the future, or not at all? What do you feel was the overall quality of this presentation?
Along with this letter, the church should request a cost breakdown. This should detail what
Along with this letter, the church should request a cost breakdown. This should detail what portion of the cost is for labor, panels, mounting equipment, etc. Having costs broken down in this way will help determine which installer is the best choice and it helps clarify their overall cost. Step four is to receive the quotes from the contractors. Generally speaking, any quotes received after the given deadline should be disregarded. If the contractor doesn’t meet the requested deadline for the quote, then they probably can’t be counted on to be reliable when it comes to the installation. Simply put, a company that can’t meet the deadline for a quote is probably not professional enough for a system of this size. The fifth step is to begin the down selecting process. In this part, the church needs to generate several factors that are the most important to them. Generally, cost is one of these. Other important factors to consider are the type and quality of the panels and mounting hardware, expected completion date, or use of local labor. Once the church establishes their important criteria, they can begin to rank the different installers. It is important to keep in mind the two factors of cost and quality of materials and find the best compromise between the two. The sixth and final step is to send letters to all the contractors who submitted quotes. Inform the one the church chose and clarify a payment schedule. It’s also important to inform the contractors that didn’t win and inform them as to why they were not selected. These are the steps involved in requesting a bit from a contractor and are designed to streamline the process for both the contractor and the customer. Following these steps should put the church in the best position to select the installer that they determine to have the greatest value.
Appendix C: Site Dimensions
Appendix D: Morning Shade
Appendix E: Afternoon Shade
Appendix F: Shading with Raised Panels
Appendix G: Meetings and Correspondence
Meeting with Tom Sikina on December 5, 2008:
After introducing ourselves and our project, the first topic of discussion was regarding irradiation data. Mr. Sikina made the point that different sites and organizations that offer irradiation data may not take the same factors into account. For example, some sources do not consider cloud cover. The inclusion or exclusion of such factors in a model could have substantial impacts on a final result. Next, we discussed third party financing. Mr. Sikina told us to think of having a third party finance a solar panel system analogous buying a bond. The third party would own the system for a given period of time (25 years, for example) and the buyer would get electricity at a discounted rate. After the contract is over, the buyer usually has the option to buy the solar panel system from the third party for a small price. Another issue that was brought up was the level of confidence in our model. This level of confidence refers to how sure we are that our model would be an accurate predictor of feasibility. Mr. Sikina urged us to compare our model to similar projects that have been found to be feasible, and run them through our model. After showing Mr. Sikina our economic model, he had a number of comments. One was that we pay particular consideration to the percentage increase in electricity costs per year. Overall, he said that our current estimates were fairly conservative.
The next topic of discussion concerned the accuracy of the ratings that solar panel companies give their panels. On Mr. Sikina’s installation, the solar panels only operate at 85% of the rating on their data sheet. However, Mr. Sinkina knows of another installation using a different brand of panels that operate at 5% over their specifications. It was suggested that the accuracy of solar panel production
data should verified before making a final choice. Furthermore, Mr. Sikina suggested that WPI may be able to act as a third party that rates solar panels against their factory specifications. On the topic of installing solar panels, we discussed the feasibility of changing the angle of solar panels throughout the year to produce more energy. One of the simplest and most effective methods would be a two-pin system, where the panels can be locked into one of two different tilts. At different time during the year, the tilts could be manually adjusted. Mr. Sikina encouraged that we calculate the net energy change from employing such a system. Expanding on the topic of installation and optimum panel placement, we discussed the idea of creating a small scale model to test different panel placements and orientations. A model may give insight to how spacing the panels affect net energy production as well as how shadows are cast in a more complex system. The final topic of the discussion was about the bid process for finding an installer. Mr. Sikina outlined the following steps:
1. Find the system you want to buy 2. Select the bidders 3. Write a bid proposal (RFQ letter) and send to bidders 4. Receive quotes 5. Prepare a justification of the bid (known as a down select) based on your lists of criteria 6. Award the winning bidder
Mr. Sikina suggested that since we may not be involved in the church’s actual installation process that we give the church a recommended bidding process to follow if they decide to go forward with installing a solar panel system.
Meeting with York-Ogunquit United Methodist Church
Research for similar case studies discovered that the York-Ogunquit United Methodist Church in York, Maine, installed a system of solar panels approximately 6 months before our project began. A meeting was set up with this church to find specific information, since both churches are in a similar region, less than 2 hours apart. The meeting began with explaining the project and the specific situation of the Wesley United Methodist Church to Rev. Shook. After detailing the project goals and the needs of the church, Rev. Shook began to share all the information he had available on the solar installation for the his church. On this particular day, it was snowing so taking pictures of the system was difficult. The system the church decided on is rated for 7,700 W, however the maximum output that has been achieved to date has peaked at 6000 W. The system consists of 42 panels that are mounted directly to the raised seams of the steel roof. The installation was completed by Solar Market of Arundel, Maine, in two days for a total system cost of $58,000. Of this overall cost, $11,220 was the cost of 2 days of installation. In this case, the installation cost is about 20% of the total, which led us to reevaluate our previous information stating that installation accounted for nearly half of the total cost. This system produces enough extra electricity in the summer months to provide the church with renewable energy credits with Central Maine Power. These credits cover about half of the winter electricity use. This means that the church only needs to pay for using electricity for about 4 months a year. The other bills are only to cover various other charges, and are usually around 25 dollars. In this way, the church is not only reducing its environmental impact, but it is saving a considerable amount of money in its monthly operating expenses.
The money for the system came from a trust fund set up by the church after selling one of their two buildings several years ago. In addition, the proponents of the system held information sessions for about a year to help the congregation understand the options and benefits of the investment. By holding these sessions, most of the questions people had were answered; leaving very little opposition
by the time a decision was made. Rev. Shook said that the members of the church are glad to be better environmental stewards that set the example for their community just as much as they enjoy the economic benefits.
Correspondence with the Massachusetts Technology Collaborative:
In order to understand the nature and stipulations of the rebate offered through Commonwealth Solar, we contacted a member of the Massachusetts Technology Collaborative (MTC), the parent organization of Commonwealth solar. Through email conversations, we learned two important factors in regards to the rebate:
1. The church was not considered a public building for the sake of the rebate. This meant it did not qualify for the extra $1.00 per watt entitled to public buildings. 2. Installation had to be done though an installer certified through Commonwealth Solar. This meant that a volunteer installation could not be done without a special agreement through the installer chosen to do the installation.
Correspondence with solar panel installers:
In order to get an estimate of cost breakdowns for the overall price per watt figure given by solar panel installers, we sent an email to seven major installers in the area asking them for estimates. Of the seven companies asked, three responded, and the results can be seen below: Company 1: Solar Panel Components: 75% Mounting Materials 10% Installation Labor Costs 15% Company 2:
Solar panels: 55% Inverter, electrical wiring, disconnects: 15% Mounting hardware: 15%
Installation: 13% Permits: 2% Company 3: Solar Modules: 60% Racking and Inverters: 20% Labor: 20%
Appendix H: Solar panel installers
Below is a list of recommended solar panel installers. These installers have been chosen on their overall system cost per watt, the size of the systems they have previously installed, and recommendations from our sources. New England Breeze, LLC President: Mark Durrenberger Phone: 978-212-2665
Email: Info@NewEnglandBreeze.com
Web: www.newenglandbreeze.com Solar Works, Inc. Regional Project Director: Terry Dupuis, P.E. Phone: 508-360-4907
Email: tdupuid@solarworksinc.com
Web: www.solarwaorksinc.com Berkshire Photovoltaic Services Phone: 413-743-0152
Email: info@bpvs.com
Web: http://www.bpvs.com/ Borrego Solar Systems, Inc. Phone: 978-513-2600
Web: www.borregosolar.com/ Nexamp, Inc. Phone: 978-688-2700
Email: info@nexamp.com
Web: www.nexamp.com SolarFlair, Inc. Phone: 508-293-4293
Email: info@solarflair.com
Web: www.solarflair.com SolarWrights, Inc. Phone: 401-396-9901
Email: info@solarwrights.com
Web: www.solarwrights.com/
Appendix I: Future Solar Panel Costs
It is the widely held expectation that solar panel costs will continue to fall over the coming years, naturally increasing the likelihood that solar panel projects will become feasible. Many cite economics of scale and the experience of other industries: as the demand rises and the supply increases to meet it, larger, more efficient factories are set up. It is difficult to predict with much accuracy what the cost of solar panels will be in the future, but many companies and researchers in field of solar panel pricing expect that the price of solar panels will come down.
Nanosolar, a startup company that has opened a manufacturing facility in Silicon Valley, is claiming that they have found a way to reduce the cost of solar panel production by 80% by “printing” thin film solar panels onto Aluminum and saving significant amounts of silicon. Martin Roscheisen, CEO of Nanosolar, says that they will be the first company to profitably sell solar panels for under $1.00 per watt, and that “with a $1-per-watt panel, it is possible to build $2-per-watt systems.”46 These are certainly bold, and if they prove to be true, would make solar panel systems instantly feasible. The company has orders for their first 18 months of production.
46 http://www.nytimes.com/2007/12/18/technology/18solar.html?ex=1355634000&en=091b06819623f9d0&ei=5088&partner=rssnyt&emc=rss 47 http://dvice.com/archives/2008/03/solar_cell_effi.php
Another small company, 1366 Technologies from Massachusetts, says they have found a breakthrough technology that makes there solar panels 27% more efficient. This will allow them to start selling solar panels soon for $1.30 per watt, and they expect that by 2012 they will also be selling solar panels for $1.00 per watt.47
In a study done by Travis Bradford, president of the Prometheus Institute for Sustainable Development in Cambridge, MA, even with the traditional production methods, solar panel costs could fall by as much as 1/3rd over the next couple years. His research shows that solar panel demand is
Appendix C: Site Dimensions
Appendix D: Morning Shade
Appendix E: Afternoon Shade
Appendix F: Shading with Raised Panels
Appendix G: Meetings and Correspondence
Meeting with Tom Sikina on December 5, 2008:
After introducing ourselves and our project, the first topic of discussion was regarding irradiation data. Mr. Sikina made the point that different sites and organizations that offer irradiation data may not take the same factors into account. For example, some sources do not consider cloud cover. The inclusion or exclusion of such factors in a model could have substantial impacts on a final result. Next, we discussed third party financing. Mr. Sikina told us to think of having a third party finance a solar panel system analogous buying a bond. The third party would own the system for a given period of time (25 years, for example) and the buyer would get electricity at a discounted rate. After the contract is over, the buyer usually has the option to buy the solar panel system from the third party for a small price. Another issue that was brought up was the level of confidence in our model. This level of confidence refers to how sure we are that our model would be an accurate predictor of feasibility. Mr. Sikina urged us to compare our model to similar projects that have been found to be feasible, and run them through our model. After showing Mr. Sikina our economic model, he had a number of comments. One was that we pay particular consideration to the percentage increase in electricity costs per year. Overall, he said that our current estimates were fairly conservative.
The next topic of discussion concerned the accuracy of the ratings that solar panel companies give their panels. On Mr. Sikina’s installation, the solar panels only operate at 85% of the rating on their data sheet. However, Mr. Sinkina knows of another installation using a different brand of panels that operate at 5% over their specifications. It was suggested that the accuracy of solar panel production
data should verified before making a final choice. Furthermore, Mr. Sikina suggested that WPI may be able to act as a third party that rates solar panels against their factory specifications. On the topic of installing solar panels, we discussed the feasibility of changing the angle of solar panels throughout the year to produce more energy. One of the simplest and most effective methods would be a two-pin system, where the panels can be locked into one of two different tilts. At different time during the year, the tilts could be manually adjusted. Mr. Sikina encouraged that we calculate the net energy change from employing such a system. Expanding on the topic of installation and optimum panel placement, we discussed the idea of creating a small scale model to test different panel placements and orientations. A model may give insight to how spacing the panels affect net energy production as well as how shadows are cast in a more complex system. The final topic of the discussion was about the bid process for finding an installer. Mr. Sikina outlined the following steps:
1. Find the system you want to buy 2. Select the bidders 3. Write a bid proposal (RFQ letter) and send to bidders 4. Receive quotes 5. Prepare a justification of the bid (known as a down select) based on your lists of criteria 6. Award the winning bidder
Mr. Sikina suggested that since we may not be involved in the church’s actual installation process that we give the church a recommended bidding process to follow if they decide to go forward with installing a solar panel system.
Meeting with York-Ogunquit United Methodist Church
Research for similar case studies discovered that the York-Ogunquit United Methodist Church in York, Maine, installed a system of solar panels approximately 6 months before our project began. A meeting was set up with this church to find specific information, since both churches are in a similar region, less than 2 hours apart. The meeting began with explaining the project and the specific situation of the Wesley United Methodist Church to Rev. Shook. After detailing the project goals and the needs of the church, Rev. Shook began to share all the information he had available on the solar installation for the his church. On this particular day, it was snowing so taking pictures of the system was difficult. The system the church decided on is rated for 7,700 W, however the maximum output that has been achieved to date has peaked at 6000 W. The system consists of 42 panels that are mounted directly to the raised seams of the steel roof. The installation was completed by Solar Market of Arundel, Maine, in two days for a total system cost of $58,000. Of this overall cost, $11,220 was the cost of 2 days of installation. In this case, the installation cost is about 20% of the total, which led us to reevaluate our previous information stating that installation accounted for nearly half of the total cost. This system produces enough extra electricity in the summer months to provide the church with renewable energy credits with Central Maine Power. These credits cover about half of the winter electricity use. This means that the church only needs to pay for using electricity for about 4 months a year. The other bills are only to cover various other charges, and are usually around 25 dollars. In this way, the church is not only reducing its environmental impact, but it is saving a considerable amount of money in its monthly operating expenses.
