All three approaches are rapidly expanding across the country. Despite the Berkeley program being less than two years old, 10 different states have passed legislation allowing their cities to set up a Berkeley-style bond-financed loan program. With the passage of the Waxman-Markey climate bill, the option for cities to set up these programs would become federal law. SunEdison in Maryland is currently active in nine states. SolarCity, which has more than 4,000 customers, is active in California, Arizona and Oregon and has promised to announce additional states after the new year.
Right now it is not possible to lower the overall cost of rooftop solar to “grid parity,” that is, to the same price as electricity from local utility companies, without federal subsidies such as the investment tax credit, which lowers the tax bill of banks financing these projects. Those subsidies, which amount to 30 percent of the cost of a solar installation, are guaranteed for at least eight years. By then, SolarCity and its competitors claim they won’t need them.
“Grid parity is driven by multiple factors,” says Attila Toth, vice president of marketing at SunEdison, including the cost of capital, the cost of panels and their installation, and the intensity of sunlight in a given region. “It will occur in different states at different times, but, for example, we expect that California will be one of the first states in the U.S. to get to grid parity, sometime between three and five years from now.”
While the cost of electricity from fossil fuels has increased 3 to 5 percent a year for the past decade, the cost of solar panels has fallen on average 20 percent for every doubling of its installed base. Grid parity is where these trend lines cross—after that, solar has the potential to power more than just homes. It’s hardly a coincidence that Elon Musk, head of electric car company Tesla Motors, sits on SolarCity’s board of directors.
More Ideas to watch
by Christopher Mims
The Gasoline Garden
It is the next step for biofuels: genetically engineered plant life that produces hydrocarbons as a by-product of its normal metabolism. The result will be fuel—common gasoline, even—using nothing but sunlight and CO2. In July, Exxon Mobil announced plans to spend more than $600 million in pursuit of algae that can accomplish the task. Joule Biotechnologies claims to have already succeeded, although the company has yet to reveal any details of its proprietary system.
Uranium and plutonium are not the only fuels that can power a nuclear reactor. With an initial kick from more traditional fissile materials, thorium can set up a self-sustaining “breeder” reaction that produces uranium 233, which is well suited to nuclear power generation. The process has the added benefit of being resistant to nuclear proliferation, because its end products emit enough gamma rays to make the fuel dangerous to handle and easy to track.
Save Energy with Information
Studies show that simply making customers aware of their energy use lowers it
by 5 to 15 percent. Smart meters allow customers to track their energy consumption minute by minute and appliance by appliance. Countless start-ups are offering the devices, and Google and Microsoft are independently partnering with local utilities to allow individuals to monitor their power usage over the Web.
Wind Power from the Stratosphere
According to a Stanford University study released in July, the high-altitude winds that constantly blow tens of thousands of feet above the earth hold enough energy to supply all of human civilization 100 times over. California’s Sky WindPower has proposed harvesting this energy by building fleets of giant, airborne, ground-tethered windmills, while Italy’s Kite Gen proposes to accomplish the same feat using kites.