The Honolulu Seawater Air Conditioning (HSWAC) Project involves installing a 63-inch high-density polyethylene pipe offshore Honolulu to a depth of 1,700 feet for a distance of approximately 5 miles. Cold seawater (~45°F), at the rate of 44,000 gallons per minute, will be pumped through a heat exchanger and returned to the ocean through a second pipe. The cold seawater will receive the heat from a freshwater distribution network beneath the streets of downtown Honolulu, which will be used to cool approximately 65 buildings.

TEC’s support of HSWAC includes preparation of State of Hawaii and National Environmental Policy Act Environmental Impact Statements and applications for all of the discretionary environmental and land use permits that will be required prior to project implementation by federal, state, and county agencies. The project has required investigations of offshore bathymetry, coral reefs and water quality, as well as historic properties and archaeological resources along the distribution route and preparation of a cultural impact assessment.