"The Energy Report shows that in four decades we can have a world of vibrant economies and societies powered entirely by clean, cheap and renewable energy and with a vastly improved quality of life. The report is more than a scenario - it's a call for action. We can achieve a cleaner, renewable future, but we must start now," said WWF Director General Jim Leape.

The Energy Report outlines how 95% of global energy could be produced using current technology through:

• A 15% reduction in global energy demand by 2050 despite economic activity tripling, world population exceeding 9 billion;
• Renewable energy like wind, solar, and geothermal power replacing fossil fuel based energy, with 'smart' grids enabling increasing renewable energy supplies;
• Urban transport will be moved from fuel to electricity, as will a lot of domestic heat demand;
• Bio-energy will use residues from forestry, agriculture, the food industry, household waste, with limited bio-fuels using strict sustainability criteria.

By 2050, the global system wil have with immensely lower operating cost than "business-as-usual" fossil-based energy and related greenhouse-gas emissions reduced 80 percent from 1990 levels with obvious advantages in avoided climate change damage and adaptation costs.