The U.S. Bureau of Land Management office in Utah is moving along on approval for a new, 20-MW geothermal power plant proposed by ENEL Cove Fort LLC.
The agency in August put out for comment a draft environmental assessment on the project, got no comment on it and on Oct. 19 a decision record was signed by the agency.
In April 2010, ENEL Cove Fort submitted to the agency a Plan of Utilization for Geothermal Development on Federal Leases UTU-29557, 85605 and 81048 (Geothermal Utilization Plan). This is a 20 MW (net) Organic Rankine binary cycle power plant, with production and injection pipelines, and a substation and electrical transmission line, said the draft EA. Drilling of additional production and injection wells would be necessary.
“The power plant would be constructed on private land owned and/or leased by ENEL,” the draft EA said. “Construction of the proposed facility is scheduled to begin in 2012 and be completed by December 2013 with commercial operation by March of 2014. The proposed power plant would be an air cooled facility thus the 20 MW output is a yearly average output. The proposed action involves use of six existing geothermal water production wells and three existing injection wells. Five of the production wells are located on federal land (USFS), one on private land. Two of the injection wells are also located on federal land (BLM), one on private land. Twelve additional wells are analyzed as contingency locations and could be drilled over the 20-plus year life of the project. Five existing steam wells would be plugged and reclaimed; one existing steam well would be used as a monitoring well. About 6.6 miles of 8 to 36-inch pipeline would be installed to carry water from the production wells to the power plant and from the power plant to the injection wells. Installation of a new four-acre electrical substation and about 1,600 feet of 138-kV power line is also proposed.”
The proposed project is located about 3 miles south of Cove Fort, Utah, approximately 2.7 miles south of Interstate 70 and two miles east of Interstate 15 in Beaver and Millard counties, Utah.
An Organic Rankine, binary cycle geothermal plant consists of two, independent, closed systems used to operate the plant: a geothermal brine loop system (first system), and a turbine driving process loop system (second system), BLM noted. A Rankine cycle is a cycle that converts heat into work. The Organic Rankine cycle is named for its use of an organic high molecular mass fluid, in this case isobutane, with a lower boiling point than the geothermal water. The isobutane will allow the Rankine cycle to convert low-temperature heat in water to drive a turbine and create electricity.
The power that would be delivered from the facility, built on the site of a prior geothermal project, would be transmitted to customer service centers through an existing 138-kV transmission line operated by PacifiCorp.
Said the website of Enel Green Power: “In March 2007, Enel Green Power North America (EGP-NA) acquired a non-generating geothermal plant located in Cove Fort, Utah. The project site lies about 175 miles south of Salt Lake City, overlapping Beaver and Millard Counties. EGP-NA is planning to construct a new geothermal power plant with an installed capacity of up to 65 MW, to be completed in various phases. The first phase of the project is expected to be commercially operating by the end of 2013. The Cove Fort plant will use an air-cooled binary system, also known as a closed-loop system, to generate electrical power.”