Many of the world's climate scientists believe that the build-up of heat-trapping CO2 in the atmosphere will lead to global warming unless we burn less fossil fuels. At the same time, energy must be supplied in increasing amounts for the developing world to continue its growth. This work discusses the feasibility of increasingly efficient energy use and the potential for supplying energy from sources that do not introduce CO2. The book analyzes the prospects for Earth-based renewables: solar, wind, biomass, hydroelectricity, geothermal and ocean energy. It then discusses nuclear fission and fusion, and the relatively new idea of harvesting solar energy on satellites or lunar bases. It will be essential reading for all those interested in energy issues.