GEOTHERMAL RESOURCES LEASE

Exhibit 10.7

[***] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS, HAS BEEN OMITTED FROM PUBLIC FILING PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT SUBMITTED TO THE U.S. SECURITIES AND EXCHANGE COMMISSION. THE OMITTED INFORMATION, WHICH HAS BEEN IDENTIFIED WITH THE SYMBOL “[***],” HAS BEEN FILED SEPARATELY WITH THE U.S. SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

GEOTHERMAL RESOURCES LEASE

(Minersville Land and Livestock–Surface Lands Retained by

Lessor)

THIS GEOTHERMAL RESOURCES LEASE (“Lease”), entered into this 25 ^th day of September, 2007, by and between MINERSVILLE LAND AND LIVESTOCK COMPANY, a Utah corporation (collectively, “Lessor”), and INTERMOUNTAIN RENEWABLE POWER, LLC, a Delaware limited liability company (“Lessee”).

1. INTEREST GRANTED:

The interest granted hereunder is in the geothermal resources estate, and Lessor shall retain the surface estate. In addition, the parties believe that the Lessor holds an undivided 75% interest in the geothermal resources estate, with the remaining 25% (the “25% Interest”) held by the successors and assigns of Superior Oil Company (per grant from Ronald G. Wilcox). Lessee shall be responsible for coordinating with the holder of the 25% Interest in leasing such interest. The Production Royalties payable under Section 3(b) shall be proportionately reduced to the extent that Lessor holds less than the full interest in the geothermal estate (for example, 75% of the [***] and [***] Production Royalties specified in Section 3(b) (i) ) . In the event Lessor re-acquires the 25% Interest, such interest shall be deemed to be leased to Lessee hereunder and the Production Royalties increased accordingly. In consideration of the covenants and agreements contained herein, Lessor hereby grants and leases to Lessee the exclusive right and privilege to drill for, extract, produce, remove, utilize, sell, and dispose of all forms of thermal energy and other associated geothermal resources including without limitation:

(1) all products of geothermal processes, including the natural heat of the earth, and the energy, in whatever form, including pressure, present in, resulting from, created by, or which may be extracted from that natural heat, directly or through a material medium together with indigenous steam, hot water and hot brines; (2) steam and other gases, hot water and hot brines resulting from water, gas, or other fluids, including water and steam naturally present in a geothermal system, artificially introduced into subsurface formations to serve as a heat transfer medium; (3) natural heat of the earth and the energy associated with that natural heat, and pressure; and (4) all dissolved or entrained minerals, substances or by-products (“Substances”) that may be obtained from the medium used to transfer that heat, but excluding hydrocarbons and helium (collectively “Geothermal Resources,” which includes Substances except as necessary to separately determine royalties as provided in Section 3),

in, on, under, adjacent to, or associated with those certain parcels of property (the “Premises”) consisting of approximately eleven thousand two hundred and ninety-four (11,294) acres, as more particularly described as follows :

All that certain real property consisting of approximately 11,294 acres located in Beaver County, State of Utah, more particularly described on Exhibit A attached hereto and incorporated herein by reference, including all interests in said Premises now owned or hereafter acquired, together with:

(a) Exploration . The exclusive right to conduct within the leased area geological and geophysical exploration for Geothermal Resources;

(b) Development and Operations . Subject to the approval of Lessor as to location, not to be unreasonably withheld, the right to construct or erect and to use, operate, and maintain on the Premises, together with ingress and egress thereupon, all wells, pumps, pipes, pipe lines, buildings, plants, sumps, brine pits, reservoirs, tanks, waterworks, pumping stations, roads, electric power generating plants, transmission lines, industrial facilities, telephone lines, and such other works and structures and to use so much of the surface of the land that may be reasonably necessary or convenient for the exploration, development, production, utilization, transportation, and processing of Geothermal Resources or for the full enjoyment of the rights granted by this Lease, subject to applicable laws and regulations;

(c) Water . The non-exclusive right to drill water wells, and the exclusive right to drill wells into Geothermal Resources that contain water, steam and brines, in accordance with Utah statutory laws within the Premises and to use the water produced therefrom for operations and activities hereunder, free of costs, provided that such drilling and development is conducted in such a way that they do not unreasonably interfere with Lessor’s activities on the Premises; and further that Lessor will use its best efforts to cooperate with Lessee to apply for, appropriate and use water produced from the Premises (or lands pooled or unitized therewith) in furtherance of developing and conducting operations on the Premises (or lands pooled or unitized therewith). Lessor and Lessee shall evaluate the possibility of providing some water from geothermal operations for use in livestock watering.

