Despite making deals related to renewable energy Shell remains major player in oil and gas. : Shell said Wednesday it had signed a deal to purchase power from a development dubbed "the world's largest offshore wind farm." The 15-year power purchase agreement relates to 240 megawatts from Dogger Bank C, the third and final phase of the 3.6 gigawatt Dogger Bank Wind Farm, which will be located in waters off the coast of northeast England.