Chennai Metrowater, India in an interesting project, implemented in 2005, is generating electricity through bio gas from sewage sludge The electricity is being used to operate its sewage treatment plants in the city.The savings are reported to be about US$ 1million per annum. The project is expected to get carbon credits allotted as it is using alternate source of energy.The initiative should inspire other cities also.Source: hindu.com.The news is here. h*tp://www.hindu.com/2007/06/03/stories/2007060307500100.htm