Deep-Seawater Air Conditioning System to Cool Honolulu

by , 12/08/09

sustainable design, green design, Honolulu Seawater Air Conditioning, Honolulu, deep-sea system, air conditioning, green energy, Waikiki, underwater technology

Frigid seawater pumped in from the ocean’s depths will soon help cool more than half of the buildings in Honolulu’s downtown. Honolulu Seawater Air Conditioning LLC, which is undertaking the $240 million project, expects its technology to cut the Hawaiian city’s air conditioning electricity usage by up to 75 percent while slashing carbon emissions and the use of ozone-depleting refrigerants.

Honolulu seawater cooling plan

The project involves running a five-foot-wide pipeline hundreds of feet below the sea, which will then suck up thousands of gallons of frosty water and discharge it through air-conditioning units around the city, helping to cool off entire buildings. The warmed water is then dumped back into the ocean at a level and temperature that won’t harm nearby aquatic life.

The company plans to break ground next summer with the first 40 buildings coming online in 2012. Hawaii’s power grid is especially taxed during the day, so the seawater cooling system will help save premium power while relieving stress on the grid.

If all goes well, the technology could be extended to nearby tourism-heavy Waikiki, which uses a significant amount of air conditioning. The deep-sea system, which is already used in cities like Stockholm and Toronto, will hopefully inspire other tropical coastal areas around the world to harness the underwater technology.

+ Honolulu Seawater Air Conditioning, LLC

Via AP and Environmental Science and Technology

Lead photo by Cliff1066

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  1. "Smart" Metal to Make A... July 19, 2010 at 12:39 pm

    […] developed by researchers at the University of Maryland could change all that by increasing the efficiency and reducing the emissions of air-conditioning and refrigeration systems by up to […]

  2. lizthewiz March 29, 2010 at 1:36 pm

    I am doing a science fair project on posible unforseen negative effects of this…..
    any suggestions?

  3. nycaircondition January 27, 2010 at 1:59 am

    Air conditioning New York, NYC air conditioning specializes in HVAC installation, air conditioning repair services, heating and air conditioning for commercial and residential uses. NYCaircondition New York City air conditioning service providers.

  4. feline74 January 8, 2010 at 7:01 pm

    This is (pardon me . . .) cool. I wonder if they’ve considered combining this with an OTEC power system?

  5. anorthernhiker December 25, 2009 at 7:12 pm

    I visited Hawaii earlier this year and I was Astonished that there wasn’t more solar and wind power being generated. Recycling is not carried out very well and is in Pilot project status. In a place that could be on the leading edge of environmentalism it is in it early stages. Too bad but this project is good to see that there is a start. Cold water cooling on downtown offices has been going on in Toronto for quite some time. The water is treated so that after cooling it is fed into the local water system and used again for domestic drinking water. The heat that would be absorbed is dissipated through the normal channels so that the effect is not any greater that the impact that the day to day discharge would produce.

  6. RayLee December 10, 2009 at 10:58 pm

    and wouldnt that mess up ocean current routes, location of certain species, and change pressures? I think that would be the long run effect… hmmm although cost effective… there are going to be spillovers. (positive and negative)

  7. RayLee December 10, 2009 at 8:46 pm

    and wouldnt that mess up ocean current routes, location of certain species, and change pressures?

  8. RayLee December 10, 2009 at 8:44 pm

    And wouldnt that mess up current routes and pressures?

  9. mattress December 10, 2009 at 11:16 am

    Won’t this warm up the ocean?

  10. kristenhall23 December 9, 2009 at 11:03 pm

    They are already doing this around Dubai – this was the plan for all those islands and urban regeneration projects. Its much more cost effective and much lower energy usage, but only really works on this district scale.

  11. Kirsten Corsaro December 8, 2009 at 2:13 pm

    Interesting! I wonder if this will be used in other cities as well. It seems that many coastal cities (like those in California) have moderate climates that don’t normally need air conditioning. I’m surprised that Stockholm uses it, although maybe the temperature difference between the water and air could also be used to generate heat.

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