Along those lines, Robert Samuelson in the WaPo ably does the math regarding the myth of "clean energy," dismantling the most recent wave of Obama rhetoric in the process:
Unless we shut down the economy, we need fossil fuels. More efficient light bulbs, energy-saving appliances, cars with higher gas mileage may all dampen energy use [by 2035]. But offsetting these savings will be more people (391 million vs. 305 million), more households (147 million vs. 113 million), more vehicles (297 million vs. 231 million) and a bigger economy (almost double in size). Although wind, solar and biomass are assumed to grow as much as 10 times faster than overall energy use, they provide only 11 percent of supply in 2035, up from 5 percent in 2008.Read the whole thing.
There are physical limits on new energy sources, as Robert Bryce shows in his book "Power Hungry: The Myths of 'Green' Energy and the Real Fuels of the Future." Suppose an inventor "found a way to convert soybeans into jet fuel," Bryce writes. "Even with that invention, the conversion of all of America's yearly soybean production into jet fuel would only provide about 20 percent of U.S. jet fuel demand." Jet fuel, in turn, is about 8 percent of U.S. oil use. Similarly, wind turbines have limited potential; they must be supported by backup generating capacity when there's no breeze.