The works could see Thames Water become the UK’s largest on-site solar power producer and industrial user and help it achieve its target of reducing its greenhouse emissions by 20% on its 1990 levels by 2015.

Under the deal, Ennoviga Solar will initially install photovoltaic systems at three key sites in London, which will help Thames Water generate green energy from sunlight using solar panels.

According to the water company, the scheme will save around £100,000 a year off its electricity bill, providing 0.5% of its 1,180GW hours, £80 million annual energy requirement for processing and pumping 2.6 billion litres of water a day and 2.8 billion litres of sewage a day.

This is in addition to the 16% Thames Water already generates from anaerobic digestion of sewage.

Thames Water commercial director, Dr Piers Clark, said: “With the price of energy forecast to increase above inflation, the way we’ve structured this agreement will give us cheaper, renewable source of power from a secure source over the long term,

“We think this is the right thing to for our 14 million customers and to help move Britain that little bit closer to becoming a low-carbon economy.”

The installations are part of a wider programme which will see Thames Water fit photovoltaic systems at up to 100 of its smaller locations, helping to deliver a further 0.5% if the firm’s annual energy requirement.

Thames Water energy and carbon manager, John Gilbert said that Thames Water is trying to develop a portfolio of renewable energy projects to help reduce costs for its customers by using initiatives such as feed-in tariffs.

However, he added that the government has to play a part. “We are waiting to see the outcome of the government review into feed-in tariffs. Our view is that it makes financial sense for us and our customers and we believe we are showing leadership by starting this initiative.”

Gilbert also said that the cost savings for customers are likely to exceed the savings of £100,000 a year as energy prices rise.

As a result of the London-based installations, which will be large enough to cover 15 football pitches, an annual output of more than 4,500 megawatt hours of electricity will be created.

Stefano Gambro, director at Ennoviga, said that while the UK is behind schedule to replace its power stations that the feed-in tariff scheme, which launched in April last year, is encouraging companies such as Thames Water to exploit “otherwise unusable space to generate clean electricity.

“When energy prices rise and carbon charging starts, the impact on Thames Water customers’ bills will now be that little bit less.”

Carys Matthews

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