Published on December 30th, 2009 | by Susan Kraemer17
Toilets That Separate Pee For Urea-Hydrogen Fuel Harvesting Already on Market
December 30th, 2009 by Susan Kraemer
Earlier this year, our sister blog: Gas 2.0 covered the use of using pee for fuel after a breakthrough at Ohio University published this summer in the Royal Society of Chemistry’s journal, Chemical Communications.
Ohio University researcher Gerardine Botte had developed a catalyst that could extract hydrogen fuel from urine much more cheaply than water.
The breakthrough was important because water is increasingly scarce in many regions, and will get even more so, the worse that climate change gets.
And that means that we won’t be able to spare water to make fuel. And that’s why a specialty new waterless toilet that separates liquids from solids might just be in your future.
Botte developed a cheap new nickel-based electrode that was able to selectively and efficiently oxidize urea to break apart the molecule to get hydrogen out. Not only was the electrode cheaper, but by using urea instead of water, she got twice the hydrogen at a third of the effort.
Only 0.37 volts were needed to strip urea’s four hydrogen atoms because they are not as tightly stuck together as the two hydrogen atoms in water. So: hydrogen fuel breakthrough.
But first urine needs to be separated. And harvested. And put on the market.
Here’s how that could happen. We would use toilets that don’t use water, a valuable resource. Instead we would separate out those valuable liquids from solid wastes. Sound implausible? As Gar Smith at Alternet describes this idea today:
“That is not such a strange idea: The human body is designed to send solid and liquid wastes in opposite directions. One immediate result of separating pee from poo is the elimination of the unpleasant aromas associated with the traditional outhouse.
While installing waterless toilets in high-rise apartments might raise certain engineering challenges, “urine-separating dry toilets” are being adopted around the world — from South Africa, Peru, Cuba, and India.”
That’s all very well for them, but what about for us in the US?
It turns out that a company called Natures Head has already developed a toilet that separates liquids and solids. While they had developed it to meet the hygiene needs of US boaters and RV-ers – their toilet has real application in pee harvesting, because it’s a dry toilet that separates liquids from solids, and composts the solid waste with the addition of peat moss.
They invented it because separating the liquids and solids helps boats and RVs not smell. The longer you let a composting toilet sit, the better it will smell when it’s time to empty it. That’s because the longer a composting toilet sits the more time it has to turn waste back into earth.
But it’s the urea that’s the real gold. Maybe that company should revamp its branding and marketing; spruce up the website a little to reach beyond the RV customer to the larger world. Because that humble little bucket of harvested pee in the front? You can pour that on the garden, because it makes great fertilizer.
Or you would store it in a larger bucket in the garage for routine kerbside recycling pickup to be recycled into the fuel of the future.
Image: Natures Head
Drive an electric car? Complete one of our short surveys for our next electric car report.
Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.