A $100,000 grant from the Bill and Melinda Gates Foundation has been made for turning human excrement and urine into methane gas, heat and electricity. Similar technology already exists, but the Calgary researchers said it has not been used in an integrated way. Actually, NASA showed an interest in converting human waste into electricity at least seven years ago due to an estimate that a two-year trip to Mars would generate about six tons of human waste, and the current practice is to ship it back to Earth. They discovered that the bacteria family Geobacter have the ability to consume organic waste and transfer electrons into metal, meaning they might be used to generate electricity. NASA was investigating the use of waste, the bacteria, and a new type of fuel cell. As much as fifty percent of the energy in excrement is carried over from when it was food. It sounds like the Canadian researchers are more focused on making a biodigester which digests organic matter to create methane gas that can be burned to make electricity.
This type of biodigester was being built a year ago in a New York town. Converting to electricity would obviously be another source of power, but it would also help reduce their costs for dealing with solid waste.
Another form of such conversion is the Loowatt, which uses waterless toilets to collect human waste in order to store it temporarily, before transfer to a biogas unit does the conversion to methane gas. Loowatt has some cute cartoons depicting this new energy cycle. Human culture generates a gigantic amount of bio waste that is not used for much that is beneficial. For example, each year in San Antonio about 140,000 tons of biosolids are created. That is enough to fill 1,250 tanker trucks per day with natural gas. By using a vendor they could collect and convert their biosolids and then sell gas for about $250,000 per year.
Image Credit: Jean-Paul Grandmot