This New York Times piece talks about the city’s wastewater utility as if it were just discovering that waste is a resource. But that’s not fair: halfway down, it admits that “about half of the methane produced by the city’s plants is already used to meet about 20 percent of the energy demands of the city’s 14 sewage plants, whose electric bills run to a total of about $50 million a year. Now the city wants to market the other half, which is burned off and wasted.” Brooklyn’s Newtown Creek Wastewater Plant, for example, could contribute enough gas to the national grid to heat 2,500 homes.
The thing is, none of this is new. From my book: ” The Babylonians are credited with noticing that gas coming from sewage could be useful, as are the Assyrians. Marco Polo reportedly saw covered tanks of sewage—simple anaerobic digesters—in China. And Count Alessandro Volta, as well as inventing 14 the electric battery and giving his name to voltage, concluded in 1776 that there was a correlation between decaying organic substances and the amount of gas they gave off.” There are still lamps in Sheffield run on sewer gas. I am often asked what will change the flaws of waterborne sewage treatment (it uses too much clean water and too much energy, and wastes a rich resource). It will be money and energy concerns. And New York City’s DEP seems to agree.
Image copyright Alan Cordwell