British Prime Minister Gordon Brown set out goals Thursday to increase renewable-energy use in Britain tenfold by 2020. Brown’s vision for a “green revolution” is heavily reliant on wind power, with plans for 7,000 new turbines — 4,000 onshore and 3,000 offshore. The North Sea could turn “into the equivalent for wind power of what the Gulf of Arabia is for the oil industry,” Brown said. Britain aims to reach an E.U.-mandated target of sourcing 15 percent of energy from renewables by 2020, which will require an investment of nearly $200 billion, said Brown. But he envisions the U.K. cutting greenhouse-gas emissions by nearly 20 percent and oil dependency by 7 percent, and creating some 260,000 green-collar jobs. Enviros and Conservative Party leaders were cautiously optimistic about Brown’s plan, applauding his words but stressing the need to put them into action.