It is among the largest wastewater treatment plants in the world - Brooklyn, NY (called Newtown Creek).

Besides treating sewage, it has another common bond: it is ready to position National Grid as an industry leader in delivering renewable gas to its customers.

The gas is produced in anaerobic digesters – large air-tight tanks where microbes break down the sewage, producing a gas and a liquid digestate that can be used as fertiliser. The resulting gas is 60% methane and 40% carbon dioxide. New equipment owned by National Grid will then remove the carbon dioxide and other unwanted ingredients from the gas, making sure it is the right quality for injection into National Grid’s gas distribution systems. Newtown Creek will heat around 2,500 homes and reduce 14,500 tonnes of CO2 emissions annually.

“Another great benefit of this gas is that it can be used to deliver green heat in existing gas appliances,” says Donald Chahbazpour, Director, Sustainable Gas Group in the US. “And the best part of Newtown Creek is that National Grid has the opportunity to deliver a renewable source of energy that is cost competitive with traditional supply sources.”

In addition to sewage, biodegradable sources such as household waste and farming residues can be used to produce renewable gas. A company study in 2009 showed renewable gas has the potential to supply up to half of the UK’s residential gas demand and make a significant contribution towards the UK’s renewable energy targets. And, as the UK’s natural gas supply declines, this will also strengthen the nation’s diversity and security of supply.