(d) Injection . The right, without the payment of royalties hereunder, to inject or reinject into the leased lands geothermal resources, condensates, gas, treated wastewater or other fluids to the extent that such resources, condensates and fluids are necessary or convenient for operation under this Lease in the recovery or processing of Geothermal Resources, including to maintain or increase pressure or production or to conduct tests.

(e) Directional Drilling . The right to locate a well or wells on the surface of said land and to directional or slant drill said well or wells into, under, across and through the Premises and into and under other lands in the vicinity of the Premises, together with the right to repair, re-drill, deepen, maintain, inject in, rework and operate or abandon such well or wells for the production of Geothermal Resources from such other lands together with the right to develop water from said land for any of Lessee’s operations; together with the right to construct, erect, maintain, use, operate, replace, and remove all power generation facilities, transmission facilities, pipe lines, telephone lines, tanks, machinery, and other facilities; together with all other rights necessary or convenient for Lessee’s operations under this subsection including rights of way for passage over and upon and across and ingress and egress to and from said Premises; together with the right and easement to continue to use such items, as well as rights of way and/or easements appurtenant thereto, so long as Lessee

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utilizes Geothermal Resources from such other land in the vicinity of the Premises, notwithstanding the expiration, termination or forfeiture of this Lease, until such use is permanently discontinued. Upon the written request of Lessee, Lessor agrees to provide separate easements or rights-of-ways, in form sufficient for recording in the applicable county real property records, to evidence such surface rights in this Section l(e). If the Lessor fails to provide such written easements within thirty (30) days of Lessee’s written request, Lessor authorizes Lessee to unilaterally prepare and execute such easements and record the same in the applicable county’s real property records. Should Lessee elect to unilaterally execute such easements, the nature, scope and duration of such easements as described in the executed document shall accurately and reasonably reflect the existing uses in relation to Lessee’s surface and underground operations on the Premises (or on lands pooled and unitized therewith).

2. TERM:

(a) Initial Term, As Extended . This Lease shall have a term of TEN (10) years from the date first set forth above (the “Initial Term”) and shall continue for so long thereafter as:

(i) Lessee is extracting or drilling for Geothermal Resources on the Premises (or lands pooled or unitized with the Premises), working with reasonable diligence, allowing not more than TWENTY-FOUR (24) months between the completion or abandonment of one site/well and the exploration and/or commencement of operations for the next;

(ii) Geothermal Resources are being produced or generated from the Premises (or lands pooled or unitized with the Premises) in commercial quantities or steps are being taken to develop the Premises in such a way as to produce or generate from the land commercial quantities;

(iii) Remedial Operations are being continuously conducted on the Premises (or lands pooled or unitized with the Premises);

(iv) Drilling operations, commercial production of Geothermal Resources, or Remedial Operations are suspended or excused under the Force Majeure or other provisions of this Lease; or

(vi) this Lease is otherwise extended by its terms.

“Remedial Operations” means reworking, redrilling, cleaning, testing, and the repair and replacement of wells and facilities for the production or use of Geothermal Resources. Remedial Operations shall be deemed continuous so long as such operations do not cease for a period of more than two (2) consecutive years. Production in “commercial quantities” shall mean production in such quantities of Geothermal Resources, produced, sold, or used, or capable of being produced, sold, or used, either from the Premises or lands pooled or unitized therewith, the value of which, after deducting Lessor’s royalty hereunder and Lessee’s normal operating costs will provide to Lessee a return of such costs.

