Answer
Sea water desalination is already a widely used process responding to the constant and urgent water need of some countries. The use of nuclear power plants for the necessary electricity production has been implemented and the economy shows it is viable and economical.
Background
Sea water desalination has turned to be an extremely important need for potable water. The 21st century has to deal with fresh water supply crisis due to the population growth and to increasing needs for industrialization and urbanization. Sea water desalination is becoming a key to survival in some areas and a condition to help prevent many diseases.
It already exists in a few countries. The main techniques today are evaporation for high purity or reverse osmosis. This last process can use heat or electricity produced by nuclear power plants. Examples of sea water desalination can be found in Kazakhstan Aktau NPP (now under decommissioned) together with district heating, in Japan in Ohi, Takahama, Genkaï and Ikata nuclear power plants and in many other countries. New countries are now extremely interested and planning to implement together with electricity production for the country. The desalination process through heat of nuclear power plants is economically viable as demonstrated in existing facilities.
The operating experience as shown on the diagram here under demonstrates the maturity of the process and its viability.
