A case study was carried out for the production of 150 m3/hr boiler feed water from sea water at a coastal thermal power station in southeastern India. Three alternatives, viz. multistage-flash (MSF), thermocompression (TC), and reverse osmosis (RO) were considered. The first two are thermal desalination processes and the last one is an ambient temperature membrane process. In the case of the thermal desalination processes, extraction steam at appropriate temperature and pressure drawn from the power plant was considered. Since the water from thermal desalination plants will be very pure, only mixed bed downstream polishing units will be required to reach boiler feed water quality, but for the RO process, a full fledged demineraliser (DM) plant will be necessary. It was found that a system with a locally manufactured MSF unit will be the most economical for the purpose. Emphasis is placed on local capability to manufacture and install desalination plants. © 1990.