"If you tell the world you're going to do something and they go, ‘Yeah…?' it's probably that you're making an incremental change in something that the world is already doing reasonably well," said renowned inventor Dean Kamen at a May 4, 2009, meeting co-sponsored by the Wilson Center's Environmental Change and Security Program and Program on Science, Technology, America, and the Global Economy. "I'd rather work on the really big stuff."

His track record proves it: He holds more than 400 U.S. and international patents, and his most famous inventions include an implantable insulin pump, a portable dialysis machine, and an artificial arm, as well as the Segway personal transporter.

Kamen now seeks to provide clean water to the 1.1 billion people who lack it with the Slingshot, a washing machine-sized device that uses just 500 watts of electricity to produce 10 gallons of clean water an hour.

Tackling the Big Problems: Water and Power

Kamen's career as an inventor began in high school, when he would invent medical devices for his older brother, a doctor. The Slingshot grew out of a portable dialysis machine Kamen developed for patients with renal failure. After inventing a way to make perfectly sterile water for the dialysis machine, he explored whether he could adapt the water-purification technology for the developing world, where millions of people die each year from dirty water.

The data "take your breath away," said Kamen. More than one billion people lack access to clean water, and 1.6 billion do not have access to electricity. Kamen thought he could address both of these problems with the Slingshot, which uses a Stirling-cycle generator to vaporize and condense the water, removing the impurities.

The generator runs on any kind of fuel, including the methane gas in cow dung, which is readily available in the Bangladeshi villages where Kamen conducted a six-month test of the Slingshot. The generator not only powers the water vaporizer, but also produces enough surplus electricity to power a light, cell phone, and computer for every household in a small village.

The Skepticism of Experts: A Bigger Problem?

In meetings with the World Bank and other international development organizations, Kamen was told that the Slingshot was more expensive than other ways of purifying water, including chlorine tablets, activated-charcoal filters, and reverse-osmosis desalination. But unlike these technologies, the Slingshot:

• Can remove any kind of contaminant from water;
• Does not need filters, membranes, or chemicals; and
• Does not require any technical know-how to use.

Kamen granted that the cheaper technologies might be more practical for urban areas, but argued that the Slingshot could have advantages in remote villages without access to technical expertise or a steady supply of chemicals or other components. He also suggested that microfinance might be a way to overcome the large initial cost of the Slingshot—although he emphasized that his expertise lies in developing the technology, and then partnering with experts who know how to surmount the various barriers to distribution.

"If everything I now say by way of recalling my history here seems to you like I'm frustrated, and angry, and disappointed, it's mostly because I'm frustrated, angry, kinda disappointed," said Kamen, adding, "But you're going to fix all that." Suggestions from audience members included learning from the experiences of venture capitalists who have invested in water technology in the developing world, as well as partnering with the military and defense contractors to manufacture and distribute the Slingshot.

Water, Electricity, and National Security

Kamen suggested that the Slingshot could be used to support U.S. foreign-policy and national-security objectives. For instance, the U.S. armed forces could bring water and electricity to an Afghani village with the Slingshot and Stirling-cycle generator. A telephone and camera mounted on the generator would provide communications technology.

"I would suspect that the Taliban…would be way more worried that everybody in town is happy, and healthy, and has light, and is communicating and showing pictures of everything going on" than about the threat of attack by the United States, said Kamen.

Drafted by Rachel Weisshaar and edited by Meaghan Parker.