Thames Water sewerman Danny Brackley digging out 'fatberg' blockages, a mixture of food fat and wet wipes, under Leicester Square in central London.

Water and wastewater services company Thames Water has signed a £200 million, 20-year deal with green utility company 2OC, to provide ‘at least half of the fuel’ needed to power ‘the world’s largest fat-fuelled power station’ in Beckton, East London.

The combined heat and power plant (CHP), developed by Blue NG (a joint venture between the National Grid and 2OC) and financed by a consortium led by iCON Infrastructure (and comprising EEA Holdings Ltd and Deutsche Bank), is set to produce 130 Gigawatt hours (GWh) a year of renewable electricity - enough to power 39,000 homes.

Thames Water has now announced that from 2015, it will be collecting ‘solidified grease’ (such as that from lamb and chicken), from ‘pinch-points’ around London’s sewer network and from ‘fat traps’ in restaurant kitchens.

On top of this, Thames Water will also collect ‘leftover, low-grade cooking oil and food fat’ from food outlets and manufacturers to form half of the CHP plant’s required daily fuel allowance - around 30 tonnes of fat, oil and grease per day. However, this amount is expected to increase over time.

The rest of the power plant’s fuel will come from waste vegetable oils and tallow (animal fat).

The fats will then be burned to create about 130 gigawatts (GWh) of power each year, enough to run 39,000 average-sized homes.

Thames Water has said it will buy back 75 GWh of electricity to power Beckton sewage works – which serves 3.5 million people – and the nearby desalination plant. This will reportedly boost the amount of renewable energy the company uses from 14 per cent to 20 per cent.

The remaining power from 2OC’s plant will be sold on to the National Grid.

“Sourced, generated and used in London by Londoners”

Commenting on the deal, Andrew Mercer, Chief Executive of 2OC, said: “This is good for us, the environment, Thames Water and its customers. Our renewable power and heat from waste oils and fats is fully sustainable. When Thames doesn’t need our output, it will be made available to the grid meaning that power will be sourced, generated and used in London by Londoners.”

Piers Clark, Commercial Director for Thames Water, added: “This project is a win-win: renewable power, hedged from the price fluctuations of the non-renewable mainstream power markets, and helping tackle the ongoing operational problem of ‘fatbergs’ in sewers."

According to Thames Water, it costs one million pounds a month to remove 80,000 fat blockages from 109,000 kilometres of sewers per year.

Paul Malan, Senior Partner of iCON Infrastructure, said: “We are delighted to have become the lead investor in the Beckton project. It is at the heart of the capital’s infrastructure and has the long-term support of customers of the highest calibre.”

Power station background

Beckton won unanimous approval from Newham Borough Council and then the London Thames Gateway Development Commission in 2009.

However, the project attracted criticism from some environmental organisations, including Biofuels Watch, who voiced concern over the health and environmental impacts of burning biofuels.

London-based construction company J Murphy and Sons will build the plant as part of a £70 million construction deal. It is expected the plant will be operational ’in the first quarter of 2015’.

According to 2OC, the £70 million plant will have an overall efficiency ‘in the high 90s per cent’ and ‘world beating’ electrical efficiency in excess of 65 per cent.

The company has said that ‘waste heat from the two-stroke engine will be used in the adjacent gas pressure reduction station allowing existing gas fired boilers to be turned off’ while additional renewable heat will be made available ‘for any housing schemes nearby’.

However, successfully filtering heat from CHP plants in the UK has in the past proved notoriously difficult due to the cost and nuisance of implementing the required infrastructure.

Speaking in Resource 53, AEA’s Practice Lead on Waste Management and Resource Efficiency Dr Adam Read said: “CHP can be really difficult to integrate with existing local energy systems. You can find yourselves having to dig up pavements left, right and centre. So, it’s quite disruptive, it’s quite costly, and given the UK situation, which has always been about cheap landfill, it doesn’t tend to be very good value for money.”

Read more about the Beckton Combined Heat and intelligent Power plant.