November 21, 2012

10 Ways to Put Human Waste to Use

It was hard to limit the list to just ten. With a mix of proven technologies, award- winning prototypes and an eye-catching entry at Maker Faire Africa this year, we present ten ways to put poop and pee to good use.

Urine-powered generator

Four young Nigerian women ages 14 and 15 made interesting headlines when they debuted their urine-powered generator at Maker Faire Africa in Lagos this month. The device uses electrolysis to separate hydrogen from the water in urine and then fuels a generator with the gas. Water might work just as well, but saying your phone charged on urine just makes more of a splash, so to speak.

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Sridevi Govindaraj tours a banana plantation, one of the crops that she tested with human urine as a fertilizer. Photo courtesy of Sridevi Govindaraj

Fertilizer

If 40 percent of the people in India stored their urine to use it on their crops, the country’s farmers could save $26.7 million (1.2 billion rupees) in fertilizer expenses, Sridevi Govindaraj calculated when she completed her doctoral thesis in ecological sanitation at the University of Agricultural Sciences in Bangalore. Incidentally, she may be the only person in India with a doctorate in ecological sanitation.

Our bodies make about four to eight cups (one to two liters) of urine per day, and it’s rich in nitrogen, potassium and phosphorus, the same elements that crops love. It’s also pretty cheap to make. Urine, Sridevi told E4C, is a useful resource.

Resources

E4C news:Urine is fertilizing crops and saving money in India
Appropedia: Liquid fertiliser system

Photo courtesy of NASA

Drink it

NASA is developing a complex, expensive and, as it turns out, somewhat buggy machine that purifies human urine to recycle the water for astronauts to drink. Rex Walheim, a NASA mission specialist, tests the Forward Osmosis Pump Syringe in the photo, injecting a colored “Challenge Liquid” into the Forward Osmosis Bag on the middeck of the Atlantis.

It may be much easier to purify urine for drinking here on the ground, however. We’ve heard of the theory that drinking urine has health benefits, and fresh urine can be sanitary (although it could pick up pathogens on its way out of the body if the person has a disease). But for the select few who are trapped in a desert with no water and can’t stomach the thought of drinking straight urine with no chaser, we suggest making a solar still. The still uses the sun’s radiation to evaporate water from the urine, collecting the condensate on a surface, such as plastic wrap, and channeling it into a container to drink.

Resources

YouTube: How to make a solar water distiller
E4C Solutions Library: Solar Water Distiller

Photo by Thomas Shahan / Flickr

Animal feed

Black soldier fly larvae thrive in feces, and after processing, they make for nutritious farm animal and fish feed, and also biodiesel. A research team at the London School of Hygiene and Tropical Medicine is looking into how to raise them in central facilities on a diet of waste collected from latrines. An earlier, alternate version of the plan is a fly-catching latrine that lures the pests in but prevents their escape, turning the latrines into fly killers and possibly even larvae producers.

Field tests are underway now in Cape Town, South Africa.

Resources

Sanitation Ventures: Black soldier fly additives
Sanitation Ventures newsletter: Toilets and fly larvae project, pg. 13

Simple, effective toilet designs like this one, the CRAPPER, are more likely than more expensive devices to become the “toilet of the future” that serves the developing world, Jason Kass says. Photo courtesy of Jason Kass

Compost

Composting latrines turn a sanitation problem in an agricultural solution. In fact, Jason Kass, founder of Toilets for People, recently called a variant of a composting latrine the “toilet of the future,” in a guest column for E4C.

The basic ecological composting latrine design is two pits, one covered with a semi- mobile structure that is the actual toilet and walls. You mix the human waste with materials such as ash and yard clippings or agricultural waste. When the pit is full, you move the structure to the second pit, cover the first and let natural bacteria and the animal agents of decomposition do their work. When the waste is naturally processed, dig up the compost and spread it as a safe fertilizer on crop fields.

Variations of the design collect the waste in removable drums for off-site composting. Toilets for People and SOIL are two organizations promoting this method in Haiti.

Resources

E4C news: High-tech toilets? What we need is a low-tech toilet revolution
Five questions with Sasha Kramer (SOIL)

E4C Solutions Library: Ecological Sanitation Latrine
Compost Toilets in Waterlogged Areas

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A bolete mushroom. Photo by Vicki & Chuck Rogers / Flickr

Grow mushrooms or watercress

Rural Bolivia has a toilet shortage. Fewer than half of rural Bolivians have regular access to a toilet, according to the World Health Organization. But with such scarcity, by definition toilets are strange, foreign objects, and many people there are not inclined to try them out. Aid organizations have given away composting latrines to communities in the region, but studies show that only one-fifth to half of them are used correctly. Instead, people defecate on the open ground. To entice better use of the free toilets, Water for People is experimenting with a composting business venture. Compost from correctly used latrines is spread on reforested land planted with Monterrey pine saplings. The pine trees provide a habitat for expensive bolete mushrooms, which can generate relatively high incomes for the communities.

