Large-scale green energy systems can affordably replace fossil fuel as the world's primary source of electricity within 20 years, new research from the United States weather office suggests.
Critics in the U.S., notably those with links to electricity producers who rely on coaland natural gas-fired generation, argue that the uneven production of power from wind turbines yields only nominal reductions in greenhouse gas emissions compared to fossil fuels.
The differences in emissions are too small to justify the higher costs associated with wind - and solar - production, the argument goes.
However, a director with the U.S. National Oceanic and Atmospheric Administration (NOAA) said Friday in Vancouver that wind and solar could supply 70 per cent of electricity demand in the lower 48 states, with fossil fuel and hydro/nuclear renewables each accounting for just 15 per cent by 2030.
