Oslo, Norway - A report from the European Renewable Energy Council (EREC) and Greenpeace says that renewable energy, including wind, hydro, solar, biomass, and ocean power, could supply half of the world’s energy needs by 2050. The report was commissioned from the Department of Systems Analysis and Technology Assessment (Institute of Technical Thermodynamics) at the German Aerospace Centre (DLR).

Currently, renewable sources provide around 13 percent of the world’s energy. According to the “Energy (R)evolution”, that could increase to 50 percent while cutting global greenhouse gas emissions in half by 2050. The report aims to provide a “practical blueprint for how to urgently meet CO2 reduction targets and secure affordable energy supply on the basis of steady worldwide economic development.”

All that is needed are the right government policy which encourage renewable energy sources over fossil fuels, says the report. A large scale switch to renewables, greater energy efficiency, and the use of decentralized energy systems will help to achieve a 35% proportion of renewables by 2030, it says.

Centralized energy systems using fossil fuels are wasteful, achieving only around 22% efficiency, says the report.

The report warns that the time window for making the shift is relatively small, as many existing power plants in the OECD will come to the end of their useful life within the next decade, and investment decisions will be made in the next few years.

Contrasting against the International Energy Agency forecast

The International Energy Agency (IEA), in its World Energy Outlook projection, provides a “business as usual” scenario that would see greenhouse gas emissions almost double by 2050. According to IEA Director Claude Mandil, our energy future is “dirty, insecure and expensive”, but “new government policies can create an alternative energy future which is clean, clever and competitive”.

The Greenpeace/EREC report builds on some projections of the IEA, but makes different assumptions on the price of oil and future carbon dioxide penalties. In predicting that fossil fuels will continue to supply the majority of the world’s energy in the coming decades, the IEA forecasts that oil prices will dip slightly and then rise back to $55 a barrel by 2030.

The Greenpeace/EREC study predicts that oil prices will reach $100 a barrel by 2050, prompting an increase in energy efficiency and renewable energy.

The Greenpeace/EREC study also assumes that a greenhouse gas emissions trading system will be established in all world regions in the long term, with a carbon price of $50 per tonne by 2050. Renewable energy on the other hand, will continue to fall in price as technology is improved and greater economies of scale are realized. Technologies such as wind, solar, hydro and biomass will converge with traditional energy prices and to become more economically and environmentally beneficial. Greenpeace and EREC both advocate huge increases in solar power, seeking to make the next few decades the ‘solar generation’.

The Energy (R)evolution report can be read here (PDF).