The money for the system came from a trust fund set up by the church after selling one of their two buildings several years ago. In addition, the proponents of the system held information sessions for about a year to help the congregation understand the options and benefits of the investment. By holding these sessions, most of the questions people had were answered; leaving very little opposition
by the time a decision was made. Rev. Shook said that the members of the church are glad to be better environmental stewards that set the example for their community just as much as they enjoy the economic benefits.
Correspondence with the Massachusetts Technology Collaborative:
In order to understand the nature and stipulations of the rebate offered through Commonwealth Solar, we contacted a member of the Massachusetts Technology Collaborative (MTC), the parent organization of Commonwealth solar. Through email conversations, we learned two important factors in regards to the rebate:
1. The church was not considered a public building for the sake of the rebate. This meant it did not qualify for the extra $1.00 per watt entitled to public buildings. 2. Installation had to be done though an installer certified through Commonwealth Solar. This meant that a volunteer installation could not be done without a special agreement through the installer chosen to do the installation.
Correspondence with solar panel installers:
In order to get an estimate of cost breakdowns for the overall price per watt figure given by solar panel installers, we sent an email to seven major installers in the area asking them for estimates. Of the seven companies asked, three responded, and the results can be seen below: Company 1: Solar Panel Components: 75% Mounting Materials 10% Installation Labor Costs 15% Company 2:
Solar panels: 55% Inverter, electrical wiring, disconnects: 15% Mounting hardware: 15%
Installation: 13% Permits: 2% Company 3: Solar Modules: 60% Racking and Inverters: 20% Labor: 20%
Appendix H: Solar panel installers
Below is a list of recommended solar panel installers. These installers have been chosen on their overall system cost per watt, the size of the systems they have previously installed, and recommendations from our sources. New England Breeze, LLC President: Mark Durrenberger Phone: 978-212-2665
Email: Info@NewEnglandBreeze.com
Web: www.newenglandbreeze.com Solar Works, Inc. Regional Project Director: Terry Dupuis, P.E. Phone: 508-360-4907
Email: tdupuid@solarworksinc.com
Web: www.solarwaorksinc.com Berkshire Photovoltaic Services Phone: 413-743-0152
Email: info@bpvs.com
Web: http://www.bpvs.com/ Borrego Solar Systems, Inc. Phone: 978-513-2600
Web: www.borregosolar.com/ Nexamp, Inc. Phone: 978-688-2700
Email: info@nexamp.com
Web: www.nexamp.com SolarFlair, Inc. Phone: 508-293-4293
Email: info@solarflair.com
Web: www.solarflair.com SolarWrights, Inc. Phone: 401-396-9901
Email: info@solarwrights.com
Web: www.solarwrights.com/
Appendix I: Future Solar Panel Costs
It is the widely held expectation that solar panel costs will continue to fall over the coming years, naturally increasing the likelihood that solar panel projects will become feasible. Many cite economics of scale and the experience of other industries: as the demand rises and the supply increases to meet it, larger, more efficient factories are set up. It is difficult to predict with much accuracy what the cost of solar panels will be in the future, but many companies and researchers in field of solar panel pricing expect that the price of solar panels will come down.
Nanosolar, a startup company that has opened a manufacturing facility in Silicon Valley, is claiming that they have found a way to reduce the cost of solar panel production by 80% by “printing” thin film solar panels onto Aluminum and saving significant amounts of silicon. Martin Roscheisen, CEO of Nanosolar, says that they will be the first company to profitably sell solar panels for under $1.00 per watt, and that “with a $1-per-watt panel, it is possible to build $2-per-watt systems.”46 These are certainly bold, and if they prove to be true, would make solar panel systems instantly feasible. The company has orders for their first 18 months of production.
46 http://www.nytimes.com/2007/12/18/technology/18solar.html?ex=1355634000&en=091b06819623f9d0&ei=5088&partner=rssnyt&emc=rss 47 http://dvice.com/archives/2008/03/solar_cell_effi.php
Another small company, 1366 Technologies from Massachusetts, says they have found a breakthrough technology that makes there solar panels 27% more efficient. This will allow them to start selling solar panels soon for $1.30 per watt, and they expect that by 2012 they will also be selling solar panels for $1.00 per watt.47
In a study done by Travis Bradford, president of the Prometheus Institute for Sustainable Development in Cambridge, MA, even with the traditional production methods, solar panel costs could fall by as much as 1/3rd over the next couple years. His research shows that solar panel demand is
Figure 23: 25kW System Energy Production
Figure 23: 25kW System Energy Production The chart above depicts the energy consumed by The Wesley United Methodist Church, seen in blue, and the electricity produced by the 25kW solar array, seen in red. The total “net” usage is seen in green which is the difference between the energy consumed and the energy produced.
Figure 24: 25kW System Cash Flow with Volunteer Installation Figure 8 depicts the total cash flow of the 25kW array with volunteer installation. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7.6 Assessment:
Revisiting the scenarios above, cost of installation is the single most important factor in whether a system will be feasible. Currently, the cost-per-watt of solar panels is generally fixed at $4-$5. This allows minor room to reduce the cost. However, because installation is not necessarily a fixed cost and most of the work can be done by knowledgeable volunteers it is possible to keep this cost much lower.
Another noticeable result of analyzing these scenarios is that the systems of varying sizes all have a break-even point of approximately nineteen years. The main reason for this phenomenon is the fact that larger arrays, despite their greater initial investment, recover savings much quicker because of their greater electricity production. The 25kW array may generate $164,997.40 in the course of 25 years compared to a smaller, 10kW array which may only produce $65,998.96 of revenue. This observation
displays the fact that a larger solar array is much more beneficial in the long term; however a small one is financially easier in the short term.
7.7 Sensitivity Analysis
Although we have determined that a largest array is the optimal scenario for the production of electricity the nine-teen year break-even point is near the system life expectancy of 20-25 years. However the cost of solar cells is constantly decreasing. Based on discussions with solar manufacturers and installers, it is expected that costs for solar panels will fall quickly in the next three to five years and the payback period will thus decrease rapidly. To illustrate the effect influence lower costs on the solar market we decided to create a sensitivity analysis. This analysis below offers a fifth scenario that projects possible costs and efficiencies of solar panels in five years. The following is a scenario assumes that in the future, technology will reduce the cost-per-watt of a solar panel from $4.30 to $2.00 and increase the solar cell efficiency from 15% to 20%. The result is a dramatic drop in the amount of time it takes to break-even. The period of time necessary to break-even drops from nineteen years to only nine and the number of panels required to generate the same amount of electricity is reduced from 117 panels to 88. The reduction in the number of panels also reduces the need to install solar panels in sub-optimal locations.
Figure 25: Futuristic 25kW System Cash Flow Figure 9 depicts the total cash flow of a 25kW array purchased in five years. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
Figure 26: The Effect of Waiting 5 Years The chart above depicts the outcome if a 25kW system, scenario three, was purchased in the present time period and if a 25kW system was purchased in five years using the data described above. As the results in figure 10 clearly demonstrate, it would be much more beneficial, economically, to implement a 25kW system after five years rather than at the current time period.
8. Social and Environmental Impact
The significance of solar panel systems go far beyond financial factors. Alternative forms of energy are important to the sustainability of our planet. This section identifies the social and environmental impacts that a solar panel installation would have on the church and what we have done to disseminate information about solar panel installations.
8.1 Effects on Carbon Footprint
A Carbon footprint is a measurement of the impact a person or a building has on the environment. It is usually represented as the number of tons of carbon dioxide released into the atmosphere by things such as power plants, cars, or burning heating oil. Based on information available from the Global Footprint Network, current levels of emissions exceed the capacity that the earth is able to absorb. This rate has been sharply increasing since the 1960s.41 Finding solutions to the problem of increased emissions is critical to environmental sustainability. However, offsetting the world’s carbon emissions by planting trees isn’t an efficient solution to the problem of increased emissions. A better solution is reducing the emissions themselves. Reduction of emissions requires cutting back the use of fossil fuels. This means driving less, using cars that are more efficient, and meeting high standards for emissions testing. It also means using less electricity, and when possible looking for ‘green’ alternatives. Sources of environmentally friendly electricity include solar PV, wind energy, and hydroelectric; although hydroelectric plants significantly disrupt the river upon which they are built.
41 Global Footprint Network. Globalfootprintnetwork.com. [Online] [Cited: December 2, 2008.] http://www.footprintnetwork.org/en/index.php/GFN/page/carbon_footprint/.
The church’s carbon footprint is primarily made up of the electricity it consumes, and the natural gas used for heating. Based on the formulas used by the Global Footprint Network the annual
electricity consumption creates 59 tons of carbon dioxide.42 The total amount of carbon dioxide created by or on behalf of the church is at least 67 tons of CO2 emissions per year.2 If the church were to install a 25kW solar array, they would significantly reduce the their annual emissions to 39 tons of CO2, a thirty three percent reduction.
42 Global Footprint Network. Globalfootprintnetwork.com. [Online] http://www.carbonfootprint.com/carbonfootprint.html 43 Harper Collins Publishers. (2009). The Green Bible. Retrieved 3/1, 2009 from http://greenletterbible.com/
8.2 Environmental Stewardship
Wesley United Methodist Church commissioned this study of green technology as an expression of its commitment towards “environmental stewardship.” Many of the individuals who participate in the church feel that it is their responsibility to the community to contribute to the adoption of clean energy. For that reason, the implementation of a solar array would not only reduce green house emissions, but also spread awareness to the wider community and inspire other community members to follow suit. As stewards of the Earth, a church could send a powerful message to the community by acting on these values in their place of worship.
Green stewardship is rapidly becoming a popular topic in the Christian community. There is a new bible that has been printed called the “Green Bible”. It highlights eco-friendly passages in green and has an index in the back where one can look up “green” passages. It is said that the “Green Bible sets out an urgent agenda for the Christian community.”43 One particularly relevant passage from Leviticus is as follows, “You shall not strip your vineyard bare, or gather the fallen grapes of your vineyard; you shall leave them for the poor and the alien: I am the Lord your God”. Another moving passage in support of green stewardship is from Psalm 24, “The earth is the Lord’s and everything in it, the world, and all who live in it.”
Green stewardship is a movement within the church that is rapidly gaining momentum as more and more Christians become aware of the threat humans pose to the planet. As the earth’s destruction continues, many are starting to feel it is part of their calling as followers of God to help. The city of Worcester has many churches of many faiths each concerned about the cost of rising electricity as well as the benefits of helping the environment. If the Wesley United Methodist Church were to decide to implement a solar system, it would be recognized as one of the first churches in the area to do so and demonstrate its leadership as an environmental steward in the community. If the implementation of green energy proves to be beneficial the Wesley United Methodist Church will become an example to those in Worcester and New England.
8.3 Informational Brochure
An informational brochure has been created to spread information to the church about the benefits of solar panel installations. Our correspondence with a Methodist Church from Maine showed us that the spread of information about a solar panel project can greatly reduce opposition and build support for this costly expenditure. The brochure captures the essence of our results. It has financial information, including a graph about the amount of energy produced with a large scale system and a graph showing how the payback period is directly related to the system cost per watt. The brochure also includes a couple of passages from the bible that support the concept of green stewardship and accompanying pictures of God’s magnificent creation. The brochure can be found in Appendix M: Informational Brochure.
8.4 Survey
After our final presentation, given on March 1, 2009, we handed out a brief survey to those who were in attendance (Appendix N). The audience consisted primarily but not exclusively of members of the Board of Trustees and Finance Committee at Wesley. There were only fourteen people in
attendance, so the survey is of little statistical value; however it has helped us to realize some of the general perceptions held by the congregation. All fourteen people responded they felt that investment in alternative energy is important, however their reasons for this answer varied. Some cited green stewardship as their primary reason, while others pointed to the fact that there is a finite supply of fossil fuels. Still others felt that alternative energy was important so that the country could become independent of foreign oil. Most mentioned that it was important to be environmentally conscious and many responses included a combination of these reasons. In response to the second question, which asked about what the public’s perception of a solar panel installation on Wesley United Methodist Church would be, the answers were again unanimous. All responses stated that the public’s view of such an installation would be positive. One responder felt that it would have limited affect, and only be slightly positive, while many responded that this would be “very positive”, “forward thinking”, and “green.” The last two questions had a wider range of responses than the first two. When asked whether or not a solar panel installation should be pursued even if there was no economic gain, most said that it should be pursued for environmental reasons, however, there were a few responses that said that the only factor that was important to them was the financial savings.
Finally, on the last question, which asked whether or not Wesley United Methodist Church should pursue a solar installation now, in the future, or not at all, there was the widest disparity of answers. A number of people felt that the church should wait for five years and then reevaluate the situation, while others felt that church should do more research about it now. Some people felt that the church should absolutely pursue it now, while there was one response that said it should not be pursued at all.
