Doosan Enpure has signed the deal with Severn Trent Water, a British water supplier, Doosan Heavy said.
The plant is capable of producing some 1 megawatt worth electricity and heat, according to Doosan Heavy.
In June, the Doosan Heavy unit also won a 87.5 billion-won deal to build a water purification facility.
In 2012, Doosan Heavy acquired Enpure in a bid to strengthen its desalination business. (Yonhap)