correction about toilets

I wrote last month about the Gates Foundation’s competition to design a new toilet, and I mentioned that Eawag declined the chance to compete.  That was completely wrong.  Eawag did compete, and their design won the award for best user interface.  Congrats to team leader Tove Larsen.  I have to say, the schematic of their squat toilet looks a lot more likely to be accepted in parts of the world like southern Asia, where I have observed the ubiquity of squat toilets.  Their design also minimizes water throughput.

That said, the winning design from Caltech is impressive in other ways.  It is big and fancy and space-age.  It fits that the design was first produced for NASA.  But astronauts don’t make up the bulk of the population that needs access to toilets.  So it will be interesting to see who “wins” the implementation phase of the competition.

a lot of hype about s**t

The Gates Foundation funded a big research push among specially invited top universities and institutes around the world to “reinvent the toilet”.  The idea is that the toilet is as old as indoor plumbing, and we could surely use high-level technology to bring safe, sanitary toilets to the developing world, where water and wastewater treatment are hard to come by.  It’s a nice idea, and the Foundation does a good job of throwing money at problems to solve them rather than study them (see AIDS and malaria, for example).

It just so happens that a recent competition among the new toilet grant winners was won by a group from my alma mater, Caltech.  Their toilet uses

a photovoltaic panel to generate energy, stored in batteries, to power an electrostatic unit that purifies liquids drawn from a small septic tank. The unit produces hydrogen as it cleans the water, potentially a supplementary source of toilet power on cloudy days or at night. The unit also purifies the solid waste which can then be used as biofuel or fertilizer.

That’s great, and I’m glad for the breakthrough.

One teeny tiny criticism of the whole thing: will anyone in the developing world ever use something this fancy and complicated?  This is not meant as a patronizing comment, but rather a comment that reflects some of the serious issues on the ground when it comes to Western improvements of lives in the developing world.  My research institute in Switzerland, Eawag, has done a fair bit of research into human waste management in the developing world, including the dreaded (to engineers) social sciences of surveying people in impoverished communities, and came to a very different conclusion than the Gates Foundation: urine separation is key.  We therefore had urine-separating toilets installed throughout the institute.  I happen to know that Eawag declined the opportunity to bid on the Gates Foundation grant because the top researchers would have been forced to do something that their experience suggests would never work on the ground.  (One example of the relevance of social science in Bangladesh: some local people prefer the metallic taste of groundwater that happens to be high in arsenic.  Non-metallic taste is associated with the local surface water, which is visibly contaminated with bacteria.  So some refuse to drink from safer groundwater wells that lack the geochemistry to have the metallic taste. That’s not engineering, that’s psychology.)

The Gates Foundation is doing a good thing, don’t get me wrong.  Who knows, maybe this technology will start turning up in the US as well.  But I worry that by involving researchers based on their school’s credentials, rather than their experience in this field, which is brand new to them, will lead to a lot of whiz-bang engineering feats that won’t translate well on the ground.  Well, it could be that Gates has the money to spare…