While everyone in attendance of our final presentation felt that alternative energy was important, it can be seen by looking at the remainder of the questions that this belief was weighted differently by each person. Looking into the future, the congregation will have a lot to debate as they try to decide what to do with the results of this project.
9. Conclusions and Recommendations
The benefits of solar panel installations are numerous, ranging from green stewardship to reducing the church’s carbon footprint, and from building a strong public image for the church to reducing the church’s monthly electricity bills. The feasibility of such a system is not determined by a financial analysis alone. Based on current prices, a solar panel system installed at Wesley United Methodist church would have a nine-teen year payback period. We recommend that the church strongly weigh the positive impacts of solar panels alongside the economic feasibility of installation. With the present conditions, it is unlikely that a solar panel installation will lose money over the lifetime of the system; however, it requires a large capital investment and has a slow payback. The church should monitor future the economic conditions using the “Simplified Economics Spreadsheet for Wesley United Methodist Church” that we have provided to get an estimate of economic feasibility of a solar power system. When it is determined that the benefits from a solar panel installation outweigh its drawbacks, such as when the cost per watt drops below a threshold price, the church should follow the procedure outlined below:
1. Form a committee of people who are interested in seeing this project carried forward. 2. Have the committee hold meetings/focus groups with interested members of the congregation to educate the congregation about solar panels and answer any concerns. The committee can use our presentation, brochure, and any of the other materials in this report. 3. Have the committee members contact three to five installers and go through the bidding process as we have outlined.
4. Use the graph “Simplified Economics Spreadsheet for Wesley United Methodist Church” with current data to determine the financial feasibility of this system.
After estimates have been received, the selection process can begin. After choosing an installer, the rest of the process, such as acquiring the Commonwealth Solar rebate and fulfilling permit obligations will be handed by the chosen installer. Hopefully, as solar panel technology continues to drop in price, the church will be able to reap the benefits of clean, renewable energy.
Appendix A: Solar Panel Tilt Analysis
Analysis of the installation orientation of solar panels is crucial to getting the highest power output from the solar panels. Solar panels receive the most energy from the sun when the surface of the solar panel is perpendicular to the sun’s rays. Some solar panels track the position of the sun. The surface of these panels is always perpendicular to the sun, giving tracking panels the highest output of any mounting system. However, the increase in efficiency does not come without a cost. Tracking mounting systems are significantly more expensive than other mounting options and are also a lot more likely to break.
In some cases, solar panels are mounted directly on the roof. However, this is also a sub-optimal solution because the sun will never be perpendicular to the solar panel. In Worcester, MA, the sun is at an angle of 80° above the horizon at noon during the summer and only 30° above the horizon at noon during the winter. 44 It is typically recommended to mount solar panels with a tilt angle that is equal to the latitude for the site location.45 Another approach is to use a solar panel mounting structure that can be changed twice a year, realigning the panel during the winter and the summer. It is essential to predict how much energy will be generated from different panel orientations in order to compare these different solutions and predict the overall energy output from the system. To do this, one must be able to accurately predict the power from the solar panel at any time.
44 GAISMA. [Online] www.gaisma.com. 45 Lenardic, Denis. Solar radiation estimation and site analysis. Atomstromfreie Website. [Online] Greenpeace Energy, September 13, 2008. http://www.pvresources.com/en/location.php.
Θtilt
Θtilt
Θinc
Θsun
The tilt angle is represented above by Θtilt, which is the angle between the solar panel and the ground. This angle is also the angle between the vertical y-axis and a vector normal to the surface of the solar panel. It is shown in both places in the diagram above. The angle between the y-axis and a vector representing the sun’s rays coming onto the surface of the solar panel is represented by Θsun. Subtracting these two values yields the value for Looking at this as a two dimensional problem the amount of energy from the sun that hits the solar panel at any given moment is related to the size of the solar panel times the cosine of the incident angle between the solar panel and the sun’s rays. The incidental power, or actual power, can be determined based on the amount of power that would land on the surface of the solar panel using the equation below.
Since the sun moves not only vertically in the sky but also across the sky from east to west, this concept must be extended to three dimensions in order to get the instantaneous power throughout the day.
To determine what the optimal tilt angle for solar panel installation is, a group from Taiwan created a simulation that used a Genetic Algorithm (23). They simulated the amount of power
generated by the solar panel at five minute intervals using historic weather data for five years. They could then estimate the amount of energy that would have been generated by the solar panels over that time period at a given tilt angle. To find the optimal tilt angle, they created a pool of genes (binary strings) that represented the tilt angle. With each iteration of the program, a selection process is applied, selecting only the best performing solution. The genes then reproduce. Some are direct copies of the previous generation, other experience a mutation, where one bit changes between 0 and 1. Still others experience crossing over, where a substring from one gene is switched with a substring of another. With each generation, the program gets closer to finding an optimal solution. A similar experiment could be done for Worcester, MA, however the difference in power output between this new solution and the usual recommendation of using the Latitude as your angle is likely to be insignificant, as was the case in this experiment.
Appendix B: Recommended Bidding Process
The first step in the bidding process is defining the system the church wants. This needs to include all the specific details including the amount of power the church hopes to generate, the preferred brands of panels, and the DC/AC inverter. This is also the time to determine the areas on the roof which are suitable for mounting panels. Much of the decision should be made by this point as to what the church is willing to install and pay for in order to make providing information to potential contractors simpler. The second step is to gather a list of local contractors that are known to install similar systems in the area. This is as simple as contacting the MTC for a list of installers in the Worcester area or using a phonebook’s yellow pages. It is important to get a list of installers and to determine which of them are interested in putting in a bid for an installation of this size. After a simple phone conversation with each of them, the church should have a list of contractors that are interested in bidding on their project. These first two steps are mostly covered by this report. The report has a recommended system and location on the roof already selected to meet the needs of the church. The report also includes a list of potential installers in the Worcester area. To complete these two steps, the church only needs to agree to the recommended system and call the installers to make a list of those that are interested. The third step in the process is to draft formal letters requesting bids. These letters need to include very detailed information to simplify the process. First of all, there need to be timetables involved. They should include a deadline for the church to receive the quotes from installers, as well as preferred beginning and ending dates for the installation. It’s also important to give all the details determined in step one of the process. It is best to give as much information as possible so that the church does not need to field calls from contractors seeking more information.
Figure 24: 25kW System Cash Flow with Volunteer Installation Figure 8 depicts the total cash flow of the 25kW array with volunteer installation. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7.6 Assessment:
Revisiting the scenarios above, cost of installation is the single most important factor in whether a system will be feasible. Currently, the cost-per-watt of solar panels is generally fixed at $4-$5. This allows minor room to reduce the cost. However, because installation is not necessarily a fixed cost and most of the work can be done by knowledgeable volunteers it is possible to keep this cost much lower.
Another noticeable result of analyzing these scenarios is that the systems of varying sizes all have a break-even point of approximately nineteen years. The main reason for this phenomenon is the fact that larger arrays, despite their greater initial investment, recover savings much quicker because of their greater electricity production. The 25kW array may generate $164,997.40 in the course of 25 years compared to a smaller, 10kW array which may only produce $65,998.96 of revenue. This observation
displays the fact that a larger solar array is much more beneficial in the long term; however a small one is financially easier in the short term.
7.7 Sensitivity Analysis
Although we have determined that a largest array is the optimal scenario for the production of electricity the nine-teen year break-even point is near the system life expectancy of 20-25 years. However the cost of solar cells is constantly decreasing. Based on discussions with solar manufacturers and installers, it is expected that costs for solar panels will fall quickly in the next three to five years and the payback period will thus decrease rapidly. To illustrate the effect influence lower costs on the solar market we decided to create a sensitivity analysis. This analysis below offers a fifth scenario that projects possible costs and efficiencies of solar panels in five years. The following is a scenario assumes that in the future, technology will reduce the cost-per-watt of a solar panel from $4.30 to $2.00 and increase the solar cell efficiency from 15% to 20%. The result is a dramatic drop in the amount of time it takes to break-even. The period of time necessary to break-even drops from nineteen years to only nine and the number of panels required to generate the same amount of electricity is reduced from 117 panels to 88. The reduction in the number of panels also reduces the need to install solar panels in sub-optimal locations.
Figure 25: Futuristic 25kW System Cash Flow Figure 9 depicts the total cash flow of a 25kW array purchased in five years. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
Figure 26: The Effect of Waiting 5 Years The chart above depicts the outcome if a 25kW system, scenario three, was purchased in the present time period and if a 25kW system was purchased in five years using the data described above. As the results in figure 10 clearly demonstrate, it would be much more beneficial, economically, to implement a 25kW system after five years rather than at the current time period.
8. Social and Environmental Impact
The significance of solar panel systems go far beyond financial factors. Alternative forms of energy are important to the sustainability of our planet. This section identifies the social and environmental impacts that a solar panel installation would have on the church and what we have done to disseminate information about solar panel installations.
8.1 Effects on Carbon Footprint
A Carbon footprint is a measurement of the impact a person or a building has on the environment. It is usually represented as the number of tons of carbon dioxide released into the atmosphere by things such as power plants, cars, or burning heating oil. Based on information available from the Global Footprint Network, current levels of emissions exceed the capacity that the earth is able to absorb. This rate has been sharply increasing since the 1960s.41 Finding solutions to the problem of increased emissions is critical to environmental sustainability. However, offsetting the world’s carbon emissions by planting trees isn’t an efficient solution to the problem of increased emissions. A better solution is reducing the emissions themselves. Reduction of emissions requires cutting back the use of fossil fuels. This means driving less, using cars that are more efficient, and meeting high standards for emissions testing. It also means using less electricity, and when possible looking for ‘green’ alternatives. Sources of environmentally friendly electricity include solar PV, wind energy, and hydroelectric; although hydroelectric plants significantly disrupt the river upon which they are built.
41 Global Footprint Network. Globalfootprintnetwork.com. [Online] [Cited: December 2, 2008.] http://www.footprintnetwork.org/en/index.php/GFN/page/carbon_footprint/.
The church’s carbon footprint is primarily made up of the electricity it consumes, and the natural gas used for heating. Based on the formulas used by the Global Footprint Network the annual
electricity consumption creates 59 tons of carbon dioxide.42 The total amount of carbon dioxide created by or on behalf of the church is at least 67 tons of CO2 emissions per year.2 If the church were to install a 25kW solar array, they would significantly reduce the their annual emissions to 39 tons of CO2, a thirty three percent reduction.
42 Global Footprint Network. Globalfootprintnetwork.com. [Online] http://www.carbonfootprint.com/carbonfootprint.html 43 Harper Collins Publishers. (2009). The Green Bible. Retrieved 3/1, 2009 from http://greenletterbible.com/
8.2 Environmental Stewardship
Wesley United Methodist Church commissioned this study of green technology as an expression of its commitment towards “environmental stewardship.” Many of the individuals who participate in the church feel that it is their responsibility to the community to contribute to the adoption of clean energy. For that reason, the implementation of a solar array would not only reduce green house emissions, but also spread awareness to the wider community and inspire other community members to follow suit. As stewards of the Earth, a church could send a powerful message to the community by acting on these values in their place of worship.
Green stewardship is rapidly becoming a popular topic in the Christian community. There is a new bible that has been printed called the “Green Bible”. It highlights eco-friendly passages in green and has an index in the back where one can look up “green” passages. It is said that the “Green Bible sets out an urgent agenda for the Christian community.”43 One particularly relevant passage from Leviticus is as follows, “You shall not strip your vineyard bare, or gather the fallen grapes of your vineyard; you shall leave them for the poor and the alien: I am the Lord your God”. Another moving passage in support of green stewardship is from Psalm 24, “The earth is the Lord’s and everything in it, the world, and all who live in it.”
Green stewardship is a movement within the church that is rapidly gaining momentum as more and more Christians become aware of the threat humans pose to the planet. As the earth’s destruction continues, many are starting to feel it is part of their calling as followers of God to help. The city of Worcester has many churches of many faiths each concerned about the cost of rising electricity as well as the benefits of helping the environment. If the Wesley United Methodist Church were to decide to implement a solar system, it would be recognized as one of the first churches in the area to do so and demonstrate its leadership as an environmental steward in the community. If the implementation of green energy proves to be beneficial the Wesley United Methodist Church will become an example to those in Worcester and New England.
8.3 Informational Brochure
An informational brochure has been created to spread information to the church about the benefits of solar panel installations. Our correspondence with a Methodist Church from Maine showed us that the spread of information about a solar panel project can greatly reduce opposition and build support for this costly expenditure. The brochure captures the essence of our results. It has financial information, including a graph about the amount of energy produced with a large scale system and a graph showing how the payback period is directly related to the system cost per watt. The brochure also includes a couple of passages from the bible that support the concept of green stewardship and accompanying pictures of God’s magnificent creation. The brochure can be found in Appendix M: Informational Brochure.
