The Alaska SeaLife Center is visited by approximately 160,000 people annually and spends a lot of electricity and money in keeping the center warm for the visitors. The center sources most of the electricity from utility companies producing power using conventional means and hence emitting a lot of carbon dioxide into the delicate environment. To reduce energy bills and also emissions, the center has turned off all boilers that burn expensive fuel and has swapped that will north seawater heat pump system that taps a summer’s worth of solar energy stored in the Resurrection Bay.
The system sucks in warm seawater, extracts heat from it and then returns it back to the ocean. Costing about $830,000, the system is expected to pay for itself in less than nine years, thereby saving at least $15,000 while also offsetting 1.3 million pounds of carbon emissions each year. The water in the bay is coldest, 37 degrees, in April, while in October the sun raises that temperature to 52 degrees, giving it the potential to heat facilities.
The heated water from the bay is piped to a titanium heat exchanger to heat up a mix of glycol and water before cold water is returned to the ocean. The glycol mixture moves by pipe to a heat pump where it comes into contact with refrigerant causing the liquid refrigerant to boil, turning it into gas. The gas is then run into an electric compressor that compresses the gas and hence increases its temperature. The compressed gas again raises the temperature of another loop of water, which is then pumped throughout the building to warm ventilation air. The efficient system produces three uunits of heat for every unit of electricity.