Deep Sea Water Air Conditioning
Seawater air conditioning (SWAC) is an alternate energy system that uses the cold water from the deep ocean (and in some casesadeep lake) to cool buildings. In some areas it is possible to reduce dramatically the power cohsumed by air conditioning systems; SWAC can be cost effective and attractive investment. it is an alternate energy for air conditioning.
Benefits of SWAC system:
The seawater air condition systems taps intoasignificant and highly valuable natural energy resource that is available at some coastal locations. The benefits ofaseawater air conditioning system include:
Large energy saving approaching 90%.
Short economic payback period.
Costs are nearly independent of future energy prices increases.
No evaporation water consumption.
Cold seawater availability for secondary applications.
Main Components and Basic Process
There exist three main components of deep water cooling.These basic components can be optimized for each specific location,climate and building.
1) A sea/lake water open loop supply system which pumps deep cold water throughaheat exchanger and returns the warm water throughashallow outfall
2)Fresh water closed loop system pumps warm water through the cooling station heat exchanger and distributes the cooled water among commercial,residential and institutions for air conditioning.
3)Heat exchanger(cooling station)transfers heat from the fresh water distribution loop resulting in cold water for air conditioning purposes.
Sea water air conditioning has many environmental advantages over that of conventionala/csystems:
1)90%reduction in energy consumption
2)Decreased reliance on fossil fuels
a)reduced air pollution
b)reduced acid rain
c)reduced impact on global warming
d)reduced ecological&political impacts of resource extraction
e)no use of ozone-depleting chlorofluorocarbons(CFCs)
The economic viability ofaSWAC system is site specific.Each location has unique opportunities as well as problems.The main factors influencing the economic viability ofa specific location include:
The distance offshore to cold water:shorter pipelines are more economical than long pipelines.
•The size of the air conditioning load:there is an economy of scale associated with SWAC- systems less than 1000 tons are more difficult to justify economically.
•The percent utilization of the air conditioning system:The higher the utilization throughout the year,the higher the direct benefits.
•The local cost of electricity:Ahigh cost of electricity makes conventional AC more costly and SWAC,in comparison,more attractive.Any cost analysis should include current and future costs of electricity.
•The complexity of the distribution system on shore:SWAC works best withadistrict cooling arrangement,where many buildings are cooled taking advantage of the economy of scale. SWAC is even more economical if this distribution system is compact.