Using sea water (we certainly have lots of it) to cool downtown buildings is an innovative idea and apparently more eco-friendly. Honolulu would join such places as Cornell University in Ithaca, New York; Stockholm, Sweden; and Bora Bora, French Polynesia in using seawater air conditioning in place of perhaps more costly methods.
How exactly does the system work? From the Advertiser:
The proposed system would draw seawater from a 63-inch-diameter pipe tunneled under the reef off the Kaka'ako peninsula, then along the ocean floor to a point about 2,200 feet offshore. At that point, water 1,600 feet deep is about 45 degrees Fahrenheit.
The cold seawater would then be run through a heat-exchanger to chill fresh water that would be piped into individual building air-conditioning systems. Warmed seawater resulting from the process would be pumped back into the ocean.
Honolulu Seawater estimates that the system can shave at least 14 percent from a typical office building electricity bill based on oil prices of $70 a barrel. Oil prices this year have ranged roughly from $50 to $80 per barrel, with an average of almost $70.
The company also said using the reusable resource from the ocean would eliminate the need for 174,000 barrels of fuel oil necessary to make electricity for air-conditioning.
Photo courtesy of the Advertiser.