Fossil fuel reserves and potential resources are under constant evaluation. New deposits are found by exploration and by applying new extraction technologies, but the consumption rates of such fuels are increasing, mainly in developing countries. Because such resources are finite, they cannot be sustainable for a long time. Coal deposits are more abundant that oil and gas, but they too will come to an end. To avoid geopolitical tensions, it is necessary to use new sources of electricity production; it was this need that was at the root of the development of nuclear power for electricity production. The world growth of electricity production and the depletion of fossil fuels are the reasons why international institutions (NEA, 2008) are encouraging the construction of new nuclear power plants, and why individual countries, even countries with large reserves of gas and oil (such as the United Arab Emirates), have already embarked on the construction of nuclear power plants.

The steady substitution of oil and gas by nuclear power stations will moderate the effects of the increasing unavailability and potentially increas­ing prices of oil and gas as reserves diminish. Although uranium and thorium resources are large, they are also finite and will only be made sustainable for many centuries with the introduction of fuel reprocessing and breeder reactors. Such technology is already available. Fuel reprocessing is com­mercially conducted in France, the UK and other countries; fast breeder reactors, up to a technological and even commercial demonstration level, have been operated for years in France, the UK, Russia and Japan. New developments are now being considered and there are no intrinsic problems that could prevent the full commercial deployment of such technologies. Although these considerations are difficult to evaluate in numerical terms, they are clearly on the benefits side.