Hawaii’s geographical isolation has made it that much more critical that the state develop renewable energy technologies and wean itself off expensive fossil fuels for transportation and electricity. The Hawaii Clean Energy Initiative, a partnership between the U.S. Department of Energy and the State of Hawaii formed in 2008, “aims to transform Hawaii into a world model for energy independence and sustainability.” The goal is to improve energy efficiency and produce 40 percent of the needed energy from renewable sources by 2030.
In the first 10 months of 2010, more than 300 homeowners and developers were granted variances to the state’s solar mandate. The law requires that all new single-family homes use solar water heaters, but exemptions are available for those who would prefer to use certain efficient gas-powered heating systems. The state’s Energy Office said it was unaware that the Hawaii Legislature had expressed the desire that the gas exemption only be available for those who would be living in the homes and paying the energy bills.
Boston-based energy company First Wind officially broke ground on a 30-megawatt project in Kahuku on Oahu‘s North Shore in mid-July and expects to be generating electricity in a matter of months. It is projected to produce enough electricity to power 7,700 homes and reduce the state’s consumption of oil by 150,000 barrels annually.
Marine Corps Base Hawaii commander Col. Robert Rice says sending soldiers overseas to secure a flow of oil from unstable nations is not a sustainable strategy. Out of concern for national security, he hopes to make Marine Corps Base Hawaii self-sufficient with renewable energy within five years.
Hawaii imports petroleum for about 90 percent of its energy needs, making it the most oil-dependent state in the country. Residents here pay more for their electricity and fuel than almost all other Americans. Of all the energy consumed in the state, about one third is used for ground and sea transportation and one third is used for air transportation. The residue of the refining process — after higher value gasoline, diesel and jet fuel are extracted — is used to create electricity. This medium- and low-sulfur fuel oil, generally called residual oil because it is the residue of the refining process, is thick and gooey and generally must be heated to even move through a pipe. It has few other uses.
Renewable energy initiatives have swept across the country and the world, and Hawaii is no exception. The Hawaii Clean Energy Initiative has shined light on new technologies that could become more prominent soon. They include biofuels, biomass, geothermal, hydropower, ocean wave and ocean thermal, solar, waste-to-energy and wind. By focusing on the “low-hanging fruit” of efficiency and conservation, state officials hope to reduce Hawaii’s overall energy demands.
It is important to note that some renewable technologies, particularly solar and wind, provide intermittent power so their true output is considerably less than their full capacity. The ratio of actual output to capacity is known as capacity factor.
Biofuels, Biomass and Waste-to-Energy
Biofuels are solids, liquids and gases made from living or recently living organisms that are burned for energy. This includes trees, grasses, algae, ocean plants, agricultural and food processing wastes, manure and garbage, according to the Hawaii Department of Business, Economic Development and Tourism‘s Energy Division.
Biomass for energy has a long history in Hawaii. Sugar plantations that once dotted the islands burned bagasse — the bulk of the cane plant left after the valuable juice had been squeezed out – to provide steam that turned turbines to create electricity. The plantation used what it needed and the rest of the electric power was sent to the island grids. At one time some Hawaiian islands got up to half their electricity from these renewable resources. Hawaiian Commercial & Sugar on Maui, the last remaining plantation in Hawaii, still sells up to 16 MW of power to Maui Electric Company. On Oahu, Hawaiian Electric’s new 110-MW Campbell Industrial Park Generating Station is fueled entirely on biodiesel and the Hawaiian Electric companies have received ten responses to a call for proposals to create biofuels from crops of all kinds grown in Hawaii.
The natural heat of the earth, found near areas of volcanic activity, can also be harnessed for electricity.
Puna Geothermal Venture has had its fair share of controversy stemming from complaints from the Native Hawaiian community, but delivers up to 30 megawatts of electricity to the grid, supplying some 20 percent of the Big Island’s power. Some in the Native Hawaiian community object to any use of geothermal energy, saying it conflicts with their religious beliefs.
At present, geothermal energy is only produced on Hawaii Island at the 30-MW Puna Geothermal Venture plant. That company, a subsidiary of the Israeli owned Ormat company – has proposed expanding its plant by 8 MW in the immediate future. The company is also exploring other geothermal resources in Puna, on the slopes of Hualalai in West Hawaii and on Maui on the slopes of Haleakala. In the 1980s, a 500-megawatt submarine cable was under discussion, but the project did not prove to be economical so was not pursued further.
