Future energy needs will require a multi-stranded approach, combining renewable energies for example, solar, wind, hydro technologies and bio fuels. If you think about these energy sources they are all derived directly from the sun. Plants use photosynthesis to produce chemical energy from the sun, hydro technologies, excluding wave, are produced by solar evaporation causing rainfall and wind is produced by uneven heating of the earth’s surface by the sun causing air to move from higher to lower pressure regions. Renewable energies are relatively non polluting, sustainable and efficient. They reduce global CO2 emissions’ and the emission of greenhouse gases.