Practical and Economical

Nearly all tropical island nations have a relatively uniform need for air conditioning. Traditional electrical air conditioning systems (HVAC systems) are energy intensive and represent 35% to 45% of energy use in typical office buildings and hotels in tropical island communities.

     As a general rule of thumb, the amount of cold seawater required to generate one megawatt (1 MW) of electrical energy from and OTEC plant will provide the equivalent of 10 MW of air conditioning or process cooling. This implies that in certain instances where the air conditioning load density is concentrated in shoreline areas in close proximity to an OTEC facility, the plant will not only provide base load power to the local community, but also reduce load requirements by nearly 40% by supplying cold water air conditioning! Likewise, in areas too developed which restricts the construction of an OTEC plant directly adjacent to a load center with reasonable access to deep cold water, SeaWater Air Conditioning (SWAC) can provide a cost effective, environmentally attractive energy technology on its own.

Additional Benefits 

     The effluents from an integrated OTEC system or SWAC facility can be further utilized in appropriate locations to improve water quality in local harbors or marinas by providing necessary flow rates to "flush" the harbor or similar relatively stagnant water resource. This could significantly improve water quality in the harbor or marina over current practice. Also, since the effluent streams still possess significant "cold" or heat absorption capabilities, utilization as process cooling in conjunction with conventional power plants or industrial facilities is also an option. Providing cooling waters at significantly reduced temperatures from ambient sources currently employed would significantly improve plant efficiencies above current practices.

     Air conditioning and cooling with deep, cold seawater for some coastal communities situated in the tropical island regions of the world is economically and technically viable today. SWAC in conjunction with an integrated OTEC system, or stand alone, is most attractive to communities with three or more of the following features (1) the community is sufficiently close to a source of cold seawater, (2) the overall air conditioning demand is large — more than 1000 tons, (3) the local cost of energy is high, (4) the air conditioning utilization is high (air conditioning required year-round, as is inherent in tropical ocean communities), (5) the onshore distribution is not extensive (easy access to the air conditioning load centers). Under these circumstances, energy savings can be greater than 80% and air conditioning costs significantly reduced.