How the Slingshot Water Purifier Works

Plans for the Slingshot

With the help of new technology like the Slingshot, maybe some day everyone will have ready access to clean drinking water.
With the help of new technology like the Slingshot, maybe some day everyone will have ready access to clean drinking water.
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Kamen's company tested the Slingshot in Honduras. By one account, the results were excellent [source: Richardson]. The next step is production. DEKA Research and Development is looking for a financer and a manufacturer to help it make Slingshots. According to one report, Kamen approached several large companies and private foundations for financing, with no success [source: Richardson].

The company is rethinking how to market Slingshots, in one scenario, first selling it to industries for commercial distilling to get it into production. Kamen has also mentioned bodegas in Mexico, imagining regions that can plug the purifier in to a wall outlet but need an inexpensive way to make and distribute clean water [source: Richardson]. The primary goal however remains -- to get the Slingshot to anyone who needs safe drinking water.

Thinking about that goal brings to mind an exhibition that recently ran at the National Design Museum. The exhibition, which is titled "Design for the Other 90 Percent," covers the topic of design for poor populations [source: Smithsonian]. Martin Fisher, a mechanical engineer who worked on development projects in Kenya for more than 17 years, contributed an essay describing his design principles for the poor. Here are the first few. Does the Slingshot meet them?

  • The top need of people who are poor is to make money. The device should help someone make money on the local market.
  • People who are poor don't lack time and labor, so unless they can make money from the saved time and labor, they won't buy the device.
  • A device should pay for itself in "farm time" -- three to six months.
  • Successful devices address people's true needs rather than what "we" think "they" need.

Fisher adds that if a device won't make someone an immediate profit but will save money, it shouldn't sell for more than the cost of a chicken at the local market. A chicken, like this device, is an affordable, occasional luxury for poor families. But if the device costs more, only the middle class will buy it, and this group already has money for its basic needs [source: Fisher].

While Fisher's principles are reasonable for many product designs developed for poorer populations -- the LifeStraw certainly fits some of these criteria -- they don't seem applicable to the Slingshot in that it's a system that will provide for a large population, rather than an individual. And, while it's easy to agree with Fisher's statement that poor people need to make money, there's one caveat to consider; is it truly their "top" need? It's likely many would argue that access to clean drinking water demands top billing.

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