Commercial energy is required for development, but its production and use can also cause serious environmental impact in the form of acid drainage, methane emissions and mining wastes; oil spills from on-shore and off-shore installations and from ships; air pollution by sulphur dioxide (SO2), NOx and carbon dioxide (CO2) when coal, oil or gas are burned; and radioactive containment, leakage and storage problems by nuclear power generation. Existing pollution preventing technologies have been available but may not be implemented because of financial costs and lack of political will. This is despite evidence to suggest that technological application to reduce pollution can reduce long-term operational costs by increasing energy efficiency. Reducing pollution from commercial energy generation may, therefore, protect the environment and increase energy efficiency, and both are considered essential in order to achieve sustainability.In all regions, future levels of atmospheric pollution will be governed largely by the use of energy from fossil fuels. The Intergovernmental Panel on Climate Change has predicted that global economic output may double between now and 2050, with energy demand reaching nearly three times that in 1990 (IPCC 1995). If the developing countries follow the conventional development path, there would be a massive increase in the emission of atmospheric pollutants. However, this need not be the case - as has been proved by some developed countries. For example, in Europe, sulphur emissions peaked in the 1970s and subsequently declined steadily, despite increasing energy consumption. Similarly, the mechanisms developed for the [Kyoto Protocol] could help developing countries restrict their emissions of greenhouse gases.