8.4 Survey
After our final presentation, given on March 1, 2009, we handed out a brief survey to those who were in attendance (Appendix N). The audience consisted primarily but not exclusively of members of the Board of Trustees and Finance Committee at Wesley. There were only fourteen people in
attendance, so the survey is of little statistical value; however it has helped us to realize some of the general perceptions held by the congregation. All fourteen people responded they felt that investment in alternative energy is important, however their reasons for this answer varied. Some cited green stewardship as their primary reason, while others pointed to the fact that there is a finite supply of fossil fuels. Still others felt that alternative energy was important so that the country could become independent of foreign oil. Most mentioned that it was important to be environmentally conscious and many responses included a combination of these reasons. In response to the second question, which asked about what the public’s perception of a solar panel installation on Wesley United Methodist Church would be, the answers were again unanimous. All responses stated that the public’s view of such an installation would be positive. One responder felt that it would have limited affect, and only be slightly positive, while many responded that this would be “very positive”, “forward thinking”, and “green.” The last two questions had a wider range of responses than the first two. When asked whether or not a solar panel installation should be pursued even if there was no economic gain, most said that it should be pursued for environmental reasons, however, there were a few responses that said that the only factor that was important to them was the financial savings.
Finally, on the last question, which asked whether or not Wesley United Methodist Church should pursue a solar installation now, in the future, or not at all, there was the widest disparity of answers. A number of people felt that the church should wait for five years and then reevaluate the situation, while others felt that church should do more research about it now. Some people felt that the church should absolutely pursue it now, while there was one response that said it should not be pursued at all.
While everyone in attendance of our final presentation felt that alternative energy was important, it can be seen by looking at the remainder of the questions that this belief was weighted differently by each person. Looking into the future, the congregation will have a lot to debate as they try to decide what to do with the results of this project.
9. Conclusions and Recommendations
The benefits of solar panel installations are numerous, ranging from green stewardship to reducing the church’s carbon footprint, and from building a strong public image for the church to reducing the church’s monthly electricity bills. The feasibility of such a system is not determined by a financial analysis alone. Based on current prices, a solar panel system installed at Wesley United Methodist church would have a nine-teen year payback period. We recommend that the church strongly weigh the positive impacts of solar panels alongside the economic feasibility of installation. With the present conditions, it is unlikely that a solar panel installation will lose money over the lifetime of the system; however, it requires a large capital investment and has a slow payback. The church should monitor future the economic conditions using the “Simplified Economics Spreadsheet for Wesley United Methodist Church” that we have provided to get an estimate of economic feasibility of a solar power system. When it is determined that the benefits from a solar panel installation outweigh its drawbacks, such as when the cost per watt drops below a threshold price, the church should follow the procedure outlined below:
1. Form a committee of people who are interested in seeing this project carried forward. 2. Have the committee hold meetings/focus groups with interested members of the congregation to educate the congregation about solar panels and answer any concerns. The committee can use our presentation, brochure, and any of the other materials in this report. 3. Have the committee members contact three to five installers and go through the bidding process as we have outlined.
4. Use the graph “Simplified Economics Spreadsheet for Wesley United Methodist Church” with current data to determine the financial feasibility of this system.
After estimates have been received, the selection process can begin. After choosing an installer, the rest of the process, such as acquiring the Commonwealth Solar rebate and fulfilling permit obligations will be handed by the chosen installer. Hopefully, as solar panel technology continues to drop in price, the church will be able to reap the benefits of clean, renewable energy.
Appendix A: Solar Panel Tilt Analysis
Analysis of the installation orientation of solar panels is crucial to getting the highest power output from the solar panels. Solar panels receive the most energy from the sun when the surface of the solar panel is perpendicular to the sun’s rays. Some solar panels track the position of the sun. The surface of these panels is always perpendicular to the sun, giving tracking panels the highest output of any mounting system. However, the increase in efficiency does not come without a cost. Tracking mounting systems are significantly more expensive than other mounting options and are also a lot more likely to break.
In some cases, solar panels are mounted directly on the roof. However, this is also a sub-optimal solution because the sun will never be perpendicular to the solar panel. In Worcester, MA, the sun is at an angle of 80° above the horizon at noon during the summer and only 30° above the horizon at noon during the winter. 44 It is typically recommended to mount solar panels with a tilt angle that is equal to the latitude for the site location.45 Another approach is to use a solar panel mounting structure that can be changed twice a year, realigning the panel during the winter and the summer. It is essential to predict how much energy will be generated from different panel orientations in order to compare these different solutions and predict the overall energy output from the system. To do this, one must be able to accurately predict the power from the solar panel at any time.
44 GAISMA. [Online] www.gaisma.com. 45 Lenardic, Denis. Solar radiation estimation and site analysis. Atomstromfreie Website. [Online] Greenpeace Energy, September 13, 2008. http://www.pvresources.com/en/location.php.
Θtilt
Θtilt
Θinc
Θsun
The tilt angle is represented above by Θtilt, which is the angle between the solar panel and the ground. This angle is also the angle between the vertical y-axis and a vector normal to the surface of the solar panel. It is shown in both places in the diagram above. The angle between the y-axis and a vector representing the sun’s rays coming onto the surface of the solar panel is represented by Θsun. Subtracting these two values yields the value for Looking at this as a two dimensional problem the amount of energy from the sun that hits the solar panel at any given moment is related to the size of the solar panel times the cosine of the incident angle between the solar panel and the sun’s rays. The incidental power, or actual power, can be determined based on the amount of power that would land on the surface of the solar panel using the equation below.
Since the sun moves not only vertically in the sky but also across the sky from east to west, this concept must be extended to three dimensions in order to get the instantaneous power throughout the day.
To determine what the optimal tilt angle for solar panel installation is, a group from Taiwan created a simulation that used a Genetic Algorithm (23). They simulated the amount of power
generated by the solar panel at five minute intervals using historic weather data for five years. They could then estimate the amount of energy that would have been generated by the solar panels over that time period at a given tilt angle. To find the optimal tilt angle, they created a pool of genes (binary strings) that represented the tilt angle. With each iteration of the program, a selection process is applied, selecting only the best performing solution. The genes then reproduce. Some are direct copies of the previous generation, other experience a mutation, where one bit changes between 0 and 1. Still others experience crossing over, where a substring from one gene is switched with a substring of another. With each generation, the program gets closer to finding an optimal solution. A similar experiment could be done for Worcester, MA, however the difference in power output between this new solution and the usual recommendation of using the Latitude as your angle is likely to be insignificant, as was the case in this experiment.
Appendix B: Recommended Bidding Process
The first step in the bidding process is defining the system the church wants. This needs to include all the specific details including the amount of power the church hopes to generate, the preferred brands of panels, and the DC/AC inverter. This is also the time to determine the areas on the roof which are suitable for mounting panels. Much of the decision should be made by this point as to what the church is willing to install and pay for in order to make providing information to potential contractors simpler. The second step is to gather a list of local contractors that are known to install similar systems in the area. This is as simple as contacting the MTC for a list of installers in the Worcester area or using a phonebook’s yellow pages. It is important to get a list of installers and to determine which of them are interested in putting in a bid for an installation of this size. After a simple phone conversation with each of them, the church should have a list of contractors that are interested in bidding on their project. These first two steps are mostly covered by this report. The report has a recommended system and location on the roof already selected to meet the needs of the church. The report also includes a list of potential installers in the Worcester area. To complete these two steps, the church only needs to agree to the recommended system and call the installers to make a list of those that are interested. The third step in the process is to draft formal letters requesting bids. These letters need to include very detailed information to simplify the process. First of all, there need to be timetables involved. They should include a deadline for the church to receive the quotes from installers, as well as preferred beginning and ending dates for the installation. It’s also important to give all the details determined in step one of the process. It is best to give as much information as possible so that the church does not need to field calls from contractors seeking more information.
Figure 22: 25kW System Cash Flow Figure 6 depicts the total cash flow of the 25kW array. The
37 “Commonly Observed Degradation in Field-Aged Photovoltaic Modules.” Quitana, M.A.; King, D.L..; McMahon, T.J. and Osterwald, C.R.
Figure 13: Solar panel efficiency over time
Based on these two studies, we have decided to use the average of their results, and estimate 0.6% annual degradation.
Because solar panels contain no moving parts maintenance costs are found to be extremely minimal. Due to the fact that the lifetime warranties of solar panels are generally found to be twenty years or more, it is unlikely that any maintenance costs will be realized within this time span. The cost of maintaining an array will generally reside in labor, not replacement parts. Thus, maintenance costs for solar systems are estimated at costing 4% of the initial system cost.38 The “Incentives and Rebates” section is straightforward and its content is taken directly from MTC’s economic spreadsheet. It describes the total MTC rebate based on the system size, whether or not the building is public (churches are not considered public in this case), and whether or not the components are manufactured in Massachusetts. This rebate will most likely be $3.25 per Watt for Wesley United Methodist Church. Unfortunately, the MTC rebate is the only incentive applicable to the church, because all other aid is in the form of tax incentives.
38A Rural Electric Co-op’s Experience with Photovoltaic Systems for Livestock Water Pumping, Skinner, Rolland http://www.usda.gov/rus/electric/engineering/sem2002/skinner.htm
Section five, “Financing” allows the option for testing how the feasibility of a system changes by using a loan. This section requires the percentage of the entire loan that the down payment makes up, the interest rate, and the loan term. It assumes that a fixed rate mortgage will be used, and calculates the monthly payment. If you wish to not use any financing, simply put down that the down payment makes up 100% of the loan.
Section six deals with energy cost. The current cost of electricity was based on recent electricity bills from Wesley United Methodist Church. Current electric rates are $0.16 per kWh. The energy cost adjustor, or the amount that electricity costs will increase each year was determined based on historical data from the Energy Information Administration39. Data for the national average cost per kWh from 1973 to 2007 was taken and plotted to show the trend over time.
39 Average Retail Prices of Electricity, Energy Information Administration http://www.eia.doe.gov/emeu/mer/prices.html
Figure 14: Historical prices of the national average cost per kWh.
We initially expected an exponential increase in energy cost, or a certain percentage per year, however, the data clearly shows a linear increase of about $0.0018 per year. It is possible, and in fact likely, that energy costs will increase more rapidly in the future, though, as we begin to run out of fossil fuels. However, we will use the historical data as a way to predict future increases. The data above is taken at a national level and the costs of electricity can vary at a local level, based on the competition between companies, demand, and distribution fees, however, energy price trends happen at a national level. We have addressed this by taking the starting value for our predicted energy costs to be the present cost of electricity from one of Wesley United Methodist Church’s recent bills. We then estimated that this current cost of $0.16 per kWh would increase at a rate of $0.0018 kWh per year as the national data predicts.
The last section in the economic spreadsheet requiring input is the “Economic Factors” section, which calls for an estimation of the average inflation. This was determined by looking at historical data for the Consumer Price Index (CPI)40. The CPI was at 10 in 1914, and ended up at 217 in 2008. The percent change in the CPI from year to year was dramatically different, as shown below.
40 U.S. Department Of Labor, Bureau of Labor Statistics.
Figure 15: The year to year percent change in the Consumer Price Index. Solving the traditional compound interest formula for the interest rate, we found that typical inflation is 3.29% per year. A graph comparing the value of $10 by 1914 standards can be seen below, comparing the actual inflation with this estimate of 3.29% per year.
Figure 16: The amount of money required to have the same value as $10 in 1914. By comparing the two graphs, we see that although it is very difficult to predict what the CPI will be in a given year, over long periods of time, such as the length of this solar panel investment, the average rate of 3.29% is a good estimation. By obtaining these parameters from historical data, measurements, or by professionals in the business, we have given ourselves the tools necessary to analyze the feasibility of different solar panel systems. The next section in this report, “Scenarios”, will use what we have outlined here to expand upon the feasibility details of certain photovoltaic systems.
7. Scenarios
To correctly assess the feasibility and impact this project would have on the church a number of practical scenarios were generated. These scenarios are analyzed using the economic spreadsheet in the economic context presented in chapter six. In each scenario, the system size is varied. In order to accommodate a larger system size, different installation procedures are necessary.
7.1 Assumptions and Selection of Solar Panels
The first objective in creating a list of practical scenarios was to determine the base assumptions. The summation of these assumptions is then factored into each scenario to build a base by which all scenarios can be assembled on. By taking this approach we limit the number of changing variables to more correctly display the affect that each scenario has on the outcome of the entire project. The assumptions listed below are values that extend those found in the Economic Context section. 100% Down Payment: After discussing with the financial representative at Wesley United Methodist Church we discovered the church holds no debt. Thus, there is no reason to take out a loan to pay for the system. The church representative assured us that if a system was purchased, it could be paid either through gifts or through a trust fund. Using Kyocera’s KC200GT Solar Panel:
One of the most critical choices in constructing a solar panel array is the choice of which solar panel to use. To choose the most practical panel available a list of potential solar panels was constructed and from that list the panel with the best credentials was taken. This list compounded several important factors, the most important of which were: energy production, cost-per-watt, and panel size. Based on
these factors, the recommended panel was Kyocera’s KC200GT. This panel embodied high energy production, 200 Watts, low cost-per-watt at $4.35, and relatively small footprint. 42 degree solar panel array tilt: Another critical factor in determining how much energy is realized by the solar panel array is the tilt of the panel relative to the sun. Throughout the year the sun’s position changes every month. For solar panels, the optimum tilt is the one that is perpendicular to the incident angle of the sunlight. However, for this system, the panels would not be mechanically tracking the sun, instead they are manually set. The conclusion to this problem was to tilt the panels at 42 degrees, the exact latitude of the Worcester area. This provides the best energy production for non moving arrays. Sunny Boy Inverters: For system sizes 25kW and less, the Sunny Boy line provides a very inexpensive inverter to match the output of a chosen array size. As discussed in Chapter 5, the Sunny Boy products are effective in price, efficiency, and reliability and fits quite nicely in the following scenario sizes. Using these inverters, we estimated a total DC to AC conversion factor of 79.49%. This factor was a result of the inverter efficiency as well as the efficiency of the AC and DC wiring and connections to the system. Combining the efficiency of the solar panels and the efficiency of the DC to AC conversion, we calculated an overall system efficiency of 11.92%.
