On May 21, 2012, U.S. Geothermal Inc. (the "Company") entered into a purchase agreement (the "Purchase Agreement") with Lincoln Park Capital Fund, LLC ("LPC"), pursuant to which the Company has the right to sell to LPC up to $10,750,000 in shares of the Company's common stock, par value $0.001 per share ("Common Stock"), subject to certain limitations and conditions set forth in the Purchase Agreement and imposed by the Company's board of directors and pricing committee thereof.

Pursuant to the Purchase Agreement, LPC initially purchased $750,000 in shares of Common Stock at $0.38 per share. Thereafter, the Purchase Agreement provided that on any business day and as often as every other business day over the 36-month term of the Purchase Agreement, and up to an aggregate amount of an additional $10,000,000 (subject to certain limitations) in shares of Common Stock, the Company has the right, from time to time, at its sole discretion and subject to certain conditions to direct LPC to purchase up to 250,000 shares of Common Stock, which amount may be increased in accordance with the Purchase Agreement if the closing sale price of Common Stock on the NYSE MKT LLC exceeds certain specified levels. The purchase price of shares of Common Stock pursuant to the Purchase Agreement will be based on prevailing market prices of Common Stock at the time of sales without any fixed discount, and the Company will control the timing and amount of any sales of Common Stock to LPC. No sales of Common Stock under the Purchase Agreement will be made through the Toronto Stock Exchange. As of December 21, 2012 an aggregate of $1,420,549.92 has been sold pursuant to the Purchase Agreement.

On December 21, 2012, the Company and LPC entered into an Amendment No. 1 to the Purchase Agreement (the "Amendment") to reduce the total amount that can be purchased under the Purchase Agreement, including amounts already purchased, from $10,750,000 to $6,500,000. All other provisions of the Purchase Agreement remain in full force and effect.

All shares of Common Stock to be issued and sold to LPC under the Purchase Agreement have been and will be issued pursuant to the Company's effective shelf registration statement on Form S-3 (Registration No. 333-170202), filed with the Securities and Exchange Commission in accordance with the provisions of the Securities Act of 1933, as amended, and declared effective on December 1, 2010, and the prospectus supplements thereto dated May 22, 2012 and December 21, 2012.

This current report on Form 8-K shall not constitute an offer to sell or a solicitation of an offer to buy any shares of Common Stock, nor shall there be any sale of shares of Common Stock in any state or jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or other jurisdiction.

A copy of the form of the Amendment is filed herewith as Exhibit 10.1 and is incorporated herein by reference. The foregoing description of the Amendment is qualified in its entirety by reference to such Exhibit. This Current Report on Form 8-K is being filed in part for the purposes of incorporating Exhibits 10.1 by reference into the Shelf Registration Statement.

(d) Exhibits

Exhibit  Description
Number
  10.1     Amendment No. 1 to the Purchase Agreement with Lincoln Park Capital
         Fund, LLC, dated December 21, 2012*

* Exhibits are hereby incorporated by reference as exhibits to the Shelf Registration Statement.