Southern Water captures bio-gas to power Cogenco CHPs

Southern Water is investing £2.5 million on installing CHP plants at the works to capture bio-gas created during the waste water and sewage treatment processes.

This bio-gas, which would otherwise have been burnt off in a flare, can then be used to produce renewable energy - providing power and heat to the works, with any surplus exported to the National Grid.

As well as generating electricity, the 772kWe CHP plants also recover heat from the engine and exhaust systems via water from heat exchangers. This water is then used to warm the treatment tanks, helping speed up the bacterial digestion of the waste.

Generating electricity in this way will enable Southern Water to reduce its carbon emissions from the site by approximately 7,500 tonnes a year.

The project is part of Southern Water's multi million pound investment in carbon mitigation and energy efficiency schemes between 2010 and 2015. These will help reduce its carbon emissions and contribute to it's target of generating 20 per cent of its energy usage from renewable sources by 2020.

Morné Cloete, Southern Water Project Manager, said: "Harnessing recoverable energy through the use of CHP plants is just one of the innovative ways Southern Water is helping reduce its impact on the environment by reducing our carbon footprint while also cutting our energy costs."