Japanese researchers have developed a technology to produce hydrogen from cattle dung and urine for use in fuel cells. The new technology developed by Junichi Takahashi at Obihiro Univ. of Agriculture and Veterinary Medicine and Sumitomo Corp.'s research group can also be applied to human waste and allows the production of hydrogen without producing unwanted carbon dioxide.

The research could also pave the way for the development of household "toilet generators,” according to the researchers.

In the process, cattle dung and urine are fermented under oxygen-free conditions to extract ammonia, which is then electrolyzed into hydrogen and nitrogen. The hydrogen is then fed into a fuel cell along with oxygen, where the two react to produce electricity.

Takahashi spent about $25,000 to build an experimental apparatus, which measures 2 m by 1 m, to produce hydrogen from fermented animal waste. Using the device in conjunction with a fuel cell, they successfully produced 0.2W of electricity from about 20 kg of cattle waste.

It’s estimated that, by increasing the power generation efficiency, six to eight tons of cattle waste, equivalent to the average amount of cattle waste produced each day at a cattle farm in Hokkaido, could produce enough hydrogen to generate electricity for an average household for 3 days.

In conventional fuel cells, hydrogen is currently extracted from utility gas, propane, heating oil or methanol through a process that creates CO2 as a byproduct. Taahashi’s technology produces no CO2, and the raw material is free.