7.2 Scenario 1: Small System Size:
First we investigated the smallest system available. This system, while humble in size, must still be capable of providing a moderate percentage (10%-15%) of power to the church. However, due to the church’s large energy usage, a small system might actually be considered large in other applications. For the “Small System” scenario we chose to implement a 10kW system.
Characteristics:
One of the most notable advantages to constructing a small solar panel system is the fact that it comes with a small capital cost. The initial system cost was calculated to be $49,000.00 after the appropriate rebates are applied. This system consisted of forty seven solar panels ($40,898.00) and two SB4000US DC-to-AC inverters ($5,370.00) with the installation accounting for the remaining cost. The entire system spanned 126.42 square meters and required very few, if any, elevated platforms. The greatest disadvantage of small solar array is the fact it provides such a small percentage of the total power consumed by the church. This solar array will produce less than one-sixth of the energy that the church is currently consuming and will take nineteen years to payback its initial cost. A system with such a long payback period is also susceptible to being quickly outdated by new and improved technology.
Impact:
Figure 17: 10kW System Energy Production
The chart above depicts the energy consumed by The Wesley United Methodist Church, seen in blue, and the electricity produced by the 10kW solar array, seen in red. The total “net” usage is seen in green which is the difference between the energy consumed and the energy produced.
Figure 18: 10kW System Cash Flow Figure 2 depicts the total cash flow of the 10kW array. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7. 3 Scenario 2: Moderate System Size:
The second system we chose to investigate was a moderately-sized solar array. The goal of this system was to provide more electricity than the smaller apparatus while not drastically increasing cost. This system must be capable of providing approximately 20% of the churches electricity consumption. For the “Moderate System” scenario we chose to implement a 15kW system.
Characteristics:
The advantages to a 15kW system are that it produces much more electricity than its smaller system counter-part. In addition, the cost of constructing such a system is relatively inexpensive when
compared to the larger systems. To carry out such a system would require a total initial payment of $72,750.00 after rebates, consist of 70 solar panels ($60,900.00), two SB6000US inverters ($7,450.00) and installation costs. The system would be capable of producing slightly less than one quarter of the energy consumption of the church. With an increase in the number of solar panels on the roof of Wesley United Methodist Church, it becomes apparent that space is limited. A majority of the seventy solar panels, occupying 188.28 square meters, will need to be raised on an elevated platform to avoid shadowing affects. In addition to being space-limited, the “Moderate system” scenario will take nineteen years to pay off.
Impact:
Figure 19: 15kW System Energy Production The chart above depicts the energy consumed by The Wesley United Methodist Church, seen in blue, and the electricity produced by the 15kW solar array, seen in red. The total “net” usage is seen in green which is the difference between the energy consumed and the energy produced.
Figure 20: 15kW System Cash Flow Figure 4 depicts the total cash flow of the 15kW array. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7.4 Scenario 3: Maximum System Size:
The third scenario maximized the number of solar panels that could be placed on roof. The energy produced by smaller systems is almost trivial compared to the total power consumption by the church. Thus, the goal of this system is to provide the most electricity possible using the maximum roof space available. For the “Maximum System” scenario we chose to implement a 25kW system.
Characteristics:
The greatest advantage of a large system is the large power output. A 25kW system is capable of producing more than one-fourth the church’s electricity, and, at various times, almost one third the total power consumption. Based on current costs, the maximum system size also has a payback period of nineteen years, the same as the modernly sized system found in the previous section: nineteen years. Although the system payback period is equivalent to the last three scenarios, this example produces a
much higher cash flow: averaging around $6,800 per year compared to $4,000 for the moderate system and $2,800 for the smallest system. The greatest disadvantage to this system is the cost to implement. Constructing a system of this size takes an initial $120,250.00 of capital investment, consisting of 117 solar panels ($101,790.00), three SB7000US inverters ($12,057.00) and installation costs. To fit 117 panels on the roof of the church requires elevating almost all of the panels and placing several of them on the slated section of the roof.
Impact:
Figure 21: 25kW System Energy Production The chart above depicts the energy consumed by The Wesley United Methodist Church, seen in blue, and the electricity produced by the 25kW solar array, seen in red. The total “net” usage is seen in green which is the difference between the energy consumed and the energy produced.
Figure 22: 25kW System Cash Flow Figure 6 depicts the total cash flow of the 25kW array. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7.5 Scenario 4: Maximum System Size with Volunteer installation:
The final scenario produced assumed that the installation cost could be reduced by using volunteers to provide most of the necessary labor. Labor is the most significant cost involved in installing a solar panel array besides the cost of the system itself. The only requirement is that a licensed electrician supervises the electrical work.
Characteristics:
As stated in the section above, a solar system of this magnitude is capable of producing more than one fourth the energy consumption of the church. With volunteer work the system initial cost drops drastically from $120,250.00 to $41,057.00. The return on investment drops from nineteen years to only six! The disadvantage to implementing such a large system is the need for elevated platforms for
each panel. One hundred and seventeen solar panels require all the flat space on the roof including the slated area.
Figure 13: Solar panel efficiency over time
Based on these two studies, we have decided to use the average of their results, and estimate 0.6% annual degradation.
Because solar panels contain no moving parts maintenance costs are found to be extremely minimal. Due to the fact that the lifetime warranties of solar panels are generally found to be twenty years or more, it is unlikely that any maintenance costs will be realized within this time span. The cost of maintaining an array will generally reside in labor, not replacement parts. Thus, maintenance costs for solar systems are estimated at costing 4% of the initial system cost.38 The “Incentives and Rebates” section is straightforward and its content is taken directly from MTC’s economic spreadsheet. It describes the total MTC rebate based on the system size, whether or not the building is public (churches are not considered public in this case), and whether or not the components are manufactured in Massachusetts. This rebate will most likely be $3.25 per Watt for Wesley United Methodist Church. Unfortunately, the MTC rebate is the only incentive applicable to the church, because all other aid is in the form of tax incentives.
38A Rural Electric Co-op’s Experience with Photovoltaic Systems for Livestock Water Pumping, Skinner, Rolland http://www.usda.gov/rus/electric/engineering/sem2002/skinner.htm
Section five, “Financing” allows the option for testing how the feasibility of a system changes by using a loan. This section requires the percentage of the entire loan that the down payment makes up, the interest rate, and the loan term. It assumes that a fixed rate mortgage will be used, and calculates the monthly payment. If you wish to not use any financing, simply put down that the down payment makes up 100% of the loan.
Section six deals with energy cost. The current cost of electricity was based on recent electricity bills from Wesley United Methodist Church. Current electric rates are $0.16 per kWh. The energy cost adjustor, or the amount that electricity costs will increase each year was determined based on historical data from the Energy Information Administration39. Data for the national average cost per kWh from 1973 to 2007 was taken and plotted to show the trend over time.
39 Average Retail Prices of Electricity, Energy Information Administration http://www.eia.doe.gov/emeu/mer/prices.html
Figure 14: Historical prices of the national average cost per kWh.
We initially expected an exponential increase in energy cost, or a certain percentage per year, however, the data clearly shows a linear increase of about $0.0018 per year. It is possible, and in fact likely, that energy costs will increase more rapidly in the future, though, as we begin to run out of fossil fuels. However, we will use the historical data as a way to predict future increases. The data above is taken at a national level and the costs of electricity can vary at a local level, based on the competition between companies, demand, and distribution fees, however, energy price trends happen at a national level. We have addressed this by taking the starting value for our predicted energy costs to be the present cost of electricity from one of Wesley United Methodist Church’s recent bills. We then estimated that this current cost of $0.16 per kWh would increase at a rate of $0.0018 kWh per year as the national data predicts.
The last section in the economic spreadsheet requiring input is the “Economic Factors” section, which calls for an estimation of the average inflation. This was determined by looking at historical data for the Consumer Price Index (CPI)40. The CPI was at 10 in 1914, and ended up at 217 in 2008. The percent change in the CPI from year to year was dramatically different, as shown below.
40 U.S. Department Of Labor, Bureau of Labor Statistics.
Figure 15: The year to year percent change in the Consumer Price Index. Solving the traditional compound interest formula for the interest rate, we found that typical inflation is 3.29% per year. A graph comparing the value of $10 by 1914 standards can be seen below, comparing the actual inflation with this estimate of 3.29% per year.
Figure 16: The amount of money required to have the same value as $10 in 1914. By comparing the two graphs, we see that although it is very difficult to predict what the CPI will be in a given year, over long periods of time, such as the length of this solar panel investment, the average rate of 3.29% is a good estimation. By obtaining these parameters from historical data, measurements, or by professionals in the business, we have given ourselves the tools necessary to analyze the feasibility of different solar panel systems. The next section in this report, “Scenarios”, will use what we have outlined here to expand upon the feasibility details of certain photovoltaic systems.
7. Scenarios
To correctly assess the feasibility and impact this project would have on the church a number of practical scenarios were generated. These scenarios are analyzed using the economic spreadsheet in the economic context presented in chapter six. In each scenario, the system size is varied. In order to accommodate a larger system size, different installation procedures are necessary.
7.1 Assumptions and Selection of Solar Panels
The first objective in creating a list of practical scenarios was to determine the base assumptions. The summation of these assumptions is then factored into each scenario to build a base by which all scenarios can be assembled on. By taking this approach we limit the number of changing variables to more correctly display the affect that each scenario has on the outcome of the entire project. The assumptions listed below are values that extend those found in the Economic Context section. 100% Down Payment: After discussing with the financial representative at Wesley United Methodist Church we discovered the church holds no debt. Thus, there is no reason to take out a loan to pay for the system. The church representative assured us that if a system was purchased, it could be paid either through gifts or through a trust fund. Using Kyocera’s KC200GT Solar Panel:
One of the most critical choices in constructing a solar panel array is the choice of which solar panel to use. To choose the most practical panel available a list of potential solar panels was constructed and from that list the panel with the best credentials was taken. This list compounded several important factors, the most important of which were: energy production, cost-per-watt, and panel size. Based on
these factors, the recommended panel was Kyocera’s KC200GT. This panel embodied high energy production, 200 Watts, low cost-per-watt at $4.35, and relatively small footprint. 42 degree solar panel array tilt: Another critical factor in determining how much energy is realized by the solar panel array is the tilt of the panel relative to the sun. Throughout the year the sun’s position changes every month. For solar panels, the optimum tilt is the one that is perpendicular to the incident angle of the sunlight. However, for this system, the panels would not be mechanically tracking the sun, instead they are manually set. The conclusion to this problem was to tilt the panels at 42 degrees, the exact latitude of the Worcester area. This provides the best energy production for non moving arrays. Sunny Boy Inverters: For system sizes 25kW and less, the Sunny Boy line provides a very inexpensive inverter to match the output of a chosen array size. As discussed in Chapter 5, the Sunny Boy products are effective in price, efficiency, and reliability and fits quite nicely in the following scenario sizes. Using these inverters, we estimated a total DC to AC conversion factor of 79.49%. This factor was a result of the inverter efficiency as well as the efficiency of the AC and DC wiring and connections to the system. Combining the efficiency of the solar panels and the efficiency of the DC to AC conversion, we calculated an overall system efficiency of 11.92%.
7.2 Scenario 1: Small System Size:
First we investigated the smallest system available. This system, while humble in size, must still be capable of providing a moderate percentage (10%-15%) of power to the church. However, due to the church’s large energy usage, a small system might actually be considered large in other applications. For the “Small System” scenario we chose to implement a 10kW system.
Characteristics:
One of the most notable advantages to constructing a small solar panel system is the fact that it comes with a small capital cost. The initial system cost was calculated to be $49,000.00 after the appropriate rebates are applied. This system consisted of forty seven solar panels ($40,898.00) and two SB4000US DC-to-AC inverters ($5,370.00) with the installation accounting for the remaining cost. The entire system spanned 126.42 square meters and required very few, if any, elevated platforms. The greatest disadvantage of small solar array is the fact it provides such a small percentage of the total power consumed by the church. This solar array will produce less than one-sixth of the energy that the church is currently consuming and will take nineteen years to payback its initial cost. A system with such a long payback period is also susceptible to being quickly outdated by new and improved technology.
Impact:
Figure 17: 10kW System Energy Production
The chart above depicts the energy consumed by The Wesley United Methodist Church, seen in blue, and the electricity produced by the 10kW solar array, seen in red. The total “net” usage is seen in green which is the difference between the energy consumed and the energy produced.
