There has been much buzz about the water-purifying machine that Segway inventor Dean Kamen demonstrated on the Colbert Report last week (even taking on the bag of Spicy Sweet Chili Doritos that Colbert added). Everyone has been trying to find out more about his claim that "you stick a hose into anything that looks wet … and it comes out … as perfect distilled clean water."

So far as I can tell however, it’s true. (Note: I still haven’t worked out if it can handle volatile organics like gasoline and benzene.)

So what follows are the numbers behind the hype. True to form they are distilled from a number of articles and interviews over the last six years. The most informative being Kamen’s talk at TED in 2002.

It is designed to supply a village with 1,000 liters/day of clean water. (Colbert Report) You can use any water source — ocean, puddle, chemical waste site, hexavalent chrome, arsenic, poison, 50 gallon drum of urine. (Colbert Report) Vapor compression distillation is not new. Doing it in such an incredibly efficient way such that it takes only 2 percent of the power of convention distillers is new. (R&D World and Gizmodo commenter) The are no filters to replace, no charcoal, no anything disposable (just distillation). (Colbert Report) The Slingshot (as its called) can use half the waste heat (450 watts) from a sterling engine electrical generator (prototype also being designed by Kamen’s company) to boil its water. (TED) The heat put into the water is recovered with a "counter-flow heat exchanger" and recycled to heat the next batch of water (that is part of the novel bit). (TED and Gizmodo commenter) Slingshot will be less then 60 lbs. (TED) The prototype slingshot was hand-built for $100K. The goal is to get production units down to $1,000 to $2,000. (CNN) The sterling engine, used as an electrical generator, can produce about 200 watts of power (it will never be more then 20 percent efficient) and 800 watts of waste heat (the waste heat that slingshot uses). TED Later sources say the sterling engine can generate 1 kilowatt or enough power for 70 high-efficiency light bulbs. (CNN) The sterling engine can run on anything that burns, propane or even cow dung. (CNN) The slingshot is a David and Goliath reference aimed at putting water and power back in the hands of the individuals. (AP)



The most interesting comments I came across were to the effect that inventing something great is only half the problem. The other half is getting it to the people who need it in a way that works. Luckily, as Gizmodo commenter enginblue points out, if units came down to $1,000 each, this new wave of micro-lending could have people pooling money to purchase units for groups of entrepreneurs wanting to bring this to their village.

Dean Kamen [The Colbert Report]

First Vid of Dean Kamen’s Miracle Water Distiller [Gizmodo]

Dean Kamen: rolling along, helping students and the third world [TED]

The Segway creator’s next entrepreneurial spin [CNN Money]

To build a better world [R&D Magazine]

Segway inventor drinks his own pee (really) [Orange County Register/AP]

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Video courtesy Comedy Central