A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nuclear fission is passed to a working fluid, which in turn runs through steam turbines. These either drive a ship's propellers or turn electrical generators' shafts. Nuclear generated steam in principle can be used for industrial process heat or for district heating. Some reactors are used to produce isotopes for medical and industrial use, or for production of weapons-grade plutonium. As of 2022, the International Atomic Energy Agency reports there are 422 nuclear power reactors and 223 nuclear research reactors in operation around the world.
Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants. Nuclear decay processes are used in niche applications such as radioisotope thermoelectric generators in some space probes such as Voyager 2. Generating electricity from fusion power remains the focus of international research.
Mixed oxide fuel, commonly referred to as MOX fuel, is nuclear fuel that contains more than one oxide of fissile material, usually consisting of plutonium blended with natural uranium, reprocessed uranium, or depleted uranium. MOX fuel is an alternative to the low-enriched uranium (LEU) fuel used in the light-water reactors that predominate nuclear power generation.
A breeder reactor is a nuclear reactor that generates more fissile material than it consumes. Breeder reactors achieve this because their neutron economy is high enough to create more fissile fuel than they use, by irradiation of a fertile material, such as uranium-238 or thorium-232, that is loaded into the reactor along with fissile fuel. Breeders were at first found attractive because they made more complete use of uranium fuel than light-water reactors, but interest declined after the 1960s, as more uranium reserves were found, and new methods of uranium enrichment reduced fuel costs.
Monju (もんじゅ) was a Japanese sodium-cooled fast reactor, located near the Tsuruga Nuclear Power Plant, Fukui Prefecture. Its name is a reference to Manjusri. Construction started in 1986 and the reactor achieved criticality for the first time in April 1994. The reactor has been inoperative for most of the time since it was originally built. It was last operated in 2010 and is now closed.
The Savannah River Site (SRS) is a U.S. Department of Energy (DOE) reservation in the United States in the state of South Carolina, located on land in Aiken, Allendale, and Barnwell counties adjacent to the Savannah River, 25 miles (40 km) southeast of Augusta, Georgia. The site was built during the 1950s to refine nuclear materials for deployment in nuclear weapons. It covers 310 square miles (800 km2) and employs more than 10,000 people.
The integral fast reactor is a design for a nuclear reactor using fast neutrons and no neutron moderator. IFR would breed more fuel and is distinguished by a nuclear fuel cycle that uses reprocessing via electrorefining at the reactor site.
A molten salt reactor (MSR) is a class of nuclear fission reactor in which the primary nuclear reactor coolant and/or the fuel is a molten salt mixture. Only two MSRs have ever operated, both research reactors in the United States. The 1950's Aircraft Reactor Experiment was primarily motivated by the compact size that the technique offers, while the 1960's Molten-Salt Reactor Experiment aimed to prove the concept of a nuclear power plant which implements a thorium fuel cycle in a breeder reactor. Increased research into Generation IV reactor designs began to renew interest in the technology, with multiple nations having projects, and as of September 2021, China is on the verge of starting its TMSR-LF1 thorium MSR.
The Watts Bar Nuclear Plant is a Tennessee Valley Authority (TVA) nuclear reactor pair used for electric power generation. It is located on a 1,770-acre (7.2 km²) site in Rhea County, Tennessee, near Spring City, between the cities of Chattanooga and Knoxville. Watts Bar supplies enough electricity for about 1,200,000 households in the Tennessee Valley.
Marcoule Nuclear Site is a nuclear facility in the Chusclan and Codolet communes, near Bagnols-sur-Cèze in the Gard department of France, which is in the tourist, wine and agricultural Côtes-du-Rhône region. The plant is around 25 km north west of Avignon, on the banks of the Rhone.
The Zero Power Physics Reactor or ZPPR was a split-table-type critical facility located at the Idaho National Laboratory, Idaho, USA. It was designed for the study of the physics of power breeder systems and was capable of simulating fast reactor core compositions characteristic of 300-500 MWe demonstration plants and 1000 MWe commercial plants.
Reactor-grade plutonium (RGPu) is the isotopic grade of plutonium that is found in spent nuclear fuel after the uranium-235 primary fuel that a nuclear power reactor uses has burnt up. The uranium-238 from which most of the plutonium isotopes derive by neutron capture is found along with the U-235 in the low enriched uranium fuel of civilian reactors.
India's three-stage nuclear power programme was formulated by Homi Bhabha, the well-known physicist, in the 1950s to secure the country's long term energy independence, through the use of uranium and thorium reserves found in the monazite sands of coastal regions of South India. The ultimate focus of the programme is on enabling the thorium reserves of India to be utilised in meeting the country's energy requirements. Thorium is particularly attractive for India, as India has only around 1–2% of the global uranium reserves, but one of the largest shares of global thorium reserves at about 25% of the world's known thorium reserves. However, thorium is more difficult to use than uranium as a fuel because it requires breeding, and global uranium prices remain low enough that breeding is not cost effective.
PRISM is a nuclear power plant design by GE Hitachi Nuclear Energy (GEH).
Small modular reactors (SMRs) are a proposed class of nuclear fission reactors, smaller than conventional nuclear reactors, which can be built in one location, then shipped, commissioned, and operated at a separate site. The term SMR refers to the size, capacity and modular construction only, not to the reactor type and the nuclear process which is applied. Designs range from scaled down versions of existing designs to generation IV designs. Both thermal-neutron reactors and fast-neutron reactors have been proposed, along with molten salt and gas cooled reactor models.
The BN-800 reactor is a sodium-cooled fast breeder reactor, built at the Beloyarsk Nuclear Power Station, in Zarechny, Sverdlovsk Oblast, Russia. The reactor is designed to generate 880 MW of electrical power. The plant was considered part of the weapons-grade Plutonium Management and Disposition Agreement signed between the United States and Russia, with the reactor being part of the final step for a plutonium-burner core The plant reached its full power production in August 2016. According to Russian business journal Kommersant, the BN-800 project cost 140.6 billion rubles.
ASTRID was a proposal for a 600 MW sodium-cooled fast breeder reactor, proposed by the Commissariat à l'énergie atomique (CEA). It was to be built on the Marcoule Nuclear Site in France. It was the successor of the three French fast reactors Rapsodie, Phénix and Superphénix.
Phipps Bend Nuclear Plant was a planned nuclear power generation facility that was to be constructed and operated by the Tennessee Valley Authority (TVA) in unincorporated Hawkins County, Tennessee. Proposed to house two reactor units, the power plant was estimated to cost $1.6 billion when it was first planned in late 1977, provide a generating capacity of 2,600,000 kilowatts. Following negative public reactions towards nuclear energy following the Three Mile Island accident and a decreasing demand for power due to regional economic decline, the TVA's board of directors voted to defer further construction of the power plant. By 1981, the plant was 40% complete and an estimated $1.5 billion in planning, engineering, and construction costs had accumulated. Construction never resumed, and the project was canceled overall in 1982 due to lower load growth than forecast. By the project's cancellation, the TVA had amassed over $2.6 billion in spending for the incomplete nuclear facility. After being auctioned off by the TVA in 1987, the land acquired for the plant would be under the ownership of Hawkins County's industrial development board, who converted most of the site into an industrial park. A 1 MW solar farm was built at the site in 2017.
Robert Louis (Bob) Ferguson was a nuclear-trained physicist and a 60-year veteran in the field of nuclear energy. He was best known for being appointed the first Deputy Assistant Secretary for Nuclear Energy Programs for the U.S. Department of Energy (DOE) by the first Energy Secretary, James Schlesinger, serving from 1978 to 1980 during President Jimmy Carter's administration.
