Replacing carbon fuels with renewable energy sources is clearly a necessary goal for a sustainable future. A recently released report by the Intergovernmental Panel on Climate Change has examined the prospects of attaining this goal by 2050. Scientists analysed over 160 scenarios to calculate the potential of renewable energy to meet the world's energy needs in 2050. The most optimistic scenario predicts that renewables will constitute 80% of our energy matrix given that certain conditions are met. Renewable energies considered are bioenergy, solar energy, geothermal energy, hydropower energy, ocean energy and wind energy.