Hawaii's energy consumption

Summary: The US state of Hawaii has a low per-capita energy consumption rate and an unusual Gas Cap Law that limits the price of gasoline.

The only American state made up entirely of islands, Hawaii is also the furthest from the rest of the states, occupying the northern group of islands in Polynesia in the Pacific Ocean, 2,000 miles from the American west coast. Though not very populous, due to its small area it is the 13th most densely populated state. The per capita income is close to the national average, but the cost of living is much higher, especially in Honolulu, due in part to the cost of bringing raw materials to the islands from the mainland. Similarly, home prices are roughly double the national median, and Honolulu is the most expensive American city in which to buy a house. That same cost prevents exports from playing a major role in Hawaii’s economy—though coffee, macadamias, pineapple, and other agricultural goods are exported, they do not account for a major sector of the economy. Tourism has driven the economy since statehood in 1959. Hawaii is one of the only states to enact a Gas Cap Law, which sets a legal limit on the wholesale price of gasoline. The cap is set weekly by the Hawaii Public Utilities Commission, and is derived on prices in New York Harbor, the Gulf Coast, and Los Angeles. The price varies slightly in eight different zones of Hawaii, based on the varying cost of delivery to different islands.

Per capita energy consumption is quite low in Hawaii; in 2022 Hawaii's per capita energy consumption was the lowest in the United States. Transportation consumes roughly the same amount of energy as the residential, commercial, and industrial sectors combined—residential consumption is especially low, most households never requiring energy for home heating. About 80 percent of Hawaii’s energy comes from petroleum. There are no major pipelines in Hawaii, and crude oil arrives via tanker at its ports. The state’s two refineries on the island of Oahu use crude oil shipped from Alaska, as well as foreign imports as Alaskan production declines. Hawaii imported the majority of the energy it consumed, resulting in the highest energy prices in the nation. However, in 2015, the state legislature passed a law that requires all of Hawaii’s energy to come from renewable sources by 2045. In 2023, about 31 percent of the state’s energy came from renewable sources.

No liquefied natural gas import facility has yet been established in Hawaii, though feasibility studies have been conducted for potential future projects. Hawaii’s use of natural gas is extremely low—the lowest in the country—and what natural gas it does consume is produced at the synthetic natural gas plant in Oahu, which converts by-products from the oil refineries into a natural gas substitute. Hawaii is one of only three states to produce synthetic natural gas. More than half of it is consumed by the commercial sector, especially hotels and restaurants, for cooking and water heating. Very few households use natural gas for home heating; what residential consumption there is (about 20 percent of an already small amount) is primarily in the form of a stove fuel, or powers water heaters.

Biomass is a growing source of energy in Hawaii, and in mid-2011 the Kalaeloa plant on Oahu began tests to see if burning eucalyptus—abundant in the islands—would serve as an effective biomass fuel. The sugar plantations in Hawaii have long earned supplemental revenues by selling waste to be used as biomass or burning it themselves and selling the electricity, though today the only remaining plantation is Maui’s Hawaiian Commercial & Sugar, which burns sugar waste to produce 12 megawatts for sale to the local Maui Electric Company.

In Oahu, the HPOWER Garbage-to-Energy Plant generated 46 megawatts by burning municipal solid waste that would otherwise go to landfills, thus doubling as a waste management solution for a state with severely limited landfill capacity. In the 2010s, Oahu’s Honua Power Company began converting an abandoned sugar mill into a biomass gasification plant that would use waste from construction and demolition sites, scrap rubber, and nonrecyclable paper and plastic. The plant

Landfill gas is another energy generation method in Hawaii. Compressed solid waste in landfills results in methane gas, which is trapped in pockets, piped out of the landfill, and burned to power a turbine. Long in use in Hawaii, developers have recently initiated numerous additional landfill gas projects for possible implementation.

Hawaii is one of eight states with a geothermal power plant, the Puna Geothermal Venture on the Big Island. Producing 30 megawatts, the plant is operated by Hawaii Electric Light Company.

Hawaii is one of the top ten solar-producing states, though like all states, its full solar potential has not been realized yet. Recent years have seen several new solar installations constructed, though, including an 80 kilowatt solar power generator in Kauai built by DuPont, a new rooftop solar power installation at the Kona Commons shopping mall, and a 1.2-megawatt solar farm on Lanai.

The state is a frequent site for proposed wave energy projects, because of the power and frequency of the waves in its coastal waters, though not until recently were any of them actually implemented commercially. As of the 2020s, the Office of Naval Research was in the midst of testing a buoy that generates 40 kilowatts simply from the bobbing motion of the sea, and plans offshore platforms that will provide 2.7 megawatts from the rise and fall of sea swells. The project was undertaken by Australia-based Oceanlinx, and operates by keeping the platforms stable, so that as the sea level beneath them rises, it pushes air upward through a turbine.

Honolulu Seawater Air Conditioning, a project by St. Paul, Minnesota–based Ever-Green Energy, has recently begun a deepwater air-conditioning project in Hawaii, using some of the same personnel as the largest seawater air conditioning project in Europe (in Stockholm). Once construction has been completed, underground pipes will transfer deep ocean water from four miles offshore to a cooling station in Kakaako, which then provides district cooling to customers’ buildings. In the cooling station, the ocean water passes through a heat exchanger, chilling the freshwater in a closed loop pipeline system that is used for district cooling; the seawater, which never mixes with the water used for air conditioning, is returned to the sea at a slightly warmer temperature.

Bibliography

"Hawaii." US Energy Information Administration, 30 July 2024, www.eia.gov/state/?sid=HI. Accessed 31 July 2024.

"Hawai'i's Energy Facts & Figures." Hawaii State Energy Office, 2020, energy.hawaii.gov/wp-content/uploads/2020/11/HSEO‗FactsAndFigures-2020.pdf. Accessed 31 July 2024.

Miike, Lawrence H. Water and the Law in Hawaii. Honolulu: University of Hawaii Press, 2004.

Whitton, Kevin. Green Hawaii. Honolulu: Mutual Publishing, 2008.