The Hawaiian Electric Company is the electric utility serving the City of Honolulu and together with its two subsidiaries, the Hawaii Electric Light Company, and the Maui Electric Company, it serves a total of 376,500 utility customers on the islands of Oahu. Hawaii. Maui, Molokai and Lanai. Approximately 76 percent of the electric energy in Hawaii comes from oil burning power plants, about 13 percent from coal, 4 percent from bagasse, 3 percent from municipal waste, 2 percent from geothermal steam and 1.5 percent from hydroelectric sources. All utility gas in Hawaii comes from oil. The Hawaiian Electric Company is the national leader in the application and general commercial acceptance of heat pump water heating. Since 1980, over 600 commercial-size heat pump water heaters have been installed in Hawaii. Over 300 apartment buildings with over 35,000 living units, some 30 hotels, 8 hospitals and numerous restaurants and lauderettes have replaced their central gas water heating systems with commercial-size heat pump water heaters. This exceptionally efficient electrotechnology permits hotels and apartments to extract significant amounts of solar energy from our warm sub-tropical atmosphere or to recycle waste heat from the building's air conditioning system for water heating. Heat pump water heaters discharge thermal energy from their condensers that is 2.5 to 6.5 times greater than the electric energy that they consume. Existing gas and oil-fired water heater efficiencies will vary from 0.50 to 0.75 depending on their age, their duty cycle, their adjustment and the cleanliness of their heat exchange surfaces. As a result, these conventional fuel fired water heaters consume 3 to 12 times more energy than the heat pumps that replace them (see Table 2 and Table 3).
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