Pure Genius: How Dean Kamen’s Invention Could Bring Clean Water To Millions

Jun 17, 2014

By Tom Foster

At first glance, the bright red shipping container that sits by the side of the road in a slum outside Johannesburg doesn’t look like something that could transform hundreds of lives. Two sliding doors open to reveal a small shop counter, behind which sit rows of canned food, toilet paper, cooking oil, and first-aid supplies. Solar panels on the roof power wireless Internet and a television, for the occasional soccer game. And two faucets dispense free purified drinking water to anyone who wants it.

Created primarily by Coca-Cola and Deka Research and Development, the New Hampshire company founded by inventor Dean Kamen, the container is meant to be a kind of “downtown in a box”: a web-connected bodega-cum-community center that can be dropped into underdeveloped villages all over the world. Coke calls it an Ekocenter. It’s a pithy name, but it masks the transformative technology hidden within the container.

Inside the big red box sits a smaller one, about the size of a dorm fridge, called a Slingshot. It was developed by Kamen, the mastermind behind dozens of medical-equipment inventions and, most famously, the Segway personal transportation device. Kamen is the closest thing to a modern-day Thomas Edison. He holds hundreds of patents, and his creations have improved countless lives. His current projects include a robotic prosthetic arm for DARPA and a Stirling engine that generates affordable electricity by using “anything that burns” for fuel. The Slingshot, more than 10 years in the making, could have a bigger impact than all of his other inventions combined.

Using a process called vapor compression distillation, a single Slingshot can purify more than 250,000 liters of water per year, enough to satisfy the needs of about 300 people. And it can do so with any water source—sewage, seawater, chemical waste—no matter how dirty.

For communities that lack clean water, the benefit is obvious, but to realize that potential, the Slingshot needs to reach them first. Which is where Coke comes in: The company is not just a soft-drink peddler; it is arguably the largest, most sophisticated distribution system in the world. That’s important because the scale of the water crisis the world faces is unprecedented.

Water seems so abundant it’s easy to forget how many people don’t have a clean source of it. According to the World Health Organization, nearly a billion people lack ready access to safe drinking water, and hundreds of thousands die every year as a result. Many more fall terribly ill.

Plenty of water-purification tools exist, of course—chlorine tablets, reverse-osmosis plants—but they all have drawbacks. Either they’re not adequately portable; they require replacement parts that can be hard to come by; or, most vexing of all, they remove only certain kinds of impurities, leaving others to poison the unwitting.

Kamen calls the global water crisis a “Goliath” of a problem, which suggests that he is David. He offers a quick refresher on biblical lore: David, it bears remembering, defeated Goliath with a slingshot.

n my life, nothing is ever simple or easy,” Kamen says. “I didn’t wake up one day and say, ‘Wow, there’s a global water problem. I think I’ll work on that.’ ” He’s sitting in his office in an old brick mill building by the Merrimack River in Manchester, New Hampshire. A life-size cardboard Darth Vader leans against one wall, and a wooden chair painted to resemble a seated Albert Einstein sits among a circle of leather swivel chairs. Photos of Kamen’s various helicopters (he’s had a number over the years and occasionally flies to Deka from his hilltop estate) hang on the wall while outtakes from his dad’s work as an illustrator for Mad Magazine and Tales from the Crypt decorate the hallway outside.

When we first sat down, I asked Kamen a simple question: How did you get interested in the water crisis? The answer turned into a highlights tour of his career, before he became famous or wealthy. Kamen is a natural storyteller, and his narrative unspools at high speed. Now 63, he grew up in Long Island, New York, and he ended up leaving college to start his first company, AutoSyringe, in 1976, to address a problem he’d heard about from his brother, a medical student: Certain patients needed such frequent treatment that trips to the hospital prevented them from living productive lives. Kamen’s solution was the world’s first wearable infusion pump, which administered doses of medication automatically. It was a hit, and Kamen sold AutoSyringe to Baxter International, a health-care company. He was just 30 years old.

Suddenly a millionaire, Kamen moved to Manchester and started Deka (derived from his first and last names). With a few exceptions, such as the now ubiquitous Segway, much of the company’s work has focused on medical innovations that solve lifestyle problems. One such project, begun 20-some years ago, was a machine to reinvent dialysis for patients with failing kidneys. Baxter International had built a device to do what’s called peritoneal dialysis, which involves filling the abdomen with a sterile saline solution and using the body’s own membranes to filter the blood. It’s less traumatic than hemodialysis, which requires passing blood through an external filter, but the contraption was noisy and bulky. The company asked Kamen to refine it.

