Leftover grease and oil from restaurants will power a new combined heat and power (CHP) station at Beckton in East London.
The plant, developed and run by 2OC and financed by a consortium led by iCON Infrastructure, is set to produce 130 Gigawatt hours (GWh) a year of renewable electricity. Thames Water has agreed to buy 75 GWh of this output to run Beckton sewage works, which serves 3.5 million people, and the nearby desalination plant, which is operated in times of drought or other emergencies. The remaining power will be sold to the national energy grid.
The water firm has also committed to provide at least half of the fuel the generator requires to run – in the form of 30 tons a day of fat, oil and grease – enough to fill a six-meter-long shipping container – that would otherwise clog up London’s sewers. Leftover, low-grade cooking oil and food fat will be collected from food outlets and manufacturers. Solidified grease, such as from lamb and chicken, will be harvested from ‘fat traps’ in restaurant kitchens and from pinch-points around the capital’s sewer network. Thames Water already must spend $1.5 million a month clearing blockages in London’s sewers caused by solidified grease and oil. Now, that grease can help generate electricity. The rest of the power plant’s fuel will come from waste vegetable oils and animal fat.
It is Thames Water’s sustainable fuel commitments, worth more than $300 million over the long term, that have enabled the $107 million construction project to go ahead.
London-based J Murphy and Sons will build the plant, which is due to be operational in the first quarter of 2015. The power the water company has committed to buy accounts for 6 percent of the 1.2 Terrawatt hours (TWh) of power a year it requires to run its water and wastewater networks serving 14 million people across London and the Thames Valley.
Fourteen percent of Thames Water’s total power requirement is currently self-generated from renewable sources, including solar (pictured). The Beckton CHP plant will increase this to more than 20 percent.
2OC’s CHP plant has an overall efficiency in the high 90s percent, and electrical efficiency of more than 55 percent. Renewable waste heat from the engine will be used in the adjacent gas pressure reduction station owned by National Grid, enabling it to turn off existing gas heaters. Additional renewable heat from the power station is due to be put to beneficial use at the sewage works and also made available to local housing projects.