Guest Comment: Economics of generating your own solar panel electricity

My wife and I decided that this is the year to start generating our own electricity.

In the first week that our new solar panels were in operation, we generated an average 26 kilowatt hours of electricity per day and used only six.

Our neighbors used the remaining 20 kilowatt hours. Our system feeds the surplus into the grid for general use.

We are not being generous.

Tucson Electric Power (TEP) paid for 42 percent of our up-front costs and credits us for power delivered. We get a $2,000 federal tax credit and a $1,000 state tax credit.

After those credits are realized, we will have paid only 48 percent of the cost.

Of course, we also have the satisfaction of generating power without polluting the environment.

We read all sorts of analyses of the competing costs of electricity generated by burning fossil fuels, wind driven turbines, sun heated boilers and tidal wave action as well as solar panels on our roofs.

From a homeowner’s perspective, of course, the latter is the only option unless you live in isolation in the desert or the ice caps melt in Polar regions and we have the ocean at our door.

The cost issue boils down to up-front cost relative to future cost of electricity and whether we can afford it.

Since we don’t know what electricity may cost in the future, a precise calculation of benefits relative to cost is not possible.

At current electricity rates, the system will pay for itself in 15 years but our contractor projects the break-even point in about 10 years.

The amount of electricity that you can generate depends on the orientation of your roof to the sun. If your orientation is less than fully efficient, TEP will pay less of the cost.

Contractors provide free estimates based on your roof configuration and sun orientation, including an estimate of the TEP contribution.

The out-of-pocket cost depends mainly on the number of solar panels that you need.

For estimates of the effect of solar panels and other changes in your home that you can make to reduce your environmental impact, and an estimate of cost savings of each, check out http://www.lowimpactliving.com on the Internet.

There is remarkable variation in estimates from contractors so it is a good idea to get several estimates.

You can get the contact information for solar contractors at that Web site.

We chose American Solar Electric of Scottsdale based on price, the expertise of their people and their reputation among their customers. They took care of our needs without a glitch.

The real fun part is watching that electric meter run backwards.

Leon S. Robertson, Ph.D., a Green Valley resident, is the author of “Hillbilly to Harvard to Yale,” a memoir of his scientific career. The views expressed are the writer's own and do not reflect those of this newspaper.