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(b) Unit Contraction . In the event this Lease is committed to a unit or other pooling arrangement, and this Lease is later removed from such unit by contraction of the unit boundaries or any participating area while the Lease is in an extended term beyond the Initial Term or within five (5) years of the end of the Initial Term, then the Initial Term of this Lease shall be extended for a period of five (5) years from the date the Lease is removed from such unit or other pooling arrangement. In the event of an extension pursuant to this subsection (c), the Lessee is authorized to unilaterally execute and record a notice of extension of the Lease, to provide public notice of such extension.

3. RENTALS AND ROYALTIES:

(a) Initial Payment; Rentals . On the date hereof, and subject to confirmation of clear title to the Geothermal Resources, Lessor shall pay to Lessee the sum of [***]. On or before each anniversary date hereafter while the Lease is in force, Lessee agrees to pay to Lessor as rental for the next ensuing year the sum of [***] per acre; provided, however, that rentals paid to Lessor under this subsection shall apply toward or be credited to royalties payable or to become payable on actual production (if any) under Section 3(b) for any year such rentals are paid. To the extent a portion of the original acreage of this Lease is lost or surrendered by the Lessee, the Annual Rental shall be reduced proportionately.

(b) Production Royalties . Subject to Section 11 below, and subject to proportionate reduction as described in Section 1 and in Section 3(d), Lessee shall pay to Lessor a royalty out of the proceeds received by Lessee from the sale of Geothermal Resources or Substances produced from the Premises, or allocated to the Premises as provided in Sections 6 and/or 10(b) as follows:

(i) Power Generation . If Lessee utilizes Geothermal Resources to generate and sell electric power, a royalty of [***] of the gross proceeds of the sale of said electric power for the first [***] years from the first sale of electricity and [***] thereafter, in each case less Deductible Costs (as defined in Section 3(b) (vi));

(ii) Sale of Substances . If Lessee sells any Substances as such, a royalty of [***] of the gross proceeds of the sale of said Substances for the first [***] years from the first sale of Substances and [***] thereafter, in each case less Deductible Costs;

(iii) Sale of By-Products . If Lessee treats or processes or causes to be processed, any Substances and/or Geothermal Resources for the extraction or manufacture therefrom of any by-products, and sells any by-products, a gross royalty of [***] of the proceeds from the sale by Lessee of said by-products, less Deductible Costs;

(iv) Other Commercial . If Lessee uses Geothermal Resources and/or Substances at a commercial facility other than an electric power generating facility, a royalty of [***] of the net profits produced by such commercial operation, net profits being the proceeds generated by Lessee, less all associated costs to Lessee including but not limited to any plant, facility and/or operational costs and of any transmission or transportation to the point of use if used off the Premises or off of any area pooled or unitized with the Premises (the “Unit Area”), as the case may be.

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(v) Internal Use . Lessee may use, free of royalty, Substances, Geothermal Resources, electric power and by-products developed from the Premises for all operations hereunder (or operations within any Unit Area), and Lessee shall not be required to account to Lessor for or pay royalty on any Substances, Geothermal Resources, electric power or by-products reasonably lost or consumed in operations hereunder.

(vi) Deductible Costs . For purposes of Sections 3(b)(i)-(iii) above, “Deductible Costs” shall mean:

(A) any sales, excise or other taxes imposed on the sale of any said electric power, Substances, or by-products, as the case may be, so sold or which are required to be included in or added to the sales price thereof or paid by the seller; and

(B) any cost to Lessee of any transmission or transportation to the point of sale of any of said electric power, Substances or by-products so sold, if sold off the Premises or the Unit Area, as the case may be; and

(C) assuming Lessee does not use electricity generated from the geothermal plant(s) for such requirements, the reasonable and standard cost of any electricity purchased by Lessee from unaffiliated third parties to operate the geothermal well field pumps or serve other parasitic loads of the geothermal gathering field or the generating plant(s).

(vii) Payment . Lessee shall pay Lessor, on or before the last day of each and every calendar month, the above production royalties accrued and payable for the preceding calendar month (“Payment Date”), and shall deliver to Lessor a statement setting forth the basis for the determination of such royalty. Notwithstanding anything to the contrary, Lessor agrees that the Payment Date shall be adjusted to coincide with billing procedures set forth in any applicable power purchase agreements, whether monthly, bi-monthly, quarterly, or otherwise.

