New York City to Use Food Waste to Heat Homes
New York City will reduce the amount of food waste sent to landfills by converting it into energy. Last week, Deputy Mayor Cas Calloway announced that the city will partner with Waste Management to deliver pre-processed organic waste food to Newtown Creek Wastewater Treatment Plant where it will be added to wastewater sludge to increase biogas production. The biogas by-product will be converted into renewable natural gas for both residential and commercial use through a partnership with National Grid, an international electricity and energy company.
Through this project, enough energy could be produced to heat almost 5,200 New York city homes and reduce annual greenhouse gas (GHG) emissions by over 90,000 metric tons, equivalent to removing almost 19,000 cars from the road. In addition, the project will help the city reach its PlaNYC goal of reducing municipal GHG emissions by 30 percent by 2017, a goal it is more than halfway to achieving.
Published date, Dec 27, 2013
What is biogas?
Biogas typically refers to a gas produced by the breakdown of organic matter in the absence of oxygen. It is a renewable energy source, like solar and wind energy. Furthermore, biogas can be produced from regionally available raw materials such as recycled waste and is environmentally friendly.
Biogas is produced by anaerobic digestion with anaerobic bacteria or fermentation of biodegradable materials such as manure, sewage, municipal waste, green waste, plant material, and crops. It is primarily methane (CH
4) and carbon dioxide (CO2) and may have small amounts of hydrogen sulphide (H
2S), moisture and siloxanes.
The gases methane, hydrogen, and carbon monoxide (CO) can be combusted or oxidized with oxygen. This energy release allows biogas to be used as a fuel; it can be used for any heating purpose, such as cooking. It can also be used in a gas engine to convert the energy in the gas into electricity and heat.
Biogas can be compressed, the same way natural gas is compressed to CNG, and used to power motor vehicles. In the UK, for example, biogas is estimated to have the potential to replace around 17% of vehicle fuel. It qualifies for renewable energy subsidies in some parts of the world. Biogas can be cleaned and upgraded to natural gas standards when it becomes bio methane.