New York City's sewage treatment plants will now be in the
business of harvesting and selling renewable energy. Heating
fuel will be extracted from sludge, butanol (a gasoline
alternative) extracted from the algae that grows in wastewater
and, of course, methane gas will be captured from sewage plants'
digesters. The city's residents create 1.3 billion gallons of
wastewater daily, which results in a daily yield of 1,200 tons
of sludge being sent to landfills. The city is looking for
vendors to turn that sludge into renewable energy, fertilizer,
and paving and building materials. City officials plan to have
contracts by 2013. The city sewage plants already use half of
the methane produced by the digesters to provide about 20
percent of the electricity used by the plants, but now they'll
be putting the rest on the market. The Newtown Creek Wastewater
Plant in Brooklyn already has a contract in the works with
National Grid that will provide enough methane gas to heat 2,500
homes. The city is also looking to buil