The displacement of non-renewable fossil fuels by renewable energy resources has occurred at a low rate in the USA. But a large number of drivers is expected to cause significant expansion of the US renewable energy industry in the near future. Included among the extrinsic drivers, or those that are not directly related to renewable energy resources, are reductions in natural gas and crude oil supplies and the OPEC Effect. An assessment of petroleum crude oil and natural gas consumption and reserves supports the position that supply problems and significant cost increases will start to occur in the first and second quarters of this century. Among the intrinsic drivers, or those that are directly related to renewable energy resources, are global warming and specific government incentives and mandates such as Renewable Portfolio and Fuel Standards that require the commercial use of renewable energy resources. The increasing US dependence on imported crude oil and environmental and political issues will drive the growth of the renewable energy industry and result in the gradual phase-out of what can be called the Fossil Fuel Era. By the end of this century, the dominant commercial energy mix in the USA is projected to include major contributions by renewable energy resources to help satisfy energy and fuel demands. Practical solutions to the problems of disposing of spent nuclear fuels and the development of clean coal applications will enable these energy resources to afford major contributions also. (C) 2002 Elsevier Science Ltd. All rights reserved.