Figure 18: 10kW System Cash Flow Figure 2 depicts the total cash flow of the 10kW array. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7. 3 Scenario 2: Moderate System Size:
The second system we chose to investigate was a moderately-sized solar array. The goal of this system was to provide more electricity than the smaller apparatus while not drastically increasing cost. This system must be capable of providing approximately 20% of the churches electricity consumption. For the “Moderate System” scenario we chose to implement a 15kW system.
Characteristics:
The advantages to a 15kW system are that it produces much more electricity than its smaller system counter-part. In addition, the cost of constructing such a system is relatively inexpensive when
compared to the larger systems. To carry out such a system would require a total initial payment of $72,750.00 after rebates, consist of 70 solar panels ($60,900.00), two SB6000US inverters ($7,450.00) and installation costs. The system would be capable of producing slightly less than one quarter of the energy consumption of the church. With an increase in the number of solar panels on the roof of Wesley United Methodist Church, it becomes apparent that space is limited. A majority of the seventy solar panels, occupying 188.28 square meters, will need to be raised on an elevated platform to avoid shadowing affects. In addition to being space-limited, the “Moderate system” scenario will take nineteen years to pay off.
Impact:
Figure 19: 15kW System Energy Production The chart above depicts the energy consumed by The Wesley United Methodist Church, seen in blue, and the electricity produced by the 15kW solar array, seen in red. The total “net” usage is seen in green which is the difference between the energy consumed and the energy produced.
Figure 20: 15kW System Cash Flow Figure 4 depicts the total cash flow of the 15kW array. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7.4 Scenario 3: Maximum System Size:
The third scenario maximized the number of solar panels that could be placed on roof. The energy produced by smaller systems is almost trivial compared to the total power consumption by the church. Thus, the goal of this system is to provide the most electricity possible using the maximum roof space available. For the “Maximum System” scenario we chose to implement a 25kW system.
Characteristics:
The greatest advantage of a large system is the large power output. A 25kW system is capable of producing more than one-fourth the church’s electricity, and, at various times, almost one third the total power consumption. Based on current costs, the maximum system size also has a payback period of nineteen years, the same as the modernly sized system found in the previous section: nineteen years. Although the system payback period is equivalent to the last three scenarios, this example produces a
much higher cash flow: averaging around $6,800 per year compared to $4,000 for the moderate system and $2,800 for the smallest system. The greatest disadvantage to this system is the cost to implement. Constructing a system of this size takes an initial $120,250.00 of capital investment, consisting of 117 solar panels ($101,790.00), three SB7000US inverters ($12,057.00) and installation costs. To fit 117 panels on the roof of the church requires elevating almost all of the panels and placing several of them on the slated section of the roof.
Impact:
Figure 21: 25kW System Energy Production The chart above depicts the energy consumed by The Wesley United Methodist Church, seen in blue, and the electricity produced by the 25kW solar array, seen in red. The total “net” usage is seen in green which is the difference between the energy consumed and the energy produced.
Figure 22: 25kW System Cash Flow Figure 6 depicts the total cash flow of the 25kW array. The figure describes the trend of savings from the initial purchase in year one to the life expectency of a solar array, year 25.
7.5 Scenario 4: Maximum System Size with Volunteer installation:
The final scenario produced assumed that the installation cost could be reduced by using volunteers to provide most of the necessary labor. Labor is the most significant cost involved in installing a solar panel array besides the cost of the system itself. The only requirement is that a licensed electrician supervises the electrical work.
Characteristics:
As stated in the section above, a solar system of this magnitude is capable of producing more than one fourth the energy consumption of the church. With volunteer work the system initial cost drops drastically from $120,250.00 to $41,057.00. The return on investment drops from nineteen years to only six! The disadvantage to implementing such a large system is the need for elevated platforms for
each panel. One hundred and seventeen solar panels require all the flat space on the roof including the slated area.
We developed an economic feasibility spreadsheet
to or greater than 175 Watts are ideal for a project of this magnitude. Last year alone the church consumed 102,000 kWh of electricity. To even begin to offset a fraction of the electricity used a solar system must be powerful enough to produce enough electricity to be viable. In conjunction with this, a minimum allowed solar cell efficiency was established at 10%. A higher efficiency also allows the solar cells to produce its maximum power output more than a lower efficiency counter-part in the same amount of sunlight. The size limitations arise from the desire to keep the panels as small as possible. Because space is a limited commodity the panels that occupy the space must be kept small to allow for more panels in the limited space. Smaller panels also provide a bonus when discussing shadow effects. Shadows that are cast on a given solar panel render that entire panel obsolete. A small shadow may render a large array useless. Having a larger number of smaller panels decreases the chance that a small shadow will create such detrimental effects as compared to the larger panel. In addition to size, weight was considered to ensure that the panel could be structurally supported by the rooftop without any unforeseen consequences. The weight limit was determined by questioning the building inspector on all possible points on the rooftop.
Model
Power
Price
$/Watt
L (in)
W (in)
H (in)
W/in^2
Weight
Efficiency
Kyocera’s KD200GT
200W
$870
$4.35
56.2
39
1.4
0.09
40.7
15.00%
Sun power Corp.’s SPR-315
315W
$1510
$4.80
61.39
41.18
1.81
0.12
53
19.30%
Sharp’s ND-V230A1
230
$1,150
$5.00
64.6
39.1
1.8
0.09
44.1
14.00%
Table 3: Potential Solar Panels
The table above displays three of the most promising photovolatics for utilization in no particular order.
5.2 Inverter Choice
Unlike the photovoltaic selection choice, inverters had a much smaller pool to choose from. Many inverters were found to either in the midrange, 3000W-7000W output, or in a commercial range, 100000W or above. Because the list of possible choices was so small, all types of inverters were added to the component matrix. This gave us the opportunity to contrast having one large inverter compared to several smaller inverters. Knowing that the maximum energy that could be utilized by filling the Church’s roof entirely with panels was approximately 25000W it became apparent that the much larger inverters were overkill. Inverters such as Satcon’s AE30, was capable of connecting up to 37500W to the grid. This meant that even if we were capable of covering the roof with panels we would only be utilizing 66% of the inverters capacity. On the other hand, smaller inverters such as Sunny Boy’s SB7000US would require three inverters to handle the electrical output of the solar array. While this may seem unfavorable, it actually carries many advantages. First, smaller inverters can be used to precisely match the power output of the photovoltaic array. This means that there is approximately 100% utilization of the inverters compared to only 66% when using Satcon’s AE30. In addition, one AE30 would cost $33,780.00 to handle 25000W of electricity, while three SB7000US would cost only $12,057.00, more than half the price. Another benefit to having smaller inverters is the ability to region the array. This means the array, in its entirety, can be broken into several smaller, independent parts. This method avoids a total shutdown of the array system if a single inverter fails. Finally, a smaller inverter increases maintainability when compared to a large commercial inverter. If a large inverter requires replacement it may take days or even weeks to swap out, not to mention the assistance of a professional. A smaller inverter is generally much simpler
to operate and maintain. The SB7000US is actually capable of being carried to the site and is simple enough to be installed by someone with elementary electrical knowledge. The table below shows a list of possible inverters.
Model
Efficiency
Power (W)
Current (A)
Cost
$/Watt
Sunny Boy’s SB7000US
95.00%
7000
34
$4,019.00
$0.57
Sunny Boy’s SB6000US
95.00%
6000
29
$3,725.00
$0.62
Fronius IG 4500-LV
94.40%
4500
21.6
$2,899.99
$0.64
Table 4: Potential Inverters Once it became apparent that smaller inverters were more beneficial in this situation than their larger, commercial counter-parts, it was only a matter of reducing cost to arrive at the chosen inverter. Above is a table which represents the top three chosen inverters for Wesley United Methodist Church.
6. Economic Context
We developed an economic feasibility spreadsheet in Microsoft Excel as described in the Methodology section to aid us in feasibility calculations for various scenarios. In the Methodology section we explained how the spreadsheet worked. An accurate economic model depends not only on accurate formulas, but on various parameters that can be estimated with a high degree of certainty, backed by historical figures or measurements. This section explains our justification for the parameters that we entered into the spreadsheet. A screenshot of the spreadsheet can be seen below.
Figure 12: A screenshot of the economics spreadsheet. In the first section of the spreadsheet, “System Size and Cost” we are required to determine the cost per Watt of the solar panels and the cost of the inverter and other equipment. This data comes directly from our list of solar panels and our inverters and is explained in depth in the section titled “Possible Solar Panels and Placements”.
The second section, “Installation and Fees”, describes an estimated cost for installation on a per Watt basis, an estimation of electrical inspection costs, and several other fees. The installation cost per Watt is the largest factor in determining system cost, so it must be estimated with high precision. We used the average cost for a solar system, installation and component costs combined, of $8.03 provided by the MTC36 and subtracted out the component cost to leave us with our installation cost alone.
36 Massachusetts Technology Collaborative. Information on installers and costs. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS%20Installer-Cost-Location%20Data%20for%20Website%20as%20of%2001-31-09.xls
Unfortunately, without getting an actual bid from contractors, this is the most accurate estimate we cost estimate we can get. We also came in correspondence with some installers, who confirmed the rate of $8.00 per watt and gave us a further cost breakdown. A summary of these correspondences can be found in “Appendix X: Correspondence”. Section three titled “System Life and Maintenance” provides an estimation of the system life expectancy, the yearly degradation factor, and the yearly maintenance cost. To use a safe estimate of system life expectancy, we chose twenty-five years, as that is the typical warranty on solar panels. It could be the case that the system continued to work after twenty-five years; however we would rather use a conservative estimate and analyze the feasibility over the next twenty-five years. The yearly degradation factor is the percentage that the electricity production is decreased each year, due to several factors such as: packaging material disintegration, adhesional degradation, interconnect loss of integrity, moisture intrusion, and semiconductor device degradation.
Unfortunately, an effort to collect data regarding photovoltaic degradation has not been well coordinated. There are, however, two studies that look at degradation on single and multicrystalline photovoltaics. The Sandia study, which was on multicrystalline photovoltaics, reported 0.5% degradation per year. The National Renewable Energy Laboratory reported 0.7% degradation per year on a study they did looking at single and multicrystalline photovoltaic. The graph below shows what the overall efficiency of a solar panel would be over the course of twenty five years, assuming it started at 13% efficiency37.
Model
Power
Price
$/Watt
L (in)
W (in)
H (in)
W/in^2
Weight
Efficiency
Kyocera’s KD200GT
200W
$870
$4.35
56.2
39
1.4
0.09
40.7
15.00%
Sun power Corp.’s SPR-315
315W
$1510
$4.80
61.39
41.18
1.81
0.12
53
19.30%
Sharp’s ND-V230A1
230
$1,150
$5.00
64.6
39.1
1.8
0.09
44.1
14.00%
Table 3: Potential Solar Panels
The table above displays three of the most promising photovolatics for utilization in no particular order.
5.2 Inverter Choice
Unlike the photovoltaic selection choice, inverters had a much smaller pool to choose from. Many inverters were found to either in the midrange, 3000W-7000W output, or in a commercial range, 100000W or above. Because the list of possible choices was so small, all types of inverters were added to the component matrix. This gave us the opportunity to contrast having one large inverter compared to several smaller inverters. Knowing that the maximum energy that could be utilized by filling the Church’s roof entirely with panels was approximately 25000W it became apparent that the much larger inverters were overkill. Inverters such as Satcon’s AE30, was capable of connecting up to 37500W to the grid. This meant that even if we were capable of covering the roof with panels we would only be utilizing 66% of the inverters capacity. On the other hand, smaller inverters such as Sunny Boy’s SB7000US would require three inverters to handle the electrical output of the solar array. While this may seem unfavorable, it actually carries many advantages. First, smaller inverters can be used to precisely match the power output of the photovoltaic array. This means that there is approximately 100% utilization of the inverters compared to only 66% when using Satcon’s AE30. In addition, one AE30 would cost $33,780.00 to handle 25000W of electricity, while three SB7000US would cost only $12,057.00, more than half the price. Another benefit to having smaller inverters is the ability to region the array. This means the array, in its entirety, can be broken into several smaller, independent parts. This method avoids a total shutdown of the array system if a single inverter fails. Finally, a smaller inverter increases maintainability when compared to a large commercial inverter. If a large inverter requires replacement it may take days or even weeks to swap out, not to mention the assistance of a professional. A smaller inverter is generally much simpler
to operate and maintain. The SB7000US is actually capable of being carried to the site and is simple enough to be installed by someone with elementary electrical knowledge. The table below shows a list of possible inverters.
Model
Efficiency
Power (W)
Current (A)
Cost
$/Watt
Sunny Boy’s SB7000US
95.00%
7000
34
$4,019.00
$0.57
Sunny Boy’s SB6000US
95.00%
6000
29
$3,725.00
$0.62
Fronius IG 4500-LV
94.40%
4500
21.6
$2,899.99
$0.64
Table 4: Potential Inverters Once it became apparent that smaller inverters were more beneficial in this situation than their larger, commercial counter-parts, it was only a matter of reducing cost to arrive at the chosen inverter. Above is a table which represents the top three chosen inverters for Wesley United Methodist Church.
6. Economic Context
We developed an economic feasibility spreadsheet in Microsoft Excel as described in the Methodology section to aid us in feasibility calculations for various scenarios. In the Methodology section we explained how the spreadsheet worked. An accurate economic model depends not only on accurate formulas, but on various parameters that can be estimated with a high degree of certainty, backed by historical figures or measurements. This section explains our justification for the parameters that we entered into the spreadsheet. A screenshot of the spreadsheet can be seen below.
