NYC’s wastewater to become new source of energy
The New York Times outlines ways that the New York City Department of Environmental Protection hopes to generate energy from the 1.3 billion gallons of wastewater that enters the city’s sewage treatment plants daily.
Heating fuel can be extracted from sludge and butanol, an alternative fuel to gasoline, from the algae generated by wastewater. Sewage treatment plants could sell methane gas to provide power to homes. Such projects represent a more sustainable long-term approach to managing a wastewater treatment process that costs the city about $400 million annually, not including capital investments.
Other byproducts from the sludge could take on more traditional uses as fertilizer or as paving and building materials. The most profitable energy source in wastewater treatment, though, is methane captured in sewage plants’ digesters. The City already uses about half the methane collected in its 14 plants’ digesters to meet a fraction of the energy demands of those facilities, but the remaining half could be pumped back into the grid.