Solar Energy
Solar Energy

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Welcome to the Solar Energy page with information about my solar voltaic system which converts the sun's energy into electricity which is used at home and transfered to the electrical grid of San Diego Gas & Electric. Even with government incentives, the pay back time on solar voltaic systems is still long. The prices keep coming down and the price of electricity keeps going up, however. Also, our planet is heating up and our supply of fossil fuels is going down. My advice, jump on in! Help the planet! Solar energy is great! Just have it put up on the roof, sit back and watch your meter spin backwards. My small 12 panel system supplies about 75% percent of our electricity over the course of a year. There is virtually no maintenance. I'm also not putting about 6,000 pounds of carbon dioxide into the atmosphere each year that I would without the solar voltaic system.

I purchased the system in June 2006 from Costco. The price of the equipment including twelve British Petroleum (BP) Solar SX170B 170 Watt PV Modules (made in Maryland) and a PV Powered PVP 2000 Inverter (made in Bend, Oregon) was $13,710, less a $4,710 state incentive, for a total equipment cost of $9,000. Sales tax was $697.50. Installation was $2,800. I received a $2,000 federal income tax credit. The total cost to me was therefore about $10,500. ($10,497.50 to be exact.) There were no added costs. I did not deal directly with the governmental agencies except to sign some papers. The contractor dealt with the state agencies, the City of La Mesa, and San Diego Gas & Electric. It was therefore all very easy from my perspective. The installation was very neat and professional. It did take some time with all the permitting, approval of the state incentives, and scheduling with Solar Systems International, LLC,, in Orange, CA, and the contractor, ACS Construction, LP, in Brea, CA. The system was fully installed and operational on November 10, 2006.

In the year prior to the installation we used about 4,500 kilowatt hours of electricity. In the year since the installation we have used about 1000 kilowatt hours of electricity from San Diego Gas & Electricity. The system in that year will have generated about 3050 kilowatt hours. (I am writing this as of October 25, 2007, shortly before the one year anniversary of the system going into operation. These figures therefore include some projections, but are reasonably accurate.) Our total electricity use this past year was therefore about 4,050 kilowatt hours of which the system provided about 3,050 kilowatt hours or about 75%. Our electricity bills averaged less than $10 per month. In addition to the solar system, we did conserve more electricity than the prior year (about 4,050 kilowatt hours now vs. 4,500 kilowatt hours the prior year). I attribute this to purchasing a new energy efficient refrigerator in the summer of 2006 as well as my older son living in an apartment while at college for part of the year.

Was it worth it? Absolutely! It's an easy question. A clear consensus of atmospheric scientists agrees that global warming is occuring and it is caused by the activity of humans in burning fossil fuels. It is also generally agreed that this will cause significant environmental damage, although exactly what the damage will be is difficult to predict with certainty given the complexity of the problem. The United States Environmental Protection Agency states at Climate Change - Basic Information:

Scientists are certain that human activities are changing the composition of the atmosphere, and that increasing the concentration of greenhouse gases will change the planet's climate. But they are not sure by how much it will change, at what rate it will change, or what the exact effects will be.
It is incumbent on each of us to do our part in reducing the use of fossil fuels, which are also a diminishing non-renewable resource. One easy way to do this is the installation of solar cells.

On a personal economic level it's a closer call. We took efforts to conserve electricity in the first place. Our use of 4,500 kilowatt hours a year before the solar voltaic system compares with a average U.S. household use of about 10,650 kilowatt hours a year. (Figure from Department of Energy, Energy Information Administration, using 2001 figures of 1,140 billion kilowatt hours divided by 107 million households.) Our monthly electricity bill was therefore was only about $50 per month. We are only saving perhaps $500 dollars per year. I would not generally invest $10,000 to make $500 per year and not get back my principal. If we had used more electricity a greater percentage of our payment would have been above the lower baseline rates offered by San Diego Gas & Electric. The marginal savings would hence be greater. Additionally, I suspect electricity costs will rise faster than the general rate of inflation and in the long run the solar system will result in an economic benefit to me. Finally, it does make economic sense for everyone if we were to include the costs associated with global warming, political tensions associated with petroleum use, conventional pollutants associated with fossil fuel use, the dangers inherent with nuclear energy, and the environmental problems associated with hydroelectric power generation. Most of these external costs are not reflected in current electricity rates.

The figures above do point out that the most economical line of defense is to save electricity in the first place. As indicated above, we used 42% of the average United States household use before the solar voltaic system. Part of this may reflect living in the mild climate of southern California. On the other hand, European countries use an average of 4,667 kWh per household per year and Japan uses an average of 5,945kWh per household per year. (Greenpeace - Your Energy Savings. That source also states U.S. household use is 11,209 kWh per year, slightly higher than the 10,650 kWh figure above.) Go to my Energy Conservation page for tips to conserve energy. It's really not painful. It's just commonsense!

What's the future? Solar energy will never be a total solution since the sun doesn't always shine. It can be a significant part of power generation, however. While the Bell Labs discovered photovoltaic cells over 50 years ago, wide scale deployment of it is just beginning. With greater economies of scale one suspects the costs will be coming down. Further, electricity prices will likely rise. It's time to get aboard. Do something for the environment. Do something for your children and grandchildren. Go solar!