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This is a grid-tied system.  If I use more electricity than I produce in a given month, I will pay American Electric Power for the difference at retail prices.  If I produce more electricity than I use, AEP will pay me at wholesale prices.  There are no storage batteries [I won't have to buy them or dispose of them].  I send the surplus power that I produce during the daytime to the utility grid, and get it back at night.

I expect to break even with my net production equal to my net consumption. 

Frequently Asked Questions:

How much does a system like this cost?     About the same as a new car.  If you can afford a new car, but don’t have to buy a new car, you can choose to put a grid-connected photovoltaic (PV) system on your house.

How many people around here have solar electric homes?     This is a very difficult question to answer, because it’s hard to know how many people have ordered solar panels over the internet and installed them on their own.  I would guess that the half-dozen or so certified installers in Ohio have collectively installed a couple hundred grid-connected photovoltaic systems.  These vary in size.  I also suspect that my 4.8 kW system is one of the larger residential systems.  Some idea of the total can also be obtained from the Green Energy Ohio Solar Tour book.

Another way to answer the question is by looking at the national statistics.  This is complicated by the rapid growth in the industry, which leaves information that is only a year old extremely out of date.   51 megawatts (grid-connected PV) were installed in the US in 2004  [with the amount installed increasing at about 35% per year].  Of this amount, 96% was installed in California, New Jersey, Arizona, New York and Massachusetts.  Ohio had a tiny piece of the remaining 4%.  The United States’ share represented only 9% of the world total; Germany and Japan together installed 69%.   Source:  Solarbuzz.com

How long will it take to pay for itself?     From an environmental standpoint, right away.  It will reduce the amount of CO₂ released into the atmosphere by over 3 tons per year, mitigating my family’s contribution to global warming.  From an economic point of view, it’s a long term investment closer to the 20-year warranty on the panels, but it is much less than this if you subtract the resulting increase in the value of the home.  The "Solar Estimator" at FindSolar.com, can be used to calculate the price of a system including this change in home value. 

How do you store the power?  How big are the batteries?     I don’t store the power.  There are no batteries.  When I produce extra power it goes out to the distribution grid and my electric meter runs backwards.  When I use more power than I produce, my meter runs forward.  I’m still connected to American Electric Power’s distribution grid.  

Some systems do have batteries.  In fact, an energy storage system is necessary if you are not connected to the distribution grid.  But if you do use batteries, first you have to buy them, then you have to replace them, and then you have to discard them.  If you are off-grid, you also have to budget your power use so that you don’t max out your system. 

With my grid-connected system, I don’t need to budget power on a minute-by-minute basis.  I only need to break even at the end of the billing period.

On the other hand, without batteries there is no back-up power.  When the grid goes down my lights still go out.

Where does the power go when your meter runs backwards?     It goes to the grid to help the other power producers provide electricity to all users. 

The electric distribution grid works sort of like a bathtub with a dozen or so faucets and thousands of tiny drains.  Each faucet represents a power plant and each drain represents a user (a home or a business).  If the amount of the water flowing in is equal to all of the water flowing out, then the water level stays the same in the tub, neither rising nor falling.  All of the drains get their apportioned amount of water (users get the electrical power they need).  The user doesn’t get his electrical power from a particular power plant any more than the water coming out of one of the drains would come from any particular faucet. 

My house uses electricity (like a drain) and it produces electricity with the solar panels (like a faucet adds water to the bathtub).  This doesn’t have to occur simultaneously as long as other sources and users are able to adjust to the difference.  Sometimes I add more than I use; sometimes I use more than I make (especially at night).

Do you use this to heat your house?     No, it provides my electricity.  Solar space-heating systems and solar water-heating systems exist, but these are different technologies that capture and use the heat from sunlight directly.  My panels generate electricity.

What percentage of your electricity will your system produce?     I hope to break even at 100%.  Whether I will or not depends on how much electricity I need to use and the weather, but it should be close.

How long did it take to install?     It took two days for a trained crew of three people to install.

How did you get your grant?     The installer (Third Sun, Athens, OH) helped me with the application.  One of the conditions of the grant is that the system has to be installed by a certified installer.  So one way to get started is to simply contact a certified Ohio installer.  A list of these is available at the GEO website.    The other way is to contact the Office of Energy Efficiency at the Ohio Department of Development.

Was it hard to apply for the grant?  Not at all, the installer took care of all the details.  The installer wants you to get the grant.  The grant makes it easier for the installer to get you to buy their products and services.  I just had to sign the forms that Third Sun prepared. 

Why did you want to install a photovoltaic system?     I wanted to help the environment and I wanted to be able to do things that require electrical power.  With a PV system I don’t have to choose between these. 

I also wanted to demonstrate to others that alternative energy is not a future technology.  It’s a present day technology.  All we need to do to reduce our dependence on fossil fuels is to grow the alternative energy industries.  

Right now photovoltaic manufacturers can’t keep up with the demand.  But they need to sell more photovoltaic panels before they can afford to invest in more manufacturing capacity.  If they do build capacity, prices will fall, making systems more affordable to more people.  This in turn will increase the demand for even more panels, continuing the spiral. 

Government incentive programs, such as the Ohio Department of Development grants, help to front-load the growth spiral.  They make systems such as mine more affordable until increased manufacturing capacity brings prices down.

Why did you choose a photovoltaic system instead of a solar heating system or a wind generator?    The PV system's high capital investment and slow payoff compared to solar water heating and solar space heating is offset by maximum benefit to the environment.  I'm also a technology guy; I like things that use electricity.  I can keep running computers, machines and toy trains without sacrificing my children's future. 

Wind power may not be practical on many small suburban residential lots at central Ohio wind speeds.  Wind generators need to be well above all obstructions to work efficiently, and there may not be enough room for a tall tower on a suburban lot.   If utility rates continue to increase or alternative energy equipment prices continue to fall, wind generators mounted near roof-level may become practical.  New technology may also be more efficient to operate and to install.  See the new SkyStream 3.7 for an example of new wind technology.

This Fronius IG 5100 inverter in my basement converts DC power from the panels to AC synchronized with the distribution grid.

The prototype system: