Clean Energy presents a broad survey of the energy problems facing society over the coming decades and the prospects for their solution. The book emphasizes the importance of developing a strategy for the world's future energy supply. The strategy must take into account: the finite supplies of natural gas and petroleum; the increased consumption of fuel by developing economies; the concern over greenhouse gas emissions; the pollution caused by burning coal (especially coal with a high sulphur content); the difficulties and costs of extracting unconventional fossil fuels; and the technical, sociological and cost barriers that restrict the use of renewable forms of energy.