At this point Dean Kamen is used to being called naive. "I'm getting neurotic about people overhyping things," he says, "so let me tell you what it doesn't do." Kamen's caution is understandable. He invented the overpublicized, under- performing superscooter known as the Segway—and was responsible for some of that hype. So when it comes to his latest invention, a low-cost, low-power water purifier designed for the Third World, he wants to be clear: he has no idea how to market it or get it to the people who need it. He just knows it works.
What it does is simple. A few years ago, Kamen was working on an electric generator for use in underdeveloped villages when he noticed that it produced about 1,000 watts of waste heat. Kamen decided to try to use that heat to make clean water. There are 6,000 deaths from contaminated water every day, according to the U.N., and safe water is one of the world's more urgent problems. Kamen's device uses that extra heat to distill water—boil it and condense it.
Nothing new about that—Kamen has invented lots of things, but he didn't invent distillation. The trick is to do it using as little energy as possible. However, 1,000 watts of heat won't boil much water, so Kamen developed a closed system, powered by whatever fuel is at hand, that traps the energy released when the boiled water vapor recondenses. Essentially, he's recycling heat. Result: a low-power, low-maintenance device that will cost around $1,000 to manufacture and makes 10 gal. of drinkable water an hour.
Kamen knows major health organizations probably won't buy into unproved technology, so he's taking his invention on the road. He's exploring distribution strategies in Bangladesh, and later this month he'll head to Africa to meet with Rwanda's President. He knows he has a lot to prove. "I have no credibility," he admits. "We have to get them in the field and document that they work." He believes, perhaps innocently, that he can save a lot of lives. Sometimes when you want to change the world, it helps to be a little naive.