These investments would begin to pay off in about 2040, when the savings would start to outweigh the costs.

“If oil prices rise faster than predicted, and if we factor in the costs of climate change and the impact of fossil fuels on public health, the pay off occurs much earlier,” added the report.

It stated that by 2050, power, transport, industrial and domestic energy needs could be met with only isolated residual uses of fossil and nuclear fuels. Energy efficiency in buildings, vehicles and industry would be a key ingredient, as would increasing energy needs met through electric power which would be renewably generated and supplied through smart grids.

WWF director and ex-Nedbank CEO Tom Boardman said that the report had a big vision and made bold plans, but that it was enormously powerful to know that an alternative energy future was possible.

Various energy scenarios have been developed by different organisations, which take into account different factors and use different models, aiming to predict what we kind of an energy mix the world could expect going forward.

WWF South Africa climate change programme manager Richard Worthington explained that the report aimed at establishing that fossil fuel reliant energy scenarios, such as those put forward by the International Energy Agency and Shell, were not the only realistic ones.

Boardman noted that the report would likely not sit well with vested interests, and emphasised that it was not without its challenges, but that he hoped it gathered momentum.

The weighty report was commissioned by WWF with analysis from consultancy Ecofys, and took two years to compile.

In a nutshell, the scenario assumed that in 2050, energy demand was 15% lower than in 2005, because although population, industrial output, passenger travel and freight transport continued to rise as forecast, energy efficiency enable more to be done with less.

Industry would use more recycled and energy efficient materials, buildings would be constructed or upgraded to need minimal energy for heating and cooling, and there would be a shift to more efficient transport.

As far as possible, electrical energy would be used instead of solid and liquid fuels. Wind, solar, biomass and hydropower were the main sources of electricity, and solar, geothermal and heat pumps would provide most of the heat for buildings and industry.

“Because supplies of wind and solar power vary, smart electricity grids would have to be developed to store and deliver energy more efficiently,” the report said.

Bioenergy, namely liquid biofuels and solid biomass, would be used as a last resort where other renewable energy sources were not viable, particularly in providing fuel for aeroplanes trucks and ships, and industrial processes that required very high temperatures.

“We need a concerted approach to low-carbon reindustrialisation to achieve the growth rates required in renewable energy technology industries. This means moving away from the baseload fallacy that renewables are insufficient to support industrialised society,” emphasised Worthington.

“The report is more than a scenario – it is a call for action. We can achieve a cleaner renewable future, but we must start now,” said WWF DG Jim Leape.