We see evidence of some creative problem solving in that experiment, but the general concept of cashing in on compost is not unique to Water for People. SOIL and other organizations, some mentioned here and elsewhere on E4C, are also turning poop into profit with some encouraging results.

Not to leave out number two, an example of the fertilization powers of urine is an odd experiment in raising watercress. A Web page that is enthusiastically named drinkpeedrinkpeedrinkpee offers a kit and a how-to guide to growing (supposedly) edible watercress in a bowl full of urine.

Resources

E4C news: Toilets for mushrooms: An experiment to improve sanitation
Submersible Design: Urine fertilizer watercress DIY kit

Biogas production

One of the gases that lends human waste its stench is methane, which, as 13-year-old boys with matches worldwide must know, burns. A biogas digester collects methane as microbes produce it inside a closed container (oxygen can be deadly to microscopic methane-producers). With the right equipment, gas channeled from a container of waste could generate electricity, heat water for homes and industry and cook food on a gas range. Sanergy, the organization behind the useful bicycle modification that converts it into a latrine pump, also promotes biogas production from waste collected from urban communities in developing countries.

Resources

E4C news: A bike-powered poop pump is redefining low-cost sanitation
E4C Solutions Library: Biogas Pit Latrine
Biogas Cooking, Nepal
Domestic biogas plant, China

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The Caltech team poses around their hydrogen-gas producing toilet design. Photo courtesy of Caltech

Hydrogen gas production

Michael Hoffmann’s Gates Foundation award-winning toilet prototype uses solar power to break human waste into hydrogen gas and leftover solids. Hoffman and his team at Caltech showed how the toilet could store hydrogen in fuel cells as an energy source. The toilet treats waste on the spot and syphons off hydrogen for later use as energy.

Generate power on the spot

In a unique variation of biogas production from human waste, researchers at Delft University of Technology have worked out a way to produce synthetic gas – “syngas” – which is a mixture of carbon monoxide and hydrogen. Their Gates Foundation award- winning design dries the waste on the spot and zaps it with microwaves to heat it into a plasma for gasification (all proprietary technology). Then the toilet stores the gas in a solid state fuel cell stack to produce electricity.

The design is affordable, the researchers say. Like other prototypes on this list, we mention this as a point of interest while we’re waiting to see if the end products are also practical. No photo is available.

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Debunked: Do not treat this sting with urine. Photo by Keithius / Flickr

Treat jellyfish stings

False. It turns out that urinating on a jellyfish sting will do little to alleviate the burn and could actually exacerbate it. Thanks to Scientific American, About.com and other sources for this important expose. This new information raises a question, though: If it doesn’t work, then who spread this rumor to begin with?

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Image courtesy of RTI International

Burn it as fuel briquettes and biochar

With the last use debunked, we’d like add a final use for human waste: Fuel briquettes. Not compost, not biogas or hydrogen fuel cells, but actual, burnable fuel made from treated human waste. Researchers from the University of Colorado in Boulder won a Gates Foundation grant to develop a solar-powered toilet that turns waste into biochar.

And researchers from RTI International in North Carolina won a Gates Foundation grant for their toilet design that converts waste into fuel briquettes that it burns for storable energy. It also churns out treated, but non-potable, water.

We came across other uses for human waste: Urine has been used as a disinfectant, invisible ink and dye for cloth, and both urine and feces are necessary to diagnose certain illnesses and parasitic infections, for example. If you have other tips on how to put waste to use, please share in the comments below.

Comments from the Community

34 Comments

  1. K.p. Singh says:

    NICE

  2. Rhys lloyd says:

    super cool! learned alot from this! make sure to pass it on!

  3. Julie Christian says:

    Awesome Ideas. Im very interested in human waste to methane gas conversion.

  4. CHRIS GOWELO says:

    I can do my own electricity

  5. hilary clinton says:

    this information is very useful :):):):)

  6. Mike jiya says:

    I want to have electricity at home using toilet

  7. fiona says:

    what do you mean by ‘treated’ human waste i.e urine and faeces to make fuel briquettes.
    Is this necessary if the product is to be burnt? thx

  8. Penjem says:

    There are good ideas, Am greatful. Can there be videos of the explanations above.

  9. rachit says:

    thats too much nice n i also want 2 work on it

  10. joe says:

    the BURNING OF HUMAN WASTE HAS INTRIGUED ME. IF THE ENERGY dissipated as heat can be harnessed to do some work then the system would be even greater.

  11. fanna garra says:

    simple steps on converting human waste to methane gas

  12. mahesh says:

    from many days I was thinking of humane waste transform into gas ,as fertilizer ,etc . we can get free energy also ,what if we take a big step to get energy from human waste ,instead of using coal .
    because of this we will not pollute our rivers , it will help I many ways but we have to do more research on it.

  13. poop says:

    you can use it to keep your toilet from flushing.lol

  14. toilet problems says:

    Hi, I do consent your ideasyou’ve present on this post. Toilet problems are always nasty but you have to do, also the repair payment is not cheap. Sometimes I prefer to do the job by myself. Do you still have any other posts about this content?

