Geothermal Energy Act - =Title I: Loan Guarantee Program= - Authorizes the guarantee of loans by financial institutions for commercial development of geothermal resources. Limits such loan guarantees to 75 percent of the project costs. Requires repayment of such loans in 30 years, and limits such loans for any project to $25,000,000.

Authorizes the payment of the interest on such loans by the Secretary of Interior if the borrower is unable to pay the interest and such payment is in the public interest.

Establishes the Geothermal Resources Development Fund in the Treasury to carry out the loan guarantee and interest payment provisions of this title.

Authorizes the appropriation of not in excess of $50,000,000 annually to carry out the loan guarantee provisions of this title.

=Title II: Coordination of Federal Activities in Geothermal Energy Exploration, Research, and Development= - Authorizes and directs the Secretary of Interior to coordinate the development and implementation of a national inventory of geothermal resources in the United States.

Authorizes and directs the Administrator of the National Aeronautics and Space Administration to transmit to the Secretary of Interior a proposal for the employment of space technologies and the services and facilities of NASA for inventorying geothermal resources.

Authorizes and directs the Atomic Energy Commission to: (1) conduct, encourage, and promote scientific research to develop effective, economical, and environmentally acceptable processes and equipment for the purpose of utilizing all forms of geothermal resources for the production of useful energy forms; (2) conduct engineering and technical work including the design, construction, and testing of pilot plants to develop and improve geothermal energy processes and plant design concepts to the point of demonstration on a commercial scale; (3) study methods for the recovery and marketing of byproducts resulting from the production of energy from geothermal resources; and (4) undertake engineering and economic studies to determine the potential for energy from geothermal resources to contribute to energy requirements on national and regional levels.

Authorizes the Commission to investigate, negotiate, and enter into cooperative agreements with non-Federal utilities, industries, and governmental entities for the construction, operation, and maintenance of demonstration developments for the production of electric or heat energy, water supplies, or minerals from geothermal resources.

Authorizes the Commission to investigate potential agreements for the cooperative development of major facilities to demonstrate the production of energy from geothermal resources.

Authorizes appropriations to the Secretary of the Interior, the AEC, and NASA to carry out the purposes of this Act.

Geothermal Energy Act - Title I: Loan Guarantee Program - Declares it to be the policy of the Congress to encourage the commercial development of means to produce energy from geothermal resources and to facilitate such development by authorizing the Secretary of the Interior to guarantee loans for such purposes.

Authorizes the Secretary of the Interior to guarantee loans made for the purposes of acquiring rights in geothermal resources and performing exploration, development, and construction and operation of facilities for the commercial production of energy from geothermal resources. Specifies the terms and conditions such loans must meet prior to guarantee.

Authorizes the Secretary to enter into contracts to pay the lenders the interest charges which become due and payable on the unpaid balance of any such loan if the Secretary finds that enumerated circumstances occur.

Establishes, in the Treasury of the United States, a Geothermal Resources Development Fund. Authorizes to be appropriated to the fund an amount not to exceed $50,000,000 annually, and such amounts as may be required for the administrative costs of carrying out the provisions of this title.

Title II: Coordination of Federal Activities in Geothermal Energy Exploration, Research, and Development - Directs the Secretary, acting through the Geological Survey, to: (1) carry out a plan for the orderly exploration of all forms of geothermal resources of the Federal lands; (2) conduct regional surveys that will lead to a national inventory of geothermal resources in the United States; (3) publish and make available maps, reports, and other documents developed from such exploration to facilitate the commercial development of geothermal resources; (4) make such recommendations for legislation; and, (5) participate with the Atomic Energy Commission, the National Aeronautics and Space Administration, and the National Science Foundation in research.

Enumerates the activities in which the Atomic Energy Commission is directed to participate in furtherance of the purposes of this Act. Directs the Commission to coordinate such activities with the Department of the Interior.

States the conditions precedent to entering into agreements under this Act. Authorizes the Commission to investigate potential agreements for the cooperative development of major facilities to demonstrate the production of energy from geothermal resources and to submit engineering and financial proposals to the Congress for consideration of authorization to proceed with implementation.

Authorizes to be appropriated to carry out the purposes of this title: (1) $10 million for fiscal years 1974, 1975 and 1976 to the Secretary of the Interior; (2) $35 million for fiscal years 1974, 1975 and 1976 to the Atomic Energy Commission; and (3) such amounts as may be required in fiscal years 1974, 1975 and 1976 to NASA.