Figure 12: A screenshot of the economics spreadsheet. In the first section of the spreadsheet, “System Size and Cost” we are required to determine the cost per Watt of the solar panels and the cost of the inverter and other equipment. This data comes directly from our list of solar panels and our inverters and is explained in depth in the section titled “Possible Solar Panels and Placements”.
The second section, “Installation and Fees”, describes an estimated cost for installation on a per Watt basis, an estimation of electrical inspection costs, and several other fees. The installation cost per Watt is the largest factor in determining system cost, so it must be estimated with high precision. We used the average cost for a solar system, installation and component costs combined, of $8.03 provided by the MTC36 and subtracted out the component cost to leave us with our installation cost alone.
36 Massachusetts Technology Collaborative. Information on installers and costs. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS%20Installer-Cost-Location%20Data%20for%20Website%20as%20of%2001-31-09.xls
Unfortunately, without getting an actual bid from contractors, this is the most accurate estimate we cost estimate we can get. We also came in correspondence with some installers, who confirmed the rate of $8.00 per watt and gave us a further cost breakdown. A summary of these correspondences can be found in “Appendix X: Correspondence”. Section three titled “System Life and Maintenance” provides an estimation of the system life expectancy, the yearly degradation factor, and the yearly maintenance cost. To use a safe estimate of system life expectancy, we chose twenty-five years, as that is the typical warranty on solar panels. It could be the case that the system continued to work after twenty-five years; however we would rather use a conservative estimate and analyze the feasibility over the next twenty-five years. The yearly degradation factor is the percentage that the electricity production is decreased each year, due to several factors such as: packaging material disintegration, adhesional degradation, interconnect loss of integrity, moisture intrusion, and semiconductor device degradation.
Unfortunately, an effort to collect data regarding photovoltaic degradation has not been well coordinated. There are, however, two studies that look at degradation on single and multicrystalline photovoltaics. The Sandia study, which was on multicrystalline photovoltaics, reported 0.5% degradation per year. The National Renewable Energy Laboratory reported 0.7% degradation per year on a study they did looking at single and multicrystalline photovoltaic. The graph below shows what the overall efficiency of a solar panel would be over the course of twenty five years, assuming it started at 13% efficiency37.
hold the greatest chance of success.
A brochure was created in order to inform the congregation about the benefits of solar panels as well as address some of the questions that may arise in regards to an installation on the roof of their church. It was important for this brochure to be informative as well as succinct. Outlining key financial, environmental and social benefits was the most important feature of the brochure. It was also important to judge the congregation’s receptiveness to a photovoltaic system. In order to measure their views, we created a survey that was oriented towards the leadership group of the Wesley United Methodist Church that attended our final presentation (Appendix N). The survey focused on how members of the congregation felt about having solar panels installed on their church. It was important to measure how the congregation felt about the installation of solar panels in general. This was used to determine if it was the receptiveness of solar panels in general that caused the congregation to react in a particular way, or rather the installation of solar panels on their church in particular. We also wanted to access from this survey if members of the congregation felt that the social benefits of installing such a system could outweigh the economic benefits. That is, we wanted to know if the church would still install a solar panel system if there were limited or no economic incentive to do so. The survey was designed to maximize the the opportunities for qualitative responses to open-ended questions. The goal was to make the survey so that it could be completed in a few minutes.
In addition to determining the overall feasibility of installing solar panels on the Wesley United Methodist church, a secondary goal of this project was to promote the awareness of solar panel systems the greater Worcester community. To achieve this, it was important to create a set of information that could be presented and distributed to the community. This final presentation included information
about solar panels in general, the steps required to determine their economic impact and get them installed, and reasons why solar panel systems are beneficial both economically and to the environment.
4. Site Analysis
This chapter is concerned with the physical conditions of the church and area around it that would affect the installation of a solar panel system. The nature of a solar array requires that the site analysis take into account the physical structure and layout of the roof space, as well as the weather. The weather plays an important role with such a system, determining the amount of sunlight that can be gathered by the panels and converted into energy. After a brief introduction to the location of the church, this chapter begins by discussing the meteorological findings for the area in which the church is located. The next section describes the physical layout of the roof space. This is followed by an analysis of the Church’s energy usage, and a look into the installation process.
4.1 Location of the Church
The Wesley United Methodist Church is located near the heart of Worcester Massachusetts. When traveling down Main Street the United Methodist Church becomes apparent as you approach the Johnson Tunnel, between State Street and Gertrude Ave. The church is located on 114 Main Street and resides at approximately 42.3 degrees latitude and -71.8 longitude. The building is four stories tall and formed primarily out of grey brickwork.
4.2 Meteorological Analysis
One of the greatest challenges in determining the feasibility of a solar project is determining the amount of energy that is provided by the sun. For solar panels, the primary factor of whether or not a project is feasible is the amount of sunlight a chosen area receives. To calculate this, many factors must be considered: average sunny days, clearness of the weather, precipitation, average sun duration, and latitude. To find how each of these factors effects the overall conclusion, tedious calculations must be done. Weather data from previous years need to be consolidated and then averages can be calculated
from this data. Fortunately, much of this information is readily available. The United States Renewable Resource Energy Data Center (RREDC) contains all the information needed to address these factors.32 One of the most useful ratings provided by the U.S Renewable Resource Data Center is the insolation graph. This graph displays the average solar energy per square meter per day in any given month. This value is calculated from thirty years of data gathering and is extremely useful when calculating the energy that can potentially be generated if solar panels are installed. From RREDC's website many different insolation graphs can be calculated. The website provides the user with three options. The first is what type of data to be displayed. This value can either be: average, minimum, or maximum. The second option is which month’s data to view. The user is given an option of choosing a specific month out of the twelve, or the annual reading, which provides an average. Finally, the third option specifies how the solar panels are to be orientated. Because Worcester is located at approximately 42 degrees latitude, the choice of orientation could drastically change the insolation values. For this project, the solar panels can be oriented southward at latitude. On the following page is a graph of the United States generated from RREDC's website which encompasses the average annual solar radiation for south facing panels. Each region on the map relates to a specific insolation value, where higher is better. In the case of Worcester, this area falls within the average of 3 to 5 kWh/m2/day.
32 RReDC. U.S. Solar Radiation Resource Maps. Renewable Resource Data Center. [Online] National Renewable Energy Laboratory. http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/
Expanding on the information above, the GAISMA organization also provides in-depth analysis of monthly insolation values. 33 By selecting the Worcester area, GAISMA provides a plethora of solar information from sunrise and sunset times, sun path diagrams, and solar energy and surface meteorology. While much of the information is enlightening, the most valuable statistic is the "insolation, kWh/m2/day" value found in the solar energy section. The GAISMA organization provides a very simple breakdown of insolation values for each month during the year. The difference between GAISMA's data and RREDC's is the fact that GAISMA provides a precise numerical value where RREDC only provides a range between two integers.
33 GAISMA. [Online] www.gaisma.com
Figure 9: Mean Daily Irradiation for Worcester
Using the data we have collected concerning insolation values, we are now capable of determining an approximate output of the panels. For example, when the project was in its infant stages, we estimated we had 270 square meters to work with. We then wanted to determine what the average energy was available to that given area. To calculate this we multiplied an insolation value of a specific month by the area available. The result is in kWh per day. Currently, the average efficiency of a solar panel is approximately 10%, so we multiplied our result by 10%. The result is an average amount of energy we could hope to acquire in a day if we covered the entire area with solar panels of an appropriate power rating. To determine what the average energy would be in a month we multiply this value by the number of days in the month. The result is a value that we can use to directly compare with electricity bill's consumption value sent monthly by the local energy provider. The benefit of determining this is that we can determine if the energy produced by that area is enough to meet, or exceed the church’s current consumption.
4.3 Layout of Roof Space
The primary roof space that would potentially be used for the solar panel array is a mostly flat area that is about 55 feet wide and 80 feet long. The area has an open southern exposure that makes it ideal for solar power collection. The flat part of the roof is situated in such a way that it is sunny with few shadows throughout the day, and anything mounted to the roof would not affect the aesthetics of the building from most angles, particularly Main Street in front of the building.
The flat roof area is covered with a white rubberized roofing material. In the center of the main open area are two large skylights (shaded black in the drawing), which take up space and cannot be removed or covered with panels. There is a third skylight mounted to the side of the north sloped roof. To the west side of the large open area is another section of sloped roof that rises above the flat roof about 20 feet. This creates a separate flat section that is primarily shaded by the sloped roof and the large chimney. On the east side is the sloped roof that runs parallel to Main street in front of the church and will completely block anything on the flat roof from view. The southern exposure is open to the side street next to the church building, but the height of the building blocks anything not on the edge of the roof from view. In the northwest corner is an elevated flat portion about 40 feet taller than the rest. This 20 foot by 40 foot section is almost entirely in the sun throughout the day and is covered in the same white rubberized material. It’s accessible by a ladder mounted to the wall, and is somewhat isolated from the rest of the roof area. This makes it somewhat less convenient to use. There is internal access to the main portion of the roof, making inspections, repairs and snow removal easier. This would also facilitate in monitoring the solar panels.
4.4 Energy Usage
Due to the church’s size and daily activities it is no surprise that the Wesley United Methodist church uses a significant amount of electricity. Currently the church uses an average amount of 9500 kWh of energy a month; which totals to $1300 dollars a month in electricity costs. It is apparent why the church has sought cheaper, renewable energy to offset electricity cost.
To correctly assess the impact of renewable energy sources, such as solar panels, we determined the church’s past and present electricity usage. The easiest method for determining the consumption trends from month to month is using past electricity bills. After consolidating electricity usage bills for one year in 2007 we created the graph below to help visualize the months of greatest
demand. This graph displays the amount of energy consumed, in kWh, from month to month. From the graph, it can be seen that although there are not huge fluctuations in the amount of energy needed by the church, certain months, such as August and December, have higher energy demands. This may be due to factors such as air conditioning in the summer, and the increased need for lighting along with holiday activities in December.
Figure 10: Wesley United Methodist Church’s Electricity Consumption Using the meteorological data from section 4.2, we compared the energy consumption data of the church to the amount of energy that could be produced by a solar panel system. Although in chapter 7 we discuss a number of scenarios corresponding to various system sizes, the graph below demonstrates a system size of twenty kW. The blue bars in the graph represent the monthly energy demands of the church, as in the previous graph. The red bars represent the amount of energy that can be produced by a 20kW system. The difference between these two, which corresponds to the net energy demand after installing such a system, is displayed in green.
0
2000
4000
6000
8000
10000
12000
January
February
March
April
May
June
July
August
September
October
November
December
kWh
Month
Energy Usage and Production -20 kW System
Energy Used
Energy Produced
Net Usage
Figure 11: Power Consumption vs. Energy Production of a 20 kW System From this graph, it can be seen that the system displayed does not produce enough electricity to fully offset the demands of the church. Because of the very large energy demand required by the church, coupled with the amount of irradiation in the Worcester area, it would take system that is larger than could be supported by the available roof space. So although it is unlikely that the church will be able to sell any excess energy back to the utility company, the amount produced could defer a considerable fraction of their overall energy demands.
4.5 The Installation Process
Because the church has a newly installed membrane roof on its flat areas, installation on this portion of the roof should be relatively simple. The mounting structure for the panels can be directly connected to the roof and sealed to maintain insulation. These portions of the roof are rated for 35 lbs per square foot, which should not be exceeded.
The slanted portions of the roof, however, are covered in slate. If any solar panels were to be put on this area of the roof, we would recommend removing the slate tiles on these portions. This is because the fragility of slate requires that it be given higher level of maintenance. For example, cracked tile may need to be replaced. If solar panels were mounted on a slate portion of the roof that needed to be repaired, significant work would need to be done in order to fix the underlying slate. Also, the installation procedure for mounting panels on a slate roof is more complex, and the tilt angle of the panels is restricted to the slope of the roof.
It is important that during the installation process all necessary electrical and building codes are adhered to. Certain requirements are also stated by Commonwealth Solar in their minimum technical requirements.34 These include the use of a Massachusetts licensed electrician to do all of the electrical work, making sure all wiring modifications are properly insulated, and that the system can be disconnected for maintenance. Another aspect of the installation process is tying the solar panel system into the electric grid. This allows the excess electricity produced by the system to flow into the local electrical grid to be used by other members of the grid. This process begins by completing an interconnection agreement with the local utility company. The utility company reviews the project to make sure that it will have no negative impacts on the grid. The utility company, town and local inspectors, and the contractor installing the system are all involved in this process. It is best to begin the interconnection process during the final design stages of the system, but before construction, due to the level of technical detail needed by the utility company in order to assess the installation’s possible effects.
34 Massachusetts Technology Collaborative. Commonwealth Solar Rebate Program. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS_AttachmentDMinimumTechnicalRequirements_v3_010109.pdf
In order to give the church the information necessary to pursue an installation if they found it to be feasible, we created a list of installers who would be able to install such a system. This list can be seen in Appendix. The list was compiled using information in a
spreadsheet of Massachusetts solar panel installers provided by Commonwealth Solar.35 Installers were then selected based on the costs of their installations, the size and scope of previous installations, and reviews and recommendations gathered from our various correspondences.