  15. Ryan says:

    you can also use urine to make saltpeter for use in gunpowder

  16. indrajeet mandal says:

    Its a fantastic & motivating debate shown ,how to utilize a ‘waste’ into a usable sustenance of adaptation.
    So, where the PROBLEM exists…? Human Defecates provides Food-Ingredients to Insects like Ants/Bees/Birds/C’roches /Grasshoppers/Bugs/Fish/Dogs/Jackals etc…etc… It acts as Compost/Manure after rains when it enriches the Soil. Its smell spreads habitat and gives the status of a surrounding. It’s Just Adaptation only… The GOD has created every factor of existence as upon its needs and deeds.
    If it is ‘Force-Stopped’, Human Habitations will get infected and attracted by unwilling virus/bacteria that get their footing from open Wastes. So, Motivating the population is good but it shouldn’t be highlighted as an act-of-embarrassment.
    – Mr.IM/ETL-KOL. 9432096923 / 08617744776.

  17. bILL nUNNEH says:

    STILL WORKING ON A PROJECT FOR A COMMUNITY OF ABOUT 8000 PEOPLE TO USE A SINGLE WASTE DISPOSE….

  18. Eric Sandoval says:

    These and many other inventions can change the world. If even a fraction were used , it could greatly improve our world. What if you scaled bACK ? uSE EVERY AND AND ALL GREEN INVENTION? DESIGN AND BUILD A GREEN COMMUNITY. EVERYTHING FROM THE GROUND UP! FRESH WATER GENERATION AND STORAGE, RENEWABLE ENERGY, ENERGY SAVING DESIGNED HOMES, COMMUNITY GROWING, COMMUNITY MAINTENANCE AND ENVIRONMENT SMART.

    tHE COMMUNITY INVESTS IN THE DESIGN AND BUILDING, AIDED BY GRANTS FOR SCIENTIFIC RESEARCH!

    cHEW ON IT!

  19. Kwabi Abel Oppong says:

    All these are nice and innovative ways to make life easier.But we must consider the environmental problems it’ll pose and how to curb them…..Thank you

  20. MUKul mani singh says:

    Wastage should be used fully and should be recycled and used. We use our less valuable things first and after that we use our more valuable things. We save our more valuable things. Wastage are lesser valuable and so it is used totally. It is found free and daily. If we use them we will save our valuable fuel etc. Government should do work for that

  21. MUKul mani singh says:

    Plants of cleaning dirty water should be mounted in drainage systems and after filtration the filtered water should be left in rivers. The extracted

  22. we enjoy what you guys have posted here. dont stop the super work!

  23. LIVINGSTONE LOHIA says:

    I very highly appreciate this method of using human waste and turning into something useful. I think it must be applied in India very specially in villages where people go out in the fields for sanitation and pollute the land. I wish toilets are made in villages where all the villagers could go for peeing and pooping in a clean toilet , a good way of collecting human waste. Then produce something useful out of waste. I think it is a brilliant idea. I don’t care what others who criticize this they think. Someday I would like to adopt this idea. By the way I very highly appreciate and encourage Sridevi Govindaraj for coming up this technique. I support her a lot. Indian rural areas desperately need to adopt this technique and make the country cleaner and better.

  24. hi would really appreciate your kind assistance to do the same in my country Kenya. kindly contact me on email Zippyrudisha9@gmail.com or cell no +254728805554.waiting to hear from you soon.regards

  25. Luke Mendes says:

    Nice article. What i like is the Bio toilet that burns the waste and treats the water. The one with the solar panel etc the last image by RTI international.
    I would love to Pilot test this in INdia in some tribal areas.
    Do let em know how i can get more info on it. Im sure it can get a bit more frugal in that design.
    Thanks for the info.

  26. Mahesh Bende says:

    Nice Information.

  27. Sharon Ellis says:

    I know, the world needs to conserve fresh water. These, new alternative methods are bridging gaps in the conventional idealism. The night soil needs to be addressed in the day time.

  28. pairote leetavorn says:

    At 73+, I have been studying, survey, & researching how to get a community, town or city to be self-sufficient in their food, energy, etc. & trying to get an example of my ‘ Dream Project ‘ of ‘ GREEN @ ECO SUSTAINABLE SOCIETY ‘ into Public, especially, those who are poor & needy ……
    I shall try to launch it within 2018 & if it is successful, the poor & needy in every country could have a much & much livelihood of better living & Be Happy.

    Pairote Leetavorn (from ‘ The Land of Smiles ‘, Thailand)

  29. Douglas says:

    insightful, we have a waste problem in Nigeria, and i am pioneering an independent research to solve it. Sewage is directly dumped in rivers, lakes and other gradual moving waters, sometimes canal.

    What advice can you give me.

    My country is Nigeria.

  30. mfransen@ziggo.nl says:

    Using human faeces or animal manure as fertilizer is devastating for health, soil, plants and the water! This is a black market I don’t support at all! The world is in need for a global dung ban.

  31. mfransen@ziggo.nl says:

    Power to the poop: let’s use human waste to run vehicles or as a cooking fire!

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