The Gates-Funded Toilet Of The Future

After an extensive search, the Gates Foundation has given millions to this futuristic power-generating toilet from Caltech—with the hope that it can be the solution to sanitation problems around the world.

Today is World Toilet Day. That’s not as silly as it sounds. Two and a half billion people around the world don’t have access to clean toilets, which means they are at risk for a number of diseases—diarrhoeal diseases, in fact, kill someone every 20 seconds. More people die from poor sanitation than measles, malaria, and HIV/AIDS combined.

There is some hope. The Bill and Melinda Gates Foundation has been steadily offering grants to sanitation initiatives, including some focused on creating better toilets for the developing world. Caltech won the Gates Foundation’s Reinvent the Toilet Challenge (a call to create cheap, safe, and hygienic waterless toilets) with a solar-powered, self-cleaning toilet that converts urine and waste into hydrogen and fertilizer.

The seeds of Caltech’s toilet design were planted 17 years ago when Caltech engineer (and toilet team leader) Michael Hoffmann patented a design for "multilayered nanostructures doing electrochemical degradation," according to team member Asghar Aryanfar. "He was looking for any kind of application until Bill Gates announced the competition," says Aryanfar.

The toilet features a solar panel that powers an electrochemical reactor, which in turn breaks down waste into sanitized solids (a useful fertilizer) and hydrogen that can be stored in fuel cells to power the reactor on cloudy days. A pump sends treated water to a reservoir on the top of the toilet, where it can be used for irrigation or other purposes.

Aside from the electrodes, which have an estimated lifetime of a decade, all the mechanical parts in the toilet are easily reparable—a key feature in remote areas. "Making the comprehensive prototype is a little challenging. We’re looking at different shipping containers so we can ship easily," says Aryanfar. "The good thing is we know the technology works. What remains is the prototyping."

Caltech’s solar toilet team now has $1.6 million in funding from the Gates Foundation; they expect to have a prototype ready to ship to Africa—with a price tag of approximately $2,200—by December 2013.

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  • David

    A stupid idea from the Gates Foundation. Sun-Mar, a Canadian company, already makes a very good composting toilet. The Gates Foundation would have done better by giving Sun-Mar the money for a third world lower cost redesign. Sun-Mar's toilets cost about a 1000, so they already beat the Gates crapper.

  • Kuma

    It seems that someone "feels" that
    they have been in the poor community, but actually they DON'T.

    ->Someone says, “the US$ 2,200 toilet will serve
    one village for a decade". For example one village is 500 House Hold each
    with approximately 5 members. So it is about 2500 people. No, let's make it smaller: 100HH each with 5 members with
    total of 500 people. Biological hour of human is similar each other (read
    "body detoxification cycle"), so within a few hour the US$ 2,200
    toilet must serve at least 300-400 people. How can it possible?

    ->Someone says, "It will help to prevent the
    disease/medification". Please see the bottom line, from economical aspect.
    For example thermophilic composting which more economical will provide much more unit. It will help way more people, way more beneficiary and impact.
    ->And in the aspect of energy balance, the waste should produce energy rather than consuming more energy. Those solar PV perhaps also needs battery, if not then someone which "poop" in the night won't get any "service". And battery are costly, usually replace within 5 years, etc.

    -> Last but not least, have you ever experience a Hydrogen Explosion? I'm sure you did when in Chemical experiment in High School. But let's imagine in a bigger scale, in a dense population (poor-area). I can't imagine...
    Hydrogen System require a very expensive system, just to make sure it's safety. If I have an option, I will never want to be near this thing. I was working with Hydrogen for diesel-fuel combustion research.

    +Seems amazing, high tech -> shining
    -Very expensive.
    -Way less impact and beneficiary.
    -Too much consuming energy
    -Very dangerous w/ the Hydrogen risk in dense population

    This prototype is actually already died pematurely in the planning process... sorry to say. unless if you want to make people in danger...

  • gatto blanco

    Maybe it comes with Windows and a screen to watch with.
    Really who in their right mind is going to fund this when a septic system like is still a viable choice for a single family house is so cheap.
    These people need water first ............ no, they need to learn that they need to come into the 21 Century and get over the past.
    Their real problem is something that we talk about but don't suffer from too much, big government and big religion.
    Maybe we should look around at ourselves and say why are they not wanting to be like us??

  • Bhaffie

    HAHAHAHAH ... best part is when they show a political map of the world, color a bunch of contries blue, and label them "Developing Countries"

  • Guest

     yeah, really - half those countries aren't even developing countries, and then half the real developing countries aren't even highlighted.  Did they just ask a bunch of 4th graders to make them a map or something?

