(Phys.org) —From fish and chips to pork pies, some of London's tastiest foods create unappetizing and costly fat and oil buildups in drains. These fatbergs, as they are dubbed, end up in the city sewers system. A fatberg is a hefty clump of congealed fat and cooking oil, but also intertwined with other materials passing through the sewers. Leaders at two companies have a plan that, while not making lemonade out of lemons, will do even better, making energy out of leftover fat. Fat and oil from restaurants and build-ups in drains will find re-use as a result of an ambitious plan, it was announced on Sunday. The grease will be fed into what is claimed to be the world's largest fat-fueled power station, at Beckton in east London, to be run by energy company, 2OC.
Wastewater and water services provider, Thames Water, has signed a 20 year agreement with 2OC. That plant is set to produce 130 Gigawatt hours (GWh) a year of renewable electricity, enough to run 39,000 average-sized homes. (130 GWh is equivalent to the amount of electricity used by 39,394 households in a year based on an average household consumption. Thames Water will buy 75 GWh of this output to run its sewage works and a desalination plant. Remaining power will be available for the national energy supply grid. Other fuel sources include oil wastes from food manufacturers, processors and tallow.
Andrew Mercer, chief executive of 2OC, said that when Thames does not need the output, it will be made available to the grid. The power, he said, "will be sourced, generated and used in London by Londoners." Mercer told the BBC that there would be no smoke and no smell. The plant should be up and running by 2015.
Thames water each year removes 80,000 blockages in 109,000km of sewers. Clearing these blockages costs £1 million a month.
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