U.S. Geothermal Provides Raft River Update

BOISE, IDAHO, Jun 19 (MARKET WIRE) --
U.S. Geothermal Inc. ("U.S. Geothermal") (TSX: GTH)(AMEX: HTM), a
renewable energy company focused on the production of electricity from
geothermal energy, announced a project update on the Raft River Unit I
geothermal power plant in Idaho. The net electrical power output of the
plant is currently between 10.5 and 11.5 megawatts. With four production
and four injection wells in operation, the maximum net electrical output
achieved by the plant during March, April and May were 11.2, 12.0, and
11.7 megawatts respectively. The power plant operated at 99% availability
during the same period, including scheduled maintenance.

A computer model of the reservoir volume, pressure and temperature has
been completed by an independent expert and is now being used to
investigate possible production and injection well strategies to increase
power production and to evaluate alternative well locations and
capacities. As part of the program to test the reservoir, geothermal
fluid from the power plant is being injected into production well No. 5,
which has resulted in increased pressure stability within other nearby
production wells and improved plant performance. This injection test is
ongoing.

Final "punch list" construction activities are still being completed by
Ormat Nevada. Project operating costs have been higher than budgeted due
primarily to winter startup issues, chemical treatment of cooling water,
and environmental monitoring and compliance activities. While the
production well issues are being addressed, the project is purchasing
power for the production pumps from a third party.

The electrical power from Raft River Unit I is being sold under a
full-output contract to Idaho Power Company. Under the terms of the
contract, power prices vary by season, with lower prices paid during the
spring months of March through May at 73.5% of the contract price, and
are paid at 120% of the contract price during the summer and winter peak
months of July-August and November-January. The remaining months are paid
at the 100% price level. The renewable energy credits contracted to Holy
Cross Energy of Colorado have been registered with Western Renewable
Energy Generation Information System so they meet the Colorado Renewable
Portfolio Standard requirements. It is anticipated that the first
payments due that have been accrued will be received during the current
quarter and then payments are expected on a monthly basis thereafter.

About U.S. Geothermal:

U.S. Geothermal is a renewable energy development company that is
operating geothermal power projects at Raft River, Idaho and San Emidio,
Nevada and testing a new well at Neal Hot Springs in eastern Oregon.

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

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, including statements
regarding potential energy resources and projects, development
possibilities for Raft River, San Emidio and Neal Hot Springs. 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. 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.

The TSX and American Stock Exchanges do not accept responsibility for the
adequacy of this release.

Contacts:
U.S. Geothermal Inc.
Saf Dhillon
Investor Relations
1-866-687-7059
(604) 688-9895 (FAX)
Email: saf@usgeothermal.com
Website: www.usgeothermal.com

Scott Peyron & Associates, Inc.
Melinda Keckler
(208) 388-3800
(208) 388-8898 (FAX)
Email: mkeckler@peyron.com

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