1) Biogas generated in sewage treatment process in Hong Kong
Biogas from digesters in the sewage treatment works in Sha Tin, Tai Po, Fan Ling, Yuen Long have been utilized for a number of purposes - in boilers for producing hot water for the digesters, in engine-driven blowers to provide compressed air for the sewage treatment process, and in engine-driven electric generators to provide electricity for the sewage treatment works.
An example is the 330 kW engine-driven electric generator in Shek Wu Hui Sewage Treatment Works, commissioned in 2006.
2) Overseas example - SBI Friesland in the Netherlands
The plant is one of the largest waste processing installations in the Netherlands, with a capacity of 230,000 metric tons per year. The plant reclaims paper, plastic, metal, stone, glass, sand, and organic material from residue waste. Biogas is extracted from the organic material to produce electricity and heat. Some 60 percent of household and industrial waste is reused. The remainder is sent to incineration plants or landfills.