Seawater Air Conditioning – What is it?

Ever heard of seawater air-conditioning? The seventies brought an energy crisis that drove scientists, engineers, and other concerned individuals to focus their minds on a much-cheaper energy source alternative.

Thus, they considered developing an air-conditioning system using seawater.

Initial studies, however, encountered a lot of problems. First of all, the cost for SWACS (seawater air-conditioning system) was not yet properly determined because the appropriate pipelines needed were not yet built.

To make matters worse, there were still a lot of unknowns with regard to the heat exchangers. Through continuous studies, OTEC (Ocean Thermal Energy Conversion) was able to develop more useful and reliable types of pipelines and heat exchangers.

Fundamentals of SWACS

Cold seawater can be taken from the bottom of the ocean or from the lakes. Other specific places like Hawaii and Fort Lauderdale and Miami in Florida are also favorable spots.

SWACS makes use of the following main components: a heat exchanger, freshwater distribution system, and seawater supply system. For maximum efficiency, you can adjust these three factors to suit the climate, location, and type of facility this system is installed.

Cold water is pumped deep either from the ocean or from the lake. It then passes through a heat exchanger, which is usually contained in a cooling station.

It is now the heat exchanger’s job to transfer heat from the freshwater distribution loop to produce cold water, which will be later distributed all throughout the building for air-conditioning.

Sometimes it is economical and practical to use auxiliary chillers. To supply deep cold seawater to maintain minimum temperature is, more often than not, impossible or remote.

First, seawater cools the chilled freshwater using a heat exchanger; then an auxiliary chiller is used to secondarily cool it.

As long as the coolness of the condenser is maintained, it can work efficiently.

Benefits of Seawater Air-conditioning

SWACS functions similarly to a conventional air-conditioning system. However, if it comes to economic savings and environmental friendliness, SWACS is a better choice.

SWACS can help you save approximately 90 percent of energy used. In most companies, air-conditioning cost is quite huge, approximately two-thirds of which is for chillers’ and cooling towers’ operations. SWACS’s chillers last longer than that of a conventional air-conditioning system. Moreover, it hardly depends on any future price changes of energy. But it should be noted that though this system has low operating cost, it has a high capital cost.

The use of SWACS also minimizes pollution and greenhouse effect.  This system doesn’t depend on fossil fuels, reducing air pollution and acid rain. It also prevents greenhouse effect since it uses a simple heat exchanger instead of a CFC-producing chiller machinery. CFCs (chlorofluorocarbons) cause the continuous depletion of our ozone layer.

Viability of SWACS

Site location is one of the major factors that determine the overall viability of SWACS. Others are the following:
·    Air-conditioning load size
·    Utilization of the air-conditioning system
·    Electrical costs
·    Onshore distribution system
·    Distance offshore to cold water

SWACS is one of the most vital energy source alternatives because of its economic and environmental benefits.

Though the system is not altogether perfect, it has potential in helping us curb the continuing rise of energy prices. What’s more, we can keep our own planet Earth clean, free, and safe for all of us to live in.