Solar power has become a lot cheaper lately, at least where there's plenty of sunshine. A sharp long-term fall in the price of solar cells has led The Economist magazine and others to declare that in sunny areas with high electricity prices, solar power is now cheap enough to compete without government subsidies.
Rory McIlmoil, manager of the energy program at environmental consulting firm Downstream Strategies, says that applies to places such as California.
"In those areas, solar is competing with other sources of energy that have higher electricity prices, which makes it a lot more likely that solar can compete."
The comparison is more difficult in Colorado because rates here are about 30 percent lower than California's. Still, Colorado leads the nation in solar and renewable-energy production.
McIlmoil says the price of building a solar power plant is nearing where it would be competitive with a new coal plant of a similar size. He says both cost more than a natural gas plant, but solar has the advantage of free fuel.
"Natural gas peaker plants have other costs associated with their operation that solar power does not. High fuel and, depending on the size, high maintenance costs for your traditional power plants versus solar power plants."
Peaker plants are auxiliary generating stations meant to kick in when power demand is high.
The U.S. solar industry still depends generally on significant federal subsidies, although McIlmiol points out that overall, the much larger fossil-fuels industries actually receive more in tax breaks. Solar is also limited by the inconsistent nature of sunshine, although he says power storage and flexible use of the grid are easing some of those issues. He says thanks to cheap solar cells, 2010 saw what was then a record level of solar power installed.
"And just one year later, twice that much was installed. Roughly 80 percent of the solar power that currently exists in the United States was installed just over the last three years."
One central criticism of renewable energy sources such as solar power is that they are too expensive. McIlmoil says that's rapidly changing, as solar's explosive growth shows.
More from The Economist is at goo.gl/SIb0d. The magazine also says at current growth rates, wind-generated power will surpass nuclear in about ten years.