Kyoto City Generates Electricity from Household Waste

Kyoto City in Japan announced on January 25, 2007 that it had achieved Japan's first successful series of empirical trials producing hydrogen from biomass, such as food waste and used cooking oil, for use in fuel cells that produce electricity. One ton of household waste generated 250 kWh of electricity, equivalent to one day of power consumption by 25 households.

In collaboration with Kyoto University, the Ministry of the Environment and the Biogas Study Group, Kyoto City started the research and experiments in 2005. A range of empirical trials are collecting biogas fermented from waste glycerin, etc. that is produced in fermentation tanks that convert food waste and used cooking oil into biofuel. After impurities are removed, this biogas is then converted into hydrogen that is used by fuel cells to produce electricity.

These empirical trials have revealed that a stable supply of electricity is possible even when household waste is roughly separated and includes some plastics. To produce biogas efficiently, a certain ratio of paper is needed in the waste. Diapers that have come increasingly into use for elderly people can be treated to produce biogas efficiently by removing the plastic film from the surface of the diaper. It was also confirmed that the addition of waste glycerin to food waste results in more stable and efficient electricity generation.

The city plans to build a biogas plant (60 ton/day) in its South Clean Center, presently undergoing re-construction. It aims to start operating the plant in 2013.

http://www.city.kyoto.jp/koho/eng/plan/warming.html

Posted: 2007/07/29 10:14:53 AM
Japanese version