Inside a decade, the availability of our conventional fuels will be doubtful. It is already late, then, to consider what sources we should develop. The principal requirement in addition to sufficient availability, at an acceptable cost, is that use of New Energy no longer involving injection of pollutants, in particular CO2 into the atmosphere. CH4 is a seldom mentioned danger: it comes increasingly with the rising temperature. This book covers six sources of renewable energy, starting with the popular ones such as solar and wind, but going on to others, waves, tides, hot rock geothermal and hydro. The feasibility in each case is analysed, stressing how the inexhaustible energies are all cheap after the collecting machinery has been paid for. This book focuses on the development of such renewable energies as well as the cost of these various alternatives. The author, Professor John O'M Bockris is a world renowned researcher and the author of many essential texts.