Water flowing from the mountains to the sea can be used to produce electricity. As Hawaii has no fast running rivers and even its shallow and slow moving streams are often dry, there are limited possibilities for hydropower in Hawaii. Because damming rivers to create the massive lakes that are often used for hydro-power on the mainland and elsewhere can do a great deal of environmental damage, hydropower is no longer considered an attractive renewable energy in many cases. As Hawaii can not produce hydropower, it is often removed from mainland totals when comparing Hawaii to other states.
Electricity can be generated from ocean waves, tides and currents.
The difference in temperature between the warm ocean surface and the cold depths below powers a heat engine.
Energy from the sun can be used to heat water in a system called solar thermal, to produce electricity via photovoltaic panels or for concentrating solar power, a system in which the sun’s heat is reflected to heat a “working fluid” that becomes steam and turns a turbine to produce electricity.
Some 80,000 buildings in Hawaii use solar water heaters, and state income tax credits as well as federal tax credits are available for those who decide to install them. The Hawaii Energy Efficiency Program promotes incentives for solar water heaters.
In 2008, the Hawaii Legislature passed a solar “mandate” that requires all new single-family dwellings seeking permits beginning Jan. 1, 2010 to use solar water heaters. Homeowners can seek exemptions to the law if their home does not get enough sunlight; if they already use photovoltaic, wind or another renewable technology to heat their water; or if they install efficient, tankless, instantaneous gas-powered heaters.
A bill that failed in the 2010 legislative session proposed a Property Assessed Clean Energy program that would have used a state bond to loan home- and business-owners money to cover upfront costs of installing clean energy options like solar photovoltaic panels on their roofs. The loans would have been paid back through county-managed property taxes.
Most of the photovoltaic electricity production in Hawaii is distributed generation on private homes and government, institutional and commercial buildings. As of December 31, 2009, PV was providing at least 13 MW of electricity across the Hawaiian Electric service territories, including Oahu with at least 5.2 MW, Maui County with at least 4 MW, and Hawaii Island with at least 3.4 MW. Hawaiian Electric companies operate a net energy metering system by which PV owners can export excess electric power to the grid and receive full retail credit for that energy, up to the extent of the power they take from the grid.
The largest utility-scale PV facility in the state is Castle & Cooke’s La Ola 1.2 MW system on Lanai. Other utility scale projects are planned in Kapolei and Mililani. Sopogy presently operates the only concentrating solar power system, a .5 MW pilot system at NELHA near Kailua-Kona on Hawaii Island, and has plans for a much larger system in West Oahu.
Wind is created when pockets of air heated at different rates by the sun move in relation to one another. The use of wind energy is not entirely a new idea. Native Hawaiians named the different winds and then harnessed them, particularly tradewinds from the northeast, to propel their sailing canoes.
Today, both large-scale and small-scale wind turbines are capturing the wind’s energy and converting it to electricity. In Hawaii, the effort started in earnest in the 1980s with the first commercial wind farms at Kahuku on Oahu’s North Shore. Based in part on maps showing where the wind blows strongest, other projects have been created in recent years.
In 2006, wind farms opened near Hawi on the Big Island (10 megawatts) and Kaheawa on Maui (30 megawatts). A year later, a 20.5-megawatt wind farm began operating at South Point on the Big Island. The Kaheawa project expanded its capacity by more than 60 percent. Maui generates 51 megawatts from 35 wind generators on the ridgeline at Maalaia and near Ulupalakua., and Boston-based First Wind also broke ground in July 2010 on a 30-megawatt wind farm at Kahuku. A 2012 report done for the state predicted that wind, solar and geo-thermal sources of energy offered the best prospect for ending Hawaii’s dependence on oil generated power.
- Hawaii Department of Business, Economic Development and Tourism
- Senate Energy and Environment Committee Chair Mike Gabbard
- House Energy and Environmental Protection Committee Chair Hermina Morita
- Hawaii Public Utilities Commission
- Hawaiian Electric Company
- Maui Electric Company
- Hawaii Electric Light
- Kauai Island Utility Cooperative
- First Wind
- Xtreme Power
- Clipper Windpower
- Castle and Cooke
- Honolulu Project of Waste Energy Recovery
- Hawaiian Commercial and Sugar
- Puna Geothermal Venture