For rough and ready calculations on nuclear-powered seawater desalination plants, the specifications made use of in Table 2 are based on an article by Jürgen Kupitz, head of the Section on Nuclear Power Technology Development, of the International Atomic Energy Agency. The following excerpt is from Kupitz's article, "Nuclear Energy for Seawater Desalination: Updating the Record," which appeared in the IAEA Bulletin:

"A desalination plant with a capacity of 1 million cubic meters per day could supply an urban concentration of 3 to 4 million people with sufficient potable water for domestic use. Such a desalination plant, using the RO [reverse osmosis] process, would require a nuclear plant having an installed capacity of about 300 MW-electric (MWe). The same urban concentration of people also would require between 4,000 to 6,000 MWe of installed capacity to provide their corresponding electricity needs. Hence, nuclear power plants in the upper end of the small and medium-size power range, and certainly the large-size nuclear power plants, would only constitute suitable choices when they are intended to supply electricity to consumers in addition to energy for seawater desalination. Thus, there is no reason why nuclear reactors could not supply both requirements simultaneously, and take advantage of the economic benefits accruing to large-size nuclear plants."

As Kupitz notes, "practically any type of nuclear reactor could provide the energy needed for desalination." The IAEA conducted a series of feasibility studies, including one in response to a request for assistance submitted by five North African states--Algeria, Egypt, Libya, Morocco, and Tunisia. This 1996 study identified a series of locations that required seawater desalination in the range of 20,000 to 720,000 cubic meters per day, by the year 2005. At present, there is a regional capacity of 1 million cubic meters per day, and in Saudi Arabia, the currently installed capacity for seawater desalination is about 4 million cubic meters per day.

The IAEA estimates that it would take $200-300 million for a multi-effect distillation system to be built, including the cost of the reactor.

The only industrial-scale nuclear reactor that supplies electricity as well as heat for desalination was built by the former Soviet Union, a BN-350 liquid-metal-cooled fast reactor, which went into operation in 1973. It is located in Aktau, Kazakstan (formerly Shevchanko, U.S.S.R.). Aktau has been operated since 1989 at a reduced thermal power level of 520 MW(th) with a maximum electric power production capability of 80 MWe, plus heat for the production of about 80,000 cubic meters per day of potable water.

There are several small nuclear-powered desalting plants that serve the in-plant needs of nuclear power stations in Japan, and Russia has about 16 small plants installed on nuclear ice-breakers and other nuclear-powered ships.