Making Gore's Switch Isn't Quite So Simple

This, of course, is the same message as the one in the giant light-switch commercial: If we work together, we can make this happen. All that's lacking is a good hard political shove.

Er . . . no, we can't. Those who study the U.S. power supply say that there are three key reasons why Gore's plan doesn't seem doable.

1. There's too much ground to make up.

Fossil fuels such as coal, oil and natural gas now provide about 72 percent of all U.S. electrical power. Despite a recent boom in the building of renewable energy "plants" -- U.S. wind-power capacity grew by 45 percent last year alone -- solar, wind and geothermal power still provide less than 3 percent of the country's power.

Many experts say they don't know how you could replace one with the other, at least in a decade. The task would require finding large numbers of sites for wind turbines and solar arrays, which means wading through the kind of not-in-my-backyard fights that have held up turbine projects off Cape Cod and in parts of Appalachia. And it would require factories to produce more: New turbine orders take years to fill, wind industry officials say, and one placed today probably wouldn't be delivered until about 2011.

Even the American Council on Renewable Energy, an industry booster group, has a less ambitious goal than Gore's and a longer time horizon. They envision renewable energy sources supplying 25 percent of the country's total energy by 2025.

"We've built up a certain energy infrastructure over the course of 100 years," said Mark Brownstein of the Environmental Defense Fund. "It's hard to imagine how we would fundamentally redo it over the course of the next ten."

2. The consumers and the energy are too far apart.

The areas of the United States that are richest in renewable-energy potential -- the sun-baked Southwest, the windy Great Plains -- are often far from the coastal cities that need their juice. So any major switch to clean power is going to require new transmission lines to connect the turbines out there and the flat-screen televisions over here.

How many transmission lines? Consider the case of T. Boone Pickens, the oil tycoon who has been running his own commercials calling for investments in clean energy. He wants to build a network of wind farms to catch Great Plains gusts, which might one day provide 20 percent of the country's energy. But he needs a way to get the power to the people who would use it. Doing that, Pickens says, would take a massive line-stringing effort comparable to the construction of the interstate highway system in the 1950s. He thinks that it would cost about $200 billion.