  • George D

        I used to work for a company that was full of civil engineers who set up sewage and water treatment plants.   Communities all over the world hire them.  This is what they do and it works!

  • George D

    I used to live in a community that took its potable water from the River Rasin.   Several cities also took their water from that river.   Each city dumped its waste water from the sewage treatment plants after treatment back into the river along the way.   Solids were collected, dried and bagged as fertilizer.   Methane from the plant provided most of the energy for drying the solids.   Settling tanks in the water input side and output side treated the water to make it safe.   To this very day the system has worked without flaw.   However, it requires permits be required to discharge, build, or set up a toilet or water system.   Africans do not believe in community laws in many cases.  This is the case in many third world nations.  Many of the neo cons today try to express the same lack of common safety and organized efforts by communities as a good thing.   It is not.   Our system was built on decades of disease and mass illnesses killing of millions.   Public health is a key to our civilization.   No nation will survive without it for long.   China is learning this lesson as we speak.

  • Haris M.

    You know, people in Africa enduring poverty are smarter than computer users of developed world, who would REFUSE to pay for a literally overpriced craptaker. Gates has switched from making overpriced Windows to overpriced Toilet, but he is essentially still doing what he does best.

  • Marksciscenti

    Um... GatesTechBoy is more interested in a high tech gadget that masks as simple and low tech just to get everyone smiling at him.

    I don't think that high tech in 80% of the world - that can't produce, let alone pay for such things is quite silly and an astonishingly stupid idea - yes, yes, "it's a prototype". So the ... what? It is still made with unrenewable and unsustainable resources!

    And using the by-products of the waste to fuel the electrochemical reactor, to breakdown more waste, is just, well, astonishingly stupid! What a waste of energy!

    Many have already said it, and I will say it again in another way. Composting toilets... There are many many very simple and straight forward plans that are waaaayyy easier then the also high tech ones out there.

    It is called Thermophilic composting. If built right (with natural materials already handy to most of the worlds populace) ALL of the human waste mixed with the correct ratio of organic carbon materials WILL reach sustained temperatures of 150 degrees fahrenheit/(100 C - ?). All pathogens get killed. This then degrades into Mesophilic composting and when left for two years what is left is clean composted fertilizer. That can then be used to, um... fertilize degraded land, to produce food - get it?

    There is plenty of science behind this. Thermophilic (high-temperature) composting is well known to destroy many seeds and nearly all types of pathogens. The sanitizing qualities of thermophilic composting are desirable where there is a high likelihood of pathogens, such as with any animal manure, (humans are animals you know...). Applications include humanure composting or deep litter technique.

    Ah, I can just hear the collective cries of the fecalphobes in the Western countries, the so called "developed world".

    What exactly is "developed" when most of our fresh potable (drinkable) water is used to flush human waste???

    Joseph Jenkins, the author and promoter of the Humanure Handbook (who's been doing this type of composting for over 40 years), submitted and application to this "so-called competition" and was deflected, turned away, never received a reply. You know why? It was not high tech. His plan was large scale and included the use of the waste of a large city in the Eastern US.

    Go figure...

  • Karley

     Hear, hear!  Thank you for bringing up the Humanure Handbook!  We use his system, and it is aptly named, as we do indeed love our Lovable Loo!  But it's just way too simple, inexpensive, and immediately scalable to the developing world to be considered by the likes of the Gates Foundation.

  • Jason Kass

    Cudos to the Gates foundation for bringing more attention to the sanitation crisis, but the high tech, high price tag approach needs to be corrected. Here's an idea from Engineering for Change for how to turn things around and get one third of the world's population a functional toilet: https://www.engineeringforchan...

  • Raysue1

    Interesting.  We would still be using our most precious resource, water.  There are currently composting toilets and greywater systems that could totally recycle our water and waste for landscaping use that could produce oxygen and food for the same dollars. We could pay for the systems through our water and sewer bill savings. . .but that would be illegal.

  • Lee1991

    Also note, this thing was the winning entry. Makes you wonder what the losers looked like.

  • Nil

    This toilet is ancient. Where are the heated seat, automatic lid closing, auto flashing, warm air dryer, and warm water cleansing?

  • Andy Parrott

    It seems to me that much like Windows this thing is vastly over engineered and overly expensive. 

    What is wrong with a composting toilet, if the ground is below the water table, then a tank in needed, but apart from that it's easily sustainable with minimal maintenance and no power requirement??? What is the carbon footprint for all of this electronic rubbish? It creates the compost more quickly but will cost the planet dearly in terms of resources wasted.

    Send a septic tank out or a liner for a composter and it should keep people going for decades.