Seawater airconditioning: A highly reliable and cost effective cooling source!
 
 
 
 
 

Technology
SeaWater Air-conditioning (SWAC) is a system that uses the cold seawater (between 6 and 10 °C) from a depth of approximately 700 meters as a coolant for air-conditioning systems of buildings (or as a coolant or as raw material for industrial processes, aquaculture, agriculture etc.) situated in a close radius. The cold seawater runs from the Poles over the ocean floor to the tropics. This is why in principle everywhere where there is a steep slope from the shore in to the deep ocean this cold water will be available.

The main components of a basic seawater air-conditioning system are:

  • a seawater supply system consisting of a deep seawater intake pipeline and a
    shallower effluent pipe,
  • a cooling station with pumps, heat exchanger and cold water sump and
  • a fresh water distribution system for the distribution to the customers.

    A basic seawater air conditioning system is illustrated in the above figure. The buildings are cooled with conventional air-conditioning. the conventional chillers of the buildings are replaced by the SWAC connection units (for example heat exchangers). The cooling capacity needed is then provided by the chilled (fresh) water distribution system. This system passes fresh water through the heat exchanger situated in the cooling station where cold seawater passes its low temperature on to the fresh water. Once the seawater has passed through the heat exchanger, it is returned to the ocean through an effluent pipeline. For protection and for aesthetic reasons the deep water pipe and the effluent pipe are buried in the upper layer of the ocean floor, at the shoreline landing until the cooling station. Because all the major parts of the Seawater air-conditioning system are proven technology this system is highly reliable.

    The system can reduce the total electric energy consumption and related CO2 emissions for cooling up to 90%, thus reducing total energy cost considerably. When properly designed and constructed the seawater air-conditioning system has no negative impact on the environment. Furthermore, the use of freon is reduced with 100%. As such the system contributes to a sustainable environment in a cost-effective manner.