Called HomeChoice, Kamen’s design was small enough to fit on patients’ nightstands and quiet enough that they could sleep while it worked. The machine required a lot of purified water, however—many gallons a day per patient—and that wasn’t cost-effective. Kamen’s instinct: Invent a medical-grade water purifier, so that patients could use water from their faucets as the base for their dialysis solution. He knew that existing purification systems, mostly based on filtration, weren’t exacting enough to meet his needs, so he looked to distillation. In Kamen’s eyes, distillation was magical in its simplicity. “The sun will evaporate the water out of an open latrine, and it will leave behind all of the bioburden, Cryptosporidium, and Giardia,” he says. “It will even separate the water from the arsenic and hexavalent chromium in a chemical waste site.”

As is so often the case, innovation, when it strikes, is an obvious-in-retrospect connection between seemingly disparate ideas. Kamen’s unique brand of genius is that he can recognize those connections and see their potential where others can’t.

But fitting one of the planet’s most elegant systems into a home appliance is not without its challenges. For his distillation machine to work, it would need to boil many gallons of water per hour, and that would require more energy than everything else in a typical U.S. home combined. So Kamen and his engineers exploited another basic scientific principle. To vaporize, water must get hot, and to do that, it absorbs energy. When the vapor condenses back into liquid, that energy gets released. If the team could recycle it, Kamen reasoned, they’d have a much more efficient process. They designed a “counterflow heat exchanger” that would run cool incoming liquid past superheated distilled water that had been vaporized and compressed. The difference in temperature would simultaneously cool the outgoing water and flash-boil the incoming liquid. All they would need is enough energy to get some water boiling and a little extra energy to power a compressor.

Kamen leans forward and grins as he ties the first chapter of his story together. “We said, ‘Wait, we can build a device that could take any input water, whether it’s got bioburden, organics, inorganics, chrome . . .and we can make pure water come out? We can put it in somebody’s house and make a supply of water for injection that would meet the U.S. Pharmacopeial standard, on less power than a handheld hair dryer, and we could make a thousand liters a day?’ ” Imagine how valuable that could be.

11 comments on “Pure Genius: How Dean Kamen’s Invention Could Bring Clean Water To Millions

  • @OP – “The sun will evaporate the water out of an open latrine, and it will leave behind all of the bioburden, Cryptosporidium, and Giardia,” he says. “It will even separate the water from the arsenic and hexavalent chromium in a chemical waste site.”

    Indeed! – Using a better grade of impure water Solar cookers (@ about $10 / £6 each) can be used to pasteurise it.

    (http://www.solarcookers.org/programs/safewater.html)

    http://en.wikipedia.org/wiki/Solar_Cookers_International



    Report abuse

  • When the vapor condenses back into liquid, that energy gets released. If the team could recycle it, Kamen reasoned, they’d have a much more efficient process. They designed a “counterflow heat exchanger” that would run cool incoming liquid past superheated distilled water that had been vaporized and compressed.

    This principle is used on rocket engines to prevent hot exhaust gases melting the engine structure, while at the same time pre-heating the fuel which is used as a coolant.

    The difference in temperature would simultaneously cool the outgoing water and flash-boil the incoming liquid. All they would need is enough energy to get some water boiling and a little extra energy to power a compressor.

    While this sounds good for treating extremely polluted water, the number of parts in the machinery, will make it very much more expensive than Solar Cookers which use simple reflectors to focus sunlight on containers of food or water.

    http://www.solarcookers.org/programs/images/safewater/safewater02.jpg



    Report abuse

  • @OP – “The sun will evaporate the water out of an open latrine, and it will leave behind all of the bioburden, Cryptosporidium, and Giardia,” he says. “It will even separate the water from the arsenic and hexavalent chromium in a chemical waste site.”

    Indeed! – Using a better grade of impure water Solar cookers (@ about $10 / £6 each) can be used to pasteurise it.

    http://www.solarcookers.org/programs/safewater.html

    http://en.wikipedia.org/wiki/Solar_Cookers_International



    Report abuse

  • Theoretically, if we scale up the Slingshot and use it on sewage and sea water on a grand scale, if it’s still energy efficient, humanity’s fresh water problem would be solved, right?



