NH inventor Kamen eyes Stirling Engine [Archive]

Casey

11-15-2002, 05:24 PM

quote: NH inventor Kamen eyes Stirling Engine

By KATHARINE McQUAID
Union Leader Staff

Local inventor Dean Kamen is inching closer to the creation of a Stirling Cycle Engine that can create enough electricity to run a few household appliances, while at the same time making contaminated water drinkable.

The inventor of the Segway Human Transporter and Homechoice compact dialysis machine discussed his latest world-changing invention on last night’s broadcast of “60 Minutes II.”

“I cannot represent to you that this is done or that it’s doable at no risk . . . but most of the invention that’s required to go from the idea to reality, I believe, we’ve mastered, and we can do this,” the Bedford resident told CBS.

The device allowed news anchor Dan Rather to drink clean water from the Merrimack River in Manchester.

“It tastes clean, but you can’t always tell clean,” Rather said last night after drinking the river water distilled by Kamen’s device in his downtown Manchester laboratory.

The machine used to distill Merrimack River water on the show was large and bulky, but Kamen showed a drawing and plastic model of the portable Stirling Engine he is working on. It’s about the size of a window air conditioner with wheels.

Kamen said he imagines the device will give people in remote villages of India and other third world countries a constant source of clean, safe, drinking water, as well as a central source of electricity.

“It could be used to make a central place where people go to charge batteries for computers or cell phones, where people could get access to electricity so that they could have light at night and, all the while, it could be turning 10 gallons of just about anything into potable water,” Kamen told Rather.

The Stirling Engine, which plays heat against cold to create energy, was invented by Robert Stirling, a 19th century Scottish minister. Basically, it’s a closed box with two chambers, one containing gas. The gas is heated from the outside and expands, driving a piston from the hot chamber into the cold chamber, creating power.

According to the Web site for Kamen’s Manchester-based company DEKA, the Stirling Engine has always had high potential for thermodynamic efficiency, but has been plagued with problems, such as limitation of materials. But technical advances over the last 150 years have allowed all aspects of the engine to be modernized, turning it into “a high performance, high output, efficient machine of the 21st century.”

Kamen told CBS he’s always been interested in the Stirling Engine, and began looking at it as a better energy source for his IBOT, a self-balancing wheelchair that, among other things, can climb stairs.

The version unveiled by Kamen on last night’s program creates about 300 continuous watts of electrical power, according to Rather.

“And as a bonus, creates enough heat to distill contaminated water, making it perfectly drinkable,” he said.