Heat your house or fuel your car with urine

It's a renewable resource, and approximately 10 billion litres are flushed away every single day around the world. But scientists say everyday urine should be conserved and used to heat buildings or even run cars.
If only we could find a way to harness it.
Gerardine Botte, an engineer at Ohio University, said in an interview with New Scientist magazine that harnessing the power of urine could mean that an office building of 200-300 people would produce about 2Kw of power.
“One cow can provide enough energy to supply hot water for 19 houses,” Botte told the New York Daily News in 2009. “Soldiers in the field could carry their own fuel.”
The key is from urea, which is the key ingredient in urine and forms roughly 2% of human urine. Each molecule of urea includes four hydrogen atoms - twice the number as in a water molecule. This makes it easier to process and an easier target for synthesizing hydrogen gas.
Hydrogen gas is the base fuel for most eco-friendly fuel cell technologies.
Botte believes hydrogen prices could drop as low as $1/kg, less than half the current valuation.
The idea isn't new. Ways to process urea using electrolysis or even microbial fuel cells have been described in various academic journals for years.
But in the latest issue of Energy and Environmental Science, Shanwen Tao from Heriot-Watt University in the U.K. describes how a fuel cell could work exclusively on urine, without any other energy input.
Just throw urine into the engine, and watch it go. No 'on' button required.
Tao hopes to market his idea by producing small portable sources of energy that could power radios or phones on the go, he told New Scientist.
"You could carry a small fuel cell for low-power mobile communications without having to carry the fuel," he said.

[Via CNews ]