There are about 440 commercial nuclear power reactors operable in 31 countries, with over 380,000 MWe of total capacity. About 65 more reactors are under construction. Some 56 countries operate a total of about 240 research reactors and a further 180 nuclear reactors power around 150 ships and submarines.
The science of atomic radiation, atomic change and nuclear fission was developed from 1895 to 1945. From 1945 attention was given to harnessing this energy in a controlled fashion for naval propulsion and for making electricity.
The world will need greatly increased energy supply in the next 20 years, especially cleanly-generated electricity. Electricity demand is increasing much more rapidly than overall energy use and is likely to almost double from 2004 to 2030.
Powerful accelerators may be linked to conventional nuclear reactor technology in an accelerator-driven system (ADS) to transmute long-lived radioisotopes in used nuclear fuel into shorter-lived fission products.
Like coal and gas-fired plants, nuclear power plants use cooling to condense the steam used to drive the turbines that generate the electricity. Once-through, recirculating or dry cooling may be used. Most nuclear plants also use water to transfer heat from the reactor core.
The nuclear power industry has various arrangements for cooperation among utilities, and internationally, among government and United Nations nuclear agencies. The World Association of Nuclear Operators is a valuable means of international assistance.
Energy storage on a large scale has become a major focus of attention and research as intermittent renewable energy has become more prevalent.
National and regional grid systems connecting generators with wholesale customers are just as important as electrical power generation. Investment in these is often on a similar scale to generation capacity.
Fast neutron reactors offer the prospect of vastly more efficient use of uranium resources and the ability to burn actinides which are otherwise the long-lived component of high-level nuclear wastes. Some 400 reactor-years' experience has been gained in operating them.
The International Framework for Nuclear Energy Cooperation (IFNEC), developed from the former Global Nuclear Energy Partnership (GNEP), is a partnership of countries aiming to ensure that new nuclear in initiatives meet the highest standards of safety, security and non‐proliferation.
Lithium-7 has two important uses in nuclear power due to its relative transparency to neutrons. As hydroxide it is necessary in small quantities for safe operation in PWR cooling systems as a pH stabilizer, and as a fluoride it is also expected to come into much greater demand for molten salt reactors.
Molten Salt Reactor use molten fluoride salts as primary coolant, at low pressure. Much of the interest today in reviving the MSR concept relates to using thorium (to breed fissile uranium-233).
Fusion power offers the prospect of an almost inexhaustible source of energy for future generations, but it also presents so far insurmountable scientific and engineering challenges.
Nuclear power capacity worldwide is increasing steadily, with over 60 reactors under construction in 13 countries. Most reactors on order or planned are in the Asian region. Significant further capacity is being created by plant upgrading.
As concern about anthropogenic climate change has grown, a number of high-profile environmentalists have decided that this is a more serious problem than their previous concerns with nuclear power.
Increasing energy demand, plus concerns over climate change and dependence on overseas supplies of fossil fuels are coinciding to make the case for increasing use of nuclear power.
Thorium is more abundant in nature than uranium. It is fertile rather than fissile, and can be used in conjunction with fissile material as nuclear fuel. The use of thorium as a new primary energy source has been a tantalizing prospect for many years.