35 Massachusetts Technology Collaborative. Information on Installers and Costs. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS%20Installer-Cost-Location%20Data%20for%20Website%20as%20of%2001-31-09.xls
5. Possible Solar Panels and Inverters
One of the most important factors in devising a photovoltaic array is determining which solar panels to purchase and what type of inverter to utilize for the situation at hand. To correctly assess which panels and which inverters would make greatest impact on our feasibility solution for the Wesley United Methodist Church a component matrix was conceived. The component matrix contains pertinent information about potential photovoltaic/inverter candidates that have a high chance of success in our solution. The matrix incorporates many of the highest quality products made by various manufactures in the field of solar technology. By consolidating these potential products we are capable of determining which panels or which inverters have benefits over their competitors and how those benefits will affect our goal of feasibility. This chapter is separated in two distinct sections: solar panel choices, and inverter choices. Each section will discuss the criteria used to filter out unwanted components as well as which devices hold the greatest chance of success.
5.1 Solar panels
At first glance, the amount of solar panels available is overwhelming. To overcome this, a set of benchmarks was established and each panel was ranked against the set of criteria. If a given panel ranked poorly it was discarded. Any panel that was moderate or exceptional was added to the matrix of possible panels to be later scrutinized when all variables had been considered. The criteria were comprised of these important attributes: power output, efficiency, size, and weight.
Many selection criteria were initially established out of back of the envelope calculations and later altered when additional variables were realized. Judging by the electrical consumption of the Wesley United Methodist Church as well as the limited amount of space available for solar cells, we concluded that our solar panels must have a power output of at least 175 Watts. Panels that are equal
In addition to determining the overall feasibility of installing solar panels on the Wesley United Methodist church, a secondary goal of this project was to promote the awareness of solar panel systems the greater Worcester community. To achieve this, it was important to create a set of information that could be presented and distributed to the community. This final presentation included information
about solar panels in general, the steps required to determine their economic impact and get them installed, and reasons why solar panel systems are beneficial both economically and to the environment.
4. Site Analysis
This chapter is concerned with the physical conditions of the church and area around it that would affect the installation of a solar panel system. The nature of a solar array requires that the site analysis take into account the physical structure and layout of the roof space, as well as the weather. The weather plays an important role with such a system, determining the amount of sunlight that can be gathered by the panels and converted into energy. After a brief introduction to the location of the church, this chapter begins by discussing the meteorological findings for the area in which the church is located. The next section describes the physical layout of the roof space. This is followed by an analysis of the Church’s energy usage, and a look into the installation process.
4.1 Location of the Church
The Wesley United Methodist Church is located near the heart of Worcester Massachusetts. When traveling down Main Street the United Methodist Church becomes apparent as you approach the Johnson Tunnel, between State Street and Gertrude Ave. The church is located on 114 Main Street and resides at approximately 42.3 degrees latitude and -71.8 longitude. The building is four stories tall and formed primarily out of grey brickwork.
4.2 Meteorological Analysis
One of the greatest challenges in determining the feasibility of a solar project is determining the amount of energy that is provided by the sun. For solar panels, the primary factor of whether or not a project is feasible is the amount of sunlight a chosen area receives. To calculate this, many factors must be considered: average sunny days, clearness of the weather, precipitation, average sun duration, and latitude. To find how each of these factors effects the overall conclusion, tedious calculations must be done. Weather data from previous years need to be consolidated and then averages can be calculated
from this data. Fortunately, much of this information is readily available. The United States Renewable Resource Energy Data Center (RREDC) contains all the information needed to address these factors.32 One of the most useful ratings provided by the U.S Renewable Resource Data Center is the insolation graph. This graph displays the average solar energy per square meter per day in any given month. This value is calculated from thirty years of data gathering and is extremely useful when calculating the energy that can potentially be generated if solar panels are installed. From RREDC's website many different insolation graphs can be calculated. The website provides the user with three options. The first is what type of data to be displayed. This value can either be: average, minimum, or maximum. The second option is which month’s data to view. The user is given an option of choosing a specific month out of the twelve, or the annual reading, which provides an average. Finally, the third option specifies how the solar panels are to be orientated. Because Worcester is located at approximately 42 degrees latitude, the choice of orientation could drastically change the insolation values. For this project, the solar panels can be oriented southward at latitude. On the following page is a graph of the United States generated from RREDC's website which encompasses the average annual solar radiation for south facing panels. Each region on the map relates to a specific insolation value, where higher is better. In the case of Worcester, this area falls within the average of 3 to 5 kWh/m2/day.
32 RReDC. U.S. Solar Radiation Resource Maps. Renewable Resource Data Center. [Online] National Renewable Energy Laboratory. http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/
Expanding on the information above, the GAISMA organization also provides in-depth analysis of monthly insolation values. 33 By selecting the Worcester area, GAISMA provides a plethora of solar information from sunrise and sunset times, sun path diagrams, and solar energy and surface meteorology. While much of the information is enlightening, the most valuable statistic is the "insolation, kWh/m2/day" value found in the solar energy section. The GAISMA organization provides a very simple breakdown of insolation values for each month during the year. The difference between GAISMA's data and RREDC's is the fact that GAISMA provides a precise numerical value where RREDC only provides a range between two integers.
33 GAISMA. [Online] www.gaisma.com
Figure 9: Mean Daily Irradiation for Worcester
Using the data we have collected concerning insolation values, we are now capable of determining an approximate output of the panels. For example, when the project was in its infant stages, we estimated we had 270 square meters to work with. We then wanted to determine what the average energy was available to that given area. To calculate this we multiplied an insolation value of a specific month by the area available. The result is in kWh per day. Currently, the average efficiency of a solar panel is approximately 10%, so we multiplied our result by 10%. The result is an average amount of energy we could hope to acquire in a day if we covered the entire area with solar panels of an appropriate power rating. To determine what the average energy would be in a month we multiply this value by the number of days in the month. The result is a value that we can use to directly compare with electricity bill's consumption value sent monthly by the local energy provider. The benefit of determining this is that we can determine if the energy produced by that area is enough to meet, or exceed the church’s current consumption.
4.3 Layout of Roof Space
The primary roof space that would potentially be used for the solar panel array is a mostly flat area that is about 55 feet wide and 80 feet long. The area has an open southern exposure that makes it ideal for solar power collection. The flat part of the roof is situated in such a way that it is sunny with few shadows throughout the day, and anything mounted to the roof would not affect the aesthetics of the building from most angles, particularly Main Street in front of the building.
The flat roof area is covered with a white rubberized roofing material. In the center of the main open area are two large skylights (shaded black in the drawing), which take up space and cannot be removed or covered with panels. There is a third skylight mounted to the side of the north sloped roof. To the west side of the large open area is another section of sloped roof that rises above the flat roof about 20 feet. This creates a separate flat section that is primarily shaded by the sloped roof and the large chimney. On the east side is the sloped roof that runs parallel to Main street in front of the church and will completely block anything on the flat roof from view. The southern exposure is open to the side street next to the church building, but the height of the building blocks anything not on the edge of the roof from view. In the northwest corner is an elevated flat portion about 40 feet taller than the rest. This 20 foot by 40 foot section is almost entirely in the sun throughout the day and is covered in the same white rubberized material. It’s accessible by a ladder mounted to the wall, and is somewhat isolated from the rest of the roof area. This makes it somewhat less convenient to use. There is internal access to the main portion of the roof, making inspections, repairs and snow removal easier. This would also facilitate in monitoring the solar panels.
4.4 Energy Usage
Due to the church’s size and daily activities it is no surprise that the Wesley United Methodist church uses a significant amount of electricity. Currently the church uses an average amount of 9500 kWh of energy a month; which totals to $1300 dollars a month in electricity costs. It is apparent why the church has sought cheaper, renewable energy to offset electricity cost.
To correctly assess the impact of renewable energy sources, such as solar panels, we determined the church’s past and present electricity usage. The easiest method for determining the consumption trends from month to month is using past electricity bills. After consolidating electricity usage bills for one year in 2007 we created the graph below to help visualize the months of greatest
demand. This graph displays the amount of energy consumed, in kWh, from month to month. From the graph, it can be seen that although there are not huge fluctuations in the amount of energy needed by the church, certain months, such as August and December, have higher energy demands. This may be due to factors such as air conditioning in the summer, and the increased need for lighting along with holiday activities in December.
Figure 10: Wesley United Methodist Church’s Electricity Consumption Using the meteorological data from section 4.2, we compared the energy consumption data of the church to the amount of energy that could be produced by a solar panel system. Although in chapter 7 we discuss a number of scenarios corresponding to various system sizes, the graph below demonstrates a system size of twenty kW. The blue bars in the graph represent the monthly energy demands of the church, as in the previous graph. The red bars represent the amount of energy that can be produced by a 20kW system. The difference between these two, which corresponds to the net energy demand after installing such a system, is displayed in green.
0
2000
4000
6000
8000
10000
12000
January
February
March
April
May
June
July
August
September
October
November
December
kWh
Month
Energy Usage and Production -20 kW System
Energy Used
Energy Produced
Net Usage
Figure 11: Power Consumption vs. Energy Production of a 20 kW System From this graph, it can be seen that the system displayed does not produce enough electricity to fully offset the demands of the church. Because of the very large energy demand required by the church, coupled with the amount of irradiation in the Worcester area, it would take system that is larger than could be supported by the available roof space. So although it is unlikely that the church will be able to sell any excess energy back to the utility company, the amount produced could defer a considerable fraction of their overall energy demands.
4.5 The Installation Process
Because the church has a newly installed membrane roof on its flat areas, installation on this portion of the roof should be relatively simple. The mounting structure for the panels can be directly connected to the roof and sealed to maintain insulation. These portions of the roof are rated for 35 lbs per square foot, which should not be exceeded.
The slanted portions of the roof, however, are covered in slate. If any solar panels were to be put on this area of the roof, we would recommend removing the slate tiles on these portions. This is because the fragility of slate requires that it be given higher level of maintenance. For example, cracked tile may need to be replaced. If solar panels were mounted on a slate portion of the roof that needed to be repaired, significant work would need to be done in order to fix the underlying slate. Also, the installation procedure for mounting panels on a slate roof is more complex, and the tilt angle of the panels is restricted to the slope of the roof.
It is important that during the installation process all necessary electrical and building codes are adhered to. Certain requirements are also stated by Commonwealth Solar in their minimum technical requirements.34 These include the use of a Massachusetts licensed electrician to do all of the electrical work, making sure all wiring modifications are properly insulated, and that the system can be disconnected for maintenance. Another aspect of the installation process is tying the solar panel system into the electric grid. This allows the excess electricity produced by the system to flow into the local electrical grid to be used by other members of the grid. This process begins by completing an interconnection agreement with the local utility company. The utility company reviews the project to make sure that it will have no negative impacts on the grid. The utility company, town and local inspectors, and the contractor installing the system are all involved in this process. It is best to begin the interconnection process during the final design stages of the system, but before construction, due to the level of technical detail needed by the utility company in order to assess the installation’s possible effects.
34 Massachusetts Technology Collaborative. Commonwealth Solar Rebate Program. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS_AttachmentDMinimumTechnicalRequirements_v3_010109.pdf
In order to give the church the information necessary to pursue an installation if they found it to be feasible, we created a list of installers who would be able to install such a system. This list can be seen in Appendix
spreadsheet of Massachusetts solar panel installers provided by Commonwealth Solar.35 Installers were then selected based on the costs of their installations, the size and scope of previous installations, and reviews and recommendations gathered from our various correspondences.
35 Massachusetts Technology Collaborative. Information on Installers and Costs. Retrieved 1/15, 2009, from http://www.masstech.org/SOLAR/CS%20Installer-Cost-Location%20Data%20for%20Website%20as%20of%2001-31-09.xls
5. Possible Solar Panels and Inverters
One of the most important factors in devising a photovoltaic array is determining which solar panels to purchase and what type of inverter to utilize for the situation at hand. To correctly assess which panels and which inverters would make greatest impact on our feasibility solution for the Wesley United Methodist Church a component matrix was conceived. The component matrix contains pertinent information about potential photovoltaic/inverter candidates that have a high chance of success in our solution. The matrix incorporates many of the highest quality products made by various manufactures in the field of solar technology. By consolidating these potential products we are capable of determining which panels or which inverters have benefits over their competitors and how those benefits will affect our goal of feasibility. This chapter is separated in two distinct sections: solar panel choices, and inverter choices. Each section will discuss the criteria used to filter out unwanted components as well as which devices hold the greatest chance of success.
5.1 Solar panels
At first glance, the amount of solar panels available is overwhelming. To overcome this, a set of benchmarks was established and each panel was ranked against the set of criteria. If a given panel ranked poorly it was discarded. Any panel that was moderate or exceptional was added to the matrix of possible panels to be later scrutinized when all variables had been considered. The criteria were comprised of these important attributes: power output, efficiency, size, and weight.
Many selection criteria were initially established out of back of the envelope calculations and later altered when additional variables were realized. Judging by the electrical consumption of the Wesley United Methodist Church as well as the limited amount of space available for solar cells, we concluded that our solar panels must have a power output of at least 175 Watts. Panels that are equal
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