SciDev.Net: Renewable energy could play a much larger role in supplying the world’s energy needs than previously estimated — but it won’t come cheap, according to a new study. The research, presented at the International Scientific Congress on Climate Change in Copenhagen, Denmark, this week (11 March) says that renewable energy could supply 40 per cent of the world’s energy needs by 2050. The new estimate is considerably higher than previous projections, which put renewables’ share at …