Matt Rourke, Associated Press
In this Sept. 14, 2011 photo, Tim Johnson poses for a portrait with solar panels on his roof in Philadelphia. Since March, he has generated 50 percent to 75 percent of his electricity with a set of solar panels on his roof, saving 20 percent on his electricity bills.
The biggest problem with so-called "green" energy is that it is not green. The current best price on solar cells is about $4 per watt, and the chargers, batteries and inverters needed to complete a system add about another $4 per watt.
At today's prices, $8 buys about 100,000 watt-hours of electricity. When you account for latitude and seasonal weather, Salt Lake City receives about five hours per day of equivalent sunlight. This means that a solar installation would require about a half-million calendar hours to break even, or about 55 years, assuming that the system never requires maintenance.
In other words, a solar energy system never gives back as much energy as was required to create it. Green energy indeed.
Michael A. Cosman