This system packs the poop in a biodegradable film, all part of a toilet as service system.
Pee and poop have been a bit of a TreeHugger obsession over the years, as we look at alternatives to the standard toilet which is so wasteful of water and the useful stuff in pee (phosphorus) and poop (fertilizer). I thought that we had covered every new toilet tech on TreeHugger, but we missed the Loowatt, developed by Virginia Gardiner when she was at the Royal College of Art in London. She founded Loowatt in 2010 and got a Gates grant in the Reinventing the Toilet Challenge (which I crapped on here).
It’s an interesting design that encapsulates each poop in a biodegradable film so that it isn’t messy and doesn’t smell. In Madagascar it is being used as a “toilet service” where the deposits are picked up and taken to an anaerobic digester to produce methane and clean fertilizer. As we have noted many times, a toilet is a trivial invention; it’s the system. Loowatt says the same thing: “All toilets depend upon systems: servicing, processing, inputs and outputs.”
Loowatt has developed models to calculate system outputs and their potential value to reflect where the system is installed. Considerations include number of users, types of waste, and energy applications. Alongside this model, we are developing our methodology for system and value optimization.
I learned about the Loowatt from a fascinating article Reinventing the Toilet, published in Mosaic, a site published in the UK by the Wellcome Trust. Lina Zeldovich followed the Loowatt to Madagascar and describes the problems in the developing world, including those of building a water-based system like we are used to.
In many places building a flushing toilet system, as we know it, is nearly impossible. Some places simply don’t have enough water. Some have too much, which complicates water treatment processes because of floods and overflows. Others don’t have the means to build the water-based infrastructure.
But she gets why it is so important for everyone to look at alternatives:
…sanitation experts think that in the era of climate change, when droughts and floods are becoming increasingly common, the West may have something to learn from the little waterless loos piloted in penniless Madagascan neighbourhoods. With the world’s population ever-increasing, places that historically relied on water for sanitation may have to reconsider how they flush.
Lina Zeldovich talks to David Waltner-Toews, author of The Origin of Feces, who explains why our current system needs to be fixed.
Treatment plants rely on a steady supply of water, which is not universal. The plants don’t recover enough nutrients from the sludge, so leftover phosphorus and nitrogen trickles into the water, helping to cause algal blooms. The ‘downstream’ solution just doesn’t work on a crowded planet, Waltner-Toews says. “In the 21st century, everybody is downstream from somebody else.”
Waltner-Toews links our international food distribution system, where we are shipping strawberries and tomatoes all over the world, to our waste of valuable nutrients in poop and pee, and calls for a “redistribution of nutrients on the planet.”
“You’re taking all this biodiversity out of one ecosystem and creating these piles of shit somewhere else,” Waltner-Toews says. And because we don’t ship our poo back to where the food came from, we deplete soils in some places and over-enrich others. So if we’re trying to make growing and eating food a local issue, then why not our poo processing too?
Loowatt shows this cute cartoon of a guy using his Loowatt, taking his poop roller suitcase to the local digester, then picking up some local food, no doubt fertilized by the digester residue, cooked on local biogas, It's all a closed loop. I wonder if people would be willing to do this. Because there is no question, something has to change.