Nevada-based Ormat Technologies Inc. is planning to develop a geothermal energy project on the southwest side of Haleakala in Maui, Hawaii. The company is hoping to begin drilling exploratory wells next year to determine if there are sufficient geothermal resources. Operating the state’s only geothermal plant, located in the Puna District on Hawaii Island, Ormat has provided an outline of the Maui project proposal in an environmental impact statement preparation notice that was filed earlier this year with the state.
Before the company decides whether or not to build a geothermal power plant on Maui, officials have said that many questions regarding the characteristics of the project will need to be addressed. In a 2005 report for the state Department of Business, Economic Development and Tourism, a consultant concluded that there is enough theoretical geothermal potential to support a 35-megawatt facility on the site, enough to power approximately 23,000 households.
In order to determine if a power plant will be possible in the area, Ormat officials have said that the company will have to drill at least three exploratory wells and that it will probably be 12 to 18 months before wells can be drilled, taking into consideration the time needed to obtain necessary state and county permits. The company will have to complete a full environmental impact statement addressing the risk of earthquakes, potential lava flows from Haleakala, the possibility of penetrating aquifers that can contaminate drinking water, well emissions and impact on plants and animals. Ormat will also need to secure geothermal mining leases from the state and an expansion on the existing state geothermal resource subzone.
Hawaii Energy Office Officials say that geothermal power is an important part of the state’s renewable energy portfolio, as the consultant’s report estimated that geothermal resources in the area could generate the equivalent to the peak electrical load of the entire state.
The advantages of geothermal energy are that the steam produces firm, reliable power similar to a traditional oil-fired plant and the significant cost-savings that would be attributed to using geothermal power per kilowatt versus other methods such as solar power development. The prospecting of the geothermal resources in the state can be costly, as projects typically require test wells be drilled through rock layers to depths of over 6,000 feet.
Ormat has said that the exploration phase of the project will cover 5,315acres ranging in elevation from 200ft to 5,400ft, though the site of the possible power station itself would only occupy about 5acres. Ormat’s 38mw Puna Geothermal Venture facility saves Hawaii Electric Light Co. over 144,000 barrels of oil per year by providing enough electricity for 25,000 residents.