    Report abuse

  • This is brilliant! Clever of him to think of using Coca-Cola.
    For those who don’t know, Dean Kamen is known mostly (by normal people) for the Segway, but he’s mostly into medical tech. The Segway itself started life as a high-tech electric wheelchair that could balance on 2 wheels and climb stairs.



    Report abuse

  • You are completely missing the point. Your suggestion of solar cookers accomplishing the same thing is flawed. Kamen’s device is an enthalpy trick – and cannot be duplicated with a solar cooking system. Please research “latent heat of vaporization” as well as the influence of atmospheric pressure on the temperature at which water shall boil. You cannot duplicate Kamen’s process without the element of a compressor.

    Additionally – the sun isn’t always shining 24 hours a day – is it! (unless you are in the Arctic LOL)

    I’m the biggest fan of Kamen’s distiller. I can see this being a device installed in every person’s home in the future! (I want one!)



    Report abuse

  • @ Ken – You are completely missing the point. Your suggestion of solar cookers accomplishing the same thing is flawed. Kamen’s device is an enthalpy trick – and cannot be duplicated with a solar cooking system.

    “The same thing” is producing safe drinking water, which is a major problem in the third world. Solar cookers work on pasteurisation, and therefore do not involve “latent heat of vaporization”.

    My criticism is on the comparative cost of the much more complicated and elaborate device.

    Please research “latent heat of vaporization” as well as the influence of atmospheric pressure on the temperature at which water shall boil. You cannot duplicate Kamen’s process without the element of a compressor.

    A compressor and a complicated distillation mechanism, is what will make it many times more expensive, and in need of an external power source.

    I’m the biggest fan of Kamen’s distiller. I can see this being a device installed in every person’s home in the future! (I want one!)

    While the device certainly has merit in some circumstances, many people with “homes and power”, already have clean water supplies. It is the impoverished third-world which lacks clean drinking water and the money to acquire supplies.

    Kamen’s device, while useful, simply does not compete on cost with solar-cookers, in remote African villages or refugee camps.

    Additionally – the sun isn’t always shining 24 hours a day – is it! (unless you are in the Arctic LOL)

    Solar cookers have a proven track record in impoverished areas.
    (See the costs and links in the comments below.)



    Report abuse

  • I feel this is tending dangerously close to pseudo science. It’s not that this can’t work, it just requires a kW of power to produce half a liter of water a minute. Thus producing enough water for the billion people mentioned would require… A mere 300,000,000 such containers, power by a mere million clones of the largest solar power station on Earth. If we assume mass production reduces construction costs by a factor of 100, then the power stations alone will cost 22 TRILLION dollars! And that is where the pseudoscience comes in.

    The developing world simply does not have 300GW of spare electrical power lying around. It certainly doesn’t have 22 trillion. If it did, the problem would have been solve long ago. At BEST this is a niche product. At WORST it pulls money and resources from other more practical approaches.

    Popular Stupidity is entertainment – and should not be used as a reference for anything. Especially anything related to it’s key areas of ‘expertise’ of science and engineering. Any more than Fox News should be used as a reference for politics or current affairs. RichardDawkins.Net site really should know better.



    Report abuse

  • The analysis of Sir ANTIcarrot makes it sound like this method uses a lot of electricity.

    This link below shows the typical electrical costs in the USA of 1 Kilowatt Hour … and it is no more than $0.20 in most states.

    At 1/2 liter per minute, 1 hour of operation of this device will produce about 30 liters. If one is conservative and expects only 20 liters, that comes out to about one US cent per liter.

    http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_5_6_a

    At this time I typically purchase a 3L bottle of purified drinking water for about $1.00.

    The company who operates the equipment that produces my purified water has the advantage of economy of scale (large operation). The electrical costs of using reverse osmosis, water deionizers, UV treatment etc are certainly more than one US cent per liter … probably closer to 10 cents.

    Science also has a way of improving along the way, so if this device can soon be brought to supply clean drinking water to one million people, we will have learned a lot about doing it better for the next 999 million people.

    Lastly, most water purification systems used today have some item that needs to be replaced (cartridges, canisters, filters, etc.) Those all cost money and this system seems to do without them.



    Report abuse

Leave a Reply

View our comment policy.