(c) Directional Drilling and Other Surface Use Rentals . If Lessee exercises the directional drilling rights granted in Section 1(e), or if Lessee is using part of the surface of the Premises for unit or other operations and the Lease is terminated or surrendered (including without limitation, in the event the Lease is committed to a unit but is later excluded from such unit by contraction of the unit or any participation area) Lessor shall not be entitled to any production royalties under Section 3(b), unless, and only to the extent that, such activity constitutes a commingling, pooling or unitization utilizing Geothermal Resources from the Premises under Section 6. In lieu of any other compensation, Lessee shall pay to Lessor an annual rental computed at the rate of [***] per acre for each surface acre of the Premises being exclusively occupied by Lessee pursuant to such grant under Section 1(e) and [***] per rod for any roads, utility lines, pipelines, or other linear items associated therewith.

(d) Proportionate Reduction . In the event Lessor at the time of making this Lease owns an interest in the leased Premises that is less than one hundred per cent of the total rights in the geothermal estate, then the rentals, royalties and other consideration

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accruing hereunder shall be paid to Lessor only in the same proportions which Lessor’s interest bears to a one hundred per cent interest in the leased Premises. Notwithstanding the foregoing, should Lessor hereafter acquire any additional right, title or interest in or to the leased Premises, it shall be subject to the provisions hereof to the same extent as if owned by the Lessor at the date hereof, and any increase in payments of money hereunder necessitated thereby shall commence with the payment next following receipt by Lessee of satisfactory evidence of Lessor’s acquisition of such additional interest.

4. TAXES AND ASSESSMENTS:

(a) Taxes and Improvements . Lessee shall pay all taxes levied and assessed against Lessee’s leasehold interest in the Premises. Lessee shall pay all taxes levied and assessed against all structures, improvements and personal property placed upon the Premises by Lessee. Lessor shall pay all taxes levied and assessed against the Premises as such and against any rights thereto not covered by the Lease and shall pay all taxes levied and assessed against all structures and improvements placed on the Premises by Lessor. Any increase in taxes arising from geothermal operations on the Premises shall be paid by Lessee.

(b) Severance Taxes on Lessor’s Royalties . Lessor agrees to pay any and all taxes assessed upon Lessor’s royalty proceeds for any Substances and/or Geothermal Resources produced and sold by Lessee from the Premises and ad valorem taxes on Substances and/or Geothermal Resources together with the same share of all severance, production, net proceeds and license taxes or other taxes or assessments levied or assessed on account of the production of Substances and/or Geothermal Resources from or allocated to the Premises, and to pay all of any other taxes assessed against the Premises, whether the same are assessed to Lessor or Lessee or otherwise. Lessor shall pay all of its tax obligations within thirty (30) days of when due and shall provide Lessee, upon request, with evidence of such payment. Lessor grants Lessee the right, but not the obligation, to pay any of Lessor’s tax obligations hereunder, and to offset the amount of such payments made on Lessor’s behalf against any amounts due to Lessor under this Lease, with interest at [***].

5. PROTECTION OF SURFACE; LAWS; LIENS; EQUIPMENT

(a) Protection of Surface; Compensation for Damage . Lessee agrees to conduct its activities in a good and workmanlike manner and use reasonable care at all times in all of Lessee’s operations on the Premises to prevent injury or damage to cattle, livestock, buildings, water rights, water diversion works, ditches, tanks and water wells or other property of the Lessor located thereon; and Lessee agrees to repair, mitigate or pay the Lessor the fair market value (as determined by an independent third-party appraiser) for all damages to the cattle, crops, buildings, livestock, fences, water rights, water diversions, ditches, tanks, water, water wells and other property of the Lessor situated on the surface of the Premises resulting from Lessee’s operations on the Premises. Lessee also agrees that all damages to pipe and equipment caused by cattle shall be the responsibility of Lessee.

