BOISE, IDAHO--(Marketwire - June 21, 2012) - U.S. Geothermal Inc. (TSX:GTH)(NYSE Amex:HTM)(NYSE MKT:HTM), a leading renewable energy company focused on the development, production and sale of electricity from geothermal energy, is pleased to announce that its wholly owned subsidiary, USG Nevada LLC, has notified its customer NV Energy that Commercial Operation was achieved by the new 11.75 gross (8.6 net) megawatt Unit I power plant. Electrical energy from the new power plant is now being sold for $89.75 per megawatt hour ("MWH"), subject to a 1% annual escalator, under the terms of a 25 year power purchase agreement. The new power plant is projected to generate an average of approximately 71,500 MWHs of electrical power each year. The new power plant replaces an existing facility that, prior to being removed from service, generated approximately 23,000 MWH annually using the same production and injection wells.

Mr. Daniel Kunz, Chief Executive Officer of U.S. Geothermal Inc., said, "This is a major milestone for our company, the San Emidio project and the geothermal industry. New and innovative power production technology is now deployed for large-scale and highly efficient generation of electricity. The San Emidio Unit I project was beset with delays that were necessary to ensure that our contractor delivered a fully functional power plant. This new plant is now operating and delivering power on a commercial basis. We truly appreciate the formidable efforts of our employees and contractors and the confidence and patience of our lenders, customer, and shareholders over the last several months."

USG Nevada LLC expects to immediately file for the Section 1603 ITC cash grant of approximately $11 million for the project. Proceeds from the ITC grant will be used to repay an existing $7.5 million bridge loan and the balance will be available for general corporate purposes. The arrangement of long term financing for the project can now move forward. The project engineering, procurement and construction contractor is working to complete a final list of items required to achieve contract completion under a fixed price contract that includes financial guarantees for the original completion date and power output of the plant.

Please visit our Website at: [ www.usgeothermal.com ]

About U.S. Geothermal Inc.:

U.S. Geothermal Inc. is a leading renewable energy development company that is operating geothermal power projects at Raft River, Idaho and San Emidio, Nevada. The Neal Hot Springs project, located in eastern Oregon, is currently under construction and will be the company's third operating power project. The company holds geothermal energy rights to 69,500 acres comprising six advanced stage geothermal development projects.

The information provided in this news release may contain forward-looking statements within the definition of the Safe Harbor provisions of the US Private Securities Litigation Reform Act of 1995. These statements are based on U.S. Geothermal Inc.'s current expectations and beliefs and are subject to a number of risks and uncertainties that can cause actual results to differ materially from those described, including but not limited to, the results from the exploration, production and injection well drilling at San Emidio. Readers are cautioned to review the risk factors identified by the company in its filings with Canadian and US securities agencies. Forward-looking statements are based on management's expectations, beliefs and opinions on the date the statements are made. U.S. Geothermal Inc. assumes no obligation to update forward-looking statements if management's expectations, beliefs, or opinions, or other factors, should change.

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