Energy efficiency is the ultimate answer
If we're going to survive global warming, there are two things we must do. We have to move in the direction of renewable energy, such as wind and solar power, and we have to improve energy efficiency. You can measure it in different ways-passenger miles per gallon of gas, lumens per watt-but we need to think in terms of doubling efficiency. Not "conservation," which implies sacrifice. Efficiency doesn't involve sacrifice. If you compare a modern refrigerator with one from 1973, which was the year of the OPEC oil embargo, it's bigger, it's gotten rid of CFC refrigerants, its inflation-adjusted price is two thirds less-and it uses 75 percent less energy.

Have we picked all the low-hanging fruit already? There's no evidence for that at all. People wondered about that when refrigerators doubled their efficiency, and we went right on and doubled it again. There's virtually no end in sight. One area of interest right now is standby power. If I go to your house at 3 a.m. on a nice spring night, nothing but the refrigerator is actually "on," but you're probably consuming 80 watts in remote-controlled appliances such as televisions and garage-door openers and in cell-phone chargers. These devices used to draw around three watts each, but the California Energy Commission recently passed regulations that limit them to a half-watt. If you buy a cordless telephone in California in 2008, it will use one fifth the power it did a few years ago-and that will eventually be true everywhere in the world. Which brings me back to my main point: that while we do need to develop renewable-energy supplies, energy efficiency is the quickest and cheapest way to delay global warming.