Haven Power, the specialist supplier of electricity to UK businesses, has signed a deal with Thames Water worth more than £500million over the next five years.

Haven, which is based on Ransomes Europark in Ipswich, and is part of Drax Group, will supply Thames Water with 100% renewable electricity, with the deal including an option for two further five-year renewals which could increase the overall value of the contract to more than £1.5billionn over 15 years.

Haven sources its power from the Drax power plant in Yorkshire, which, following conversion to biomass, is now the UK’s single largest supplier of renewable energy.

The deal will enable Thames Water, which already sources about 20% of its electricity through self-generated renewables such as solar, wind, hydro and biogas, to meet all of its electricity needs from renewables.

Peter Bennell, chief executive of Haven Power, said: “Customers in all walks of life are increasingly demanding a sustainable approach and Thames Water’s use of renewable power is a fantastic example for other businesses to follow.

“From SMEs right up to large commercial and industrial business, our Renewable Power option is an excellent way for companies to improve their sustainability credentials – and it doesn’t cost the earth.”

Thames Water energy manager Angus Berry added: “Our energy and carbon strategy centres around reducing costs for customers and minimising our impact on the environment. This deal with Haven puts downward pressure on bills and means we will now be using 100% renewable electricity.

“We look forward to growing our relationship with Haven to exploit further opportunities to minimise energy costs and emissions, as well as continuing to work towards our ambitious target of self-generating 30 percent of our own electricity by 2020.”