In a joint research project with the Tokyo Electric Power Company (TEPCO), the Bureau of Sewerage of the Tokyo Metropolitan Government has been developing a micro hydro power generator that uses a slight head drop when releasing treated sewage effluent into a river at the Kasai Treatment Plant in Tokyo.

With a head drop of less than 5.05 meters per second and a water volume of 0.68 cubic meters, the generator can yield an output of 27 kilowatts, which is enough electricity for 60 households a day.

One kilowatt of hydroelectricity can reduce 0.384 kilograms of carbon dioxide emissions. The reduction in annual CO2 emissions attributed to the Kasai Treatment Plant would therefore amount to some 77 tonnes, equivalent to the CO2 volume absorbed in a 21-hectare forest.

To save energy, the bureau has been generating electricity using biomass and also using discharged heat for power generation, air-conditioning and heating in local areas. Based on TEPCO's proposal to use cost-efficient technology, the bureau began the research on micro hydro power generation at the Kasai Treatment Plant in March 2001.

Currently, the bureau and TEPCO are developing a stable power generation system unaffected by tides and sewage volumes. This joint research project is due to end in 2003, and the bureau will then consider introducing the system for other sewage plants in the Tokyo metropolitan area.



Posted: 2003/05/16 10:26:54 AM
Japanese version

TAG Energy , Food/Water , Global warming , Local government , Non-manufacturing industry