Deep water source cooling (DWCS) or deep water air cooling is a form of air cooling for process and comfort space cooling which uses a renewable, large body of naturally cold water as a heat sink

Heat sink

A heat sink is a term for a component or assembly that transfers heat generated within a solid material to a fluid medium, such as air or a liquid. Examples of heat sinks are the heat exchangers used in refrigeration and air conditioning systems and the radiator in a car...

. It uses water at a constant 277 to 283 kelvin

Kelvin

The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...

s (4 to 10 degrees Celsius) or less which it withdraws from deep areas within lakes, oceans, aquifers and rivers and is pumped through the primary side of a heat exchanger. On the secondary side of the heat exchanger, cooled water is produced.

Advantages

Deep water source cooling has several advantages:

• It is very energy efficient, requiring only 1/10 of the average energy required by conventional cooler systems.
• It does not use any ozone depleting refrigerant. This is still an important feature, despite the fact that smaller/less expensive ecologic cooling devices also exist.

Disadvantages

Several disadvantages are also present:

• It requires the presence of a (fairly) large and deep water quantity in the surroundings. To obtain water in the 3 to 6 °C (37 to 43 °F) range, a depth of 66 metres (216.5 ft) is required.

• The set-up of a system is expensive and labor-intensive. The system also requires a great amount of source material for its construction and placement. For example, the pipes alone can range several hundreds of meters or feet when placed end to end.

External links

• Makai Ocean Engineering
• Honolulu Seawater Air Conditioning