The Norwater factory where Hoyer motors are being used in reverse osmosis systems.
The Norwater factory where Hoyer motors are being used in reverse osmosis systems.

Motors supplied by a Danish supplier, Hoyer Motors, are being used in reverse osmosis systems in Norway.

Norwegian company Norwater produces freshwater systems to vessels and rigs in the marine, fish farming and offshore industries.  It provides fresh water for the salmon farming industry and for chemical carrier ships.  Since 2005, more than 400 RO systems have been assembled at Norwater’s production facility on the west coast of Norway and shipped all over the world. Recently, the salmon farming industry has generated additional demand for freshwater production.

Hoyer electric motors are used on the high-pressure pumps which pressurise seawater at between 65-75 bar in the RO systems. The fresh water is used by the crews of ships and offshore rigs for drinking, cooking and washing. On chemical carrier ships, a two-stage RO system can be used to provide extra clean freshwater for cleaning the chemical tanks in between cargos. 

On ships, the alternative source of freshwater is evaporators, which use excess heat from the main engine, but this is expensive when fuel costs are high.