Sapporo City in Hokkaido will utilize heat pump technology to recover heat from warm, treated wastewater from a sewage disposal plant in Nishi Ward. The treated wastewater presently flows into a ditch constructed to melt and carry off snow, the Kotoni ditch. The system will heat two public facilities -- the Nishi Ward Citizens' Center and the Nishi Ward Health Center -- in the winter of fiscal 2007.

Several snow-melt ditches have been constructed along major arteries in the city to dispose of winter snow accumulations. Warm water pumped from the sewage plant melts the snow dumped into these ditches. The treated sewage water is warm - about 13 to 14 degrees Celsius - even during winter.

The planned system will use heat pumps to collect the heat equivalent of up to about three degrees Celsius from the wastewater to heat water in a circulating heating system up to around 50 degrees Celsius. By switching from city gas to the new system, the two centers are expected to reduce their heating costs by 25 percent, or about two million yen (U.S.$ 1.71 million) per year, while cutting carbon dioxide emissions also by 25 percent.

http://www.city.sapporo.jp/city/english/

Posted: 2006/05/25 10:07:41 PM
Japanese version

TAG Energy , Global warming , Local government , Material reduction