One of Asia's biggest landfill gas recycling projects will be able to supply power to 100,000 households a year without any waste water or pollution.

The Shanghai Laogang Renewable Energy Co opened in Nanhui District on Wednesday, Xinmin Evening News said.

The company will use methane gas and carbon dioxide from garbage to generate power to serve the national grid and local homes and businesses by the end of the year.

The company will be able to handle about 8,000 tons, or 70 percent of the city's garbage annually in the near future, and will be able to generate up to 110 million kilowatt-hours of electricity every year.

Methane gas and carbon dioxide are greenhouse gases produced when waste decomposes. Methane gas is a clean form of energy. One cubic meter of methane gas can produce 1.5 kilowatt-hours of electricity.

Laogang's garbage dump could produce 81 million cubic meters of landfill gas every year, said the company.

If the gases are not properly handled, explosions or fires could occur.

However, burning landfill gases to produce electricity rather than allowing them to disperse naturally is considered the best way to protect the environment.

After a preliminary process, most of the landfill gas will be sent to generators to produce electricity. Extra gas can fuel boilers.

(Shanghai Daily July 24, 2008)