DESIGNING THE FUTURE

Traditional roofs aren't practical. They degrade from thermal shock and ultraviolet radiation and have to be replaced in 20 years. For the Gap's corporate campus in San Bruno, Calif., we planted a "green roof" of ancient grasses. The roof now damps the sounds of jets from the San Francisco airport. It absorbs storm water, which is important because they have serious issues with storm water there. It makes oxygen, provides habitat, and it's beautiful. We also made a green roof for Ford Motor Co.'s River Rouge plant. It saved Ford millions of dollars in storm-water equipment.

How will you fuel the Chinese cities?

I want to see solar power cheaper than coal, but to get the speed and scale to do that fast, you need a place like China. We're not talking about dinky solar collectors on roofs. Think of square miles of marginal land covered with them. This could drop the cost of solar energy an order of magnitude. And for every job making solar panels, there are four jobs putting them in place and maintaining them. We could import these panels, and for every job the Chinese give themselves, we get four. What a gift. And I guarantee you, China will never be able to capture an American photon. We would have indigenous energy and energy security. And we wouldn't be throwing our money into holes in the ground.

And we wouldn't need nuclear energy.

I love nuclear energy. I just want to make sure it stays where God put it--93 million miles away, in the sun.

Your ideas are really catching on.