U.S. Geothermal Inc. Updates El Ceibillo Project; Drilling Commences

BOISE, IDAHO--(Marketwired - April 30, 2013) - U.S. Geothermal Inc. (TSX:GTH)(NYSE MKT:HTM), a leading renewable energy company focused on the development, production, and sale of electricity from geothermal energy, announced today that its wholly owned subsidiary, U.S. Geothermal Guatemala, S.A., started drilling well EC-1 at the El Ceibillo Project on April 29. Well EC-1 is planned for a depth of up to 1,000 meters (3,280 feet).

Well EC-1 is located approximately 114 meters (374 feet) from well B-7, a well drilled in 1999 that had a bottom hole temperature of 202°C (396°F) at 200 meters (656 feet) deep. In advance of finalizing the location for well EC-1, two geophysical surveys were completed during January and February that provided more detailed targeting information. A 262 station gravity survey, covering 2.2 square kilometers (.85 square miles), was conducted by MWH Geophysics of Reno, Nevada and a 12 station VES (Vertical Electrical Survey) was conducted by Sinergia of Guatemala City, Guatemala. Site work started on the project in January, with construction of an on-site office, property fencing, drill pad and test ponds.

An environmental study report "Construction and Operation of the Geothermal Electric Plant, El Ceibillo" was submitted to Guatemala's Ministry of Environment and Natural Resources in late December 2012. This report was submitted in compliance with the concession contract for the geothermal rights granted by the Ministry of Energy and Mines in April 2010, and with the Electrical Law and Regulation of Guatemala. The report was prepared by Eco-Servicios Integrados of Guatemala City, Guatemala.

The report underwent a public comment period which ended on January 29, and is now under formal review by the Ministry Of Environment and Natural Resources. No comments were received during the public comment period. Upon approval, an Environmental License will be issued that will allow the project to proceed with power plant construction and operation.

"We are very excited to begin development drilling on the El Ceibillo project in Guatemala," said Dennis Gilles, CEO of U.S. Geothermal. "With three operating power plants in the United States now providing positive EBITDA, net income, and cash flow, we expect that the development of El Ceibillo will be a strong contributor to the next stage of growth for our company. The government of Guatemala strongly supports renewable energy, and we look forward to working with them to make the development of this first, 100% private geothermal concession a big success."

Please visit our Website at: http://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, San Emidio, Nevada, and Neal Hot Springs Oregon. El Ceibillo is an advanced stage, high temperature development project located in Guatemala. 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 El Ceibillo. 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.