(b) Compliance with Laws . Lessor and Lessee each agree that they will conduct all activities and operations associated with the Premises and with this Lease at all times in accordance with applicable federal, state and local laws, rules and regulations.

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(c) Liens . All labor to be performed and material to be furnished in the operations under this Lease shall be at the sole cost and expense of Lessee, and Lessee shall hold Lessor free and harmless from liability thereunder. Lessee and Lessor shall each keep the Premises fully protected against any and all liens of every character arising from or connected with their individual operations on the Premises. Lessor agrees not to permit any mortgage or other lien to be placed on the property that would affect or purport to affect or supersede Lessee’s interest under this Lease. Lessor acknowledges and agrees that Lessee, in order to pursue its activities hereunder may utilize various project, equipment and other financing options and as part of such financings Lessee may assign its interests under this Lease (whether for security purposes or as a full and complete assignment). To the extent the Premises are currently encumbered by a mortgage, deed of trust, or other lien created by Lessor, Lessor shall use its best efforts to obtain a subordination, in recordable form, of such encumbrance to this Lease.

(d) Reclamation . Within six (6) months after abandonment of any well, including those abandonments resulting from termination of this Lease, Lessee shall remove all machinery, material, and structures used in connection with said well and not used in its other operations, if any, on the Premises, and shall fill in and level off all excavations, pits, or other alterations to the surface of the Premises caused in connection with said well, and, insofar as practical, shall, restore the Premises and the means of ingress and egress in compliance with all requirements of applicable reclamation laws and regulations, except reasonable wear and tear, acts of nature and conditions beyond the control of Lessee.

(e) Equipment and Improvements . Lessor agrees that Lessee shall retain ownership of, and can remove at any time, any and all improvements, equipment, fixtures and property of any kind brought onto or attached or affixed to the Premises, including all well casings, pipes, power generation equipment, buildings, transmission lines and all other equipment or property of any kind, regardless of whether such property is considered realty or personalty for state law or other purposes.

6. COMMINGLING, POOLING, AND UNITIZATION:

(a) Commingling . Lessee shall have the right to commingle (for purposes of storing, transporting, handling, unitizing, selling or processing) Geothermal Resources produced or extracted from the Premises (and lands pooled, unitized or combined therewith), with similar substances produced or extracted from other lands or units. In the event of such commingling, Lessee shall meter, gauge, or measure, according to prevalent industry standards, the production from the Premises at the well head, or from the unit or units including the leased land or other units or lands, as applicable, and compute and pay Lessor’s royalty attributable to Lessor’s land on the basis of such production as so determined or allocated.

(b) Pooling and Unitization . Lessee may, without notice to or consent from Lessor, as a recurring right for drilling, development or operating purposes, pool, unitize, or otherwise combine all or part of the Premises into a unit (whether federal or voluntary contractual unit) with any other land or lands (whether held by Lessee or others), whether or not adjacent or contiguous,

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which Lessee desires to develop or operate (singly or in combination with others) as a unit. The execution by Lessee of any unit agreement, unit operating agreement or other documents necessary to such pooling or unitization shall be binding on the Premises and Lessor’s current and future interests therein. Lessee shall provide Lessor courtesy notice of any pooling or unitization of the Premises. Any well (whether or not Lessee’s well) commenced, drilled, drilling and/or producing or being capable of producing in any part of such unit shall for all purposes of this Lease be deemed a well commenced, drilled, drilling and/or producing on the Premises, and the Lessee shall have the same rights and obligations with respect thereto and the drilling and producing operations upon the lands from time to time included within any such unit as Lessee would have if such lands constituted the Premises leased hereunder; provided, however, that notwithstanding this or any other provision or provisions of this Lease to the contrary:

(i) Production as to which a royalty is payable from any such wells or wells drilled upon any such unit, whether located on the Premises or other lands, shall be allocated to the Premises in the proportion that the acreage of the leased land in such unit bears to the total acreage of such unit. Such allocated portion thereof shall for all purposes be considered as having been produced from the Premises, and the royalty, payable under this Lease with respect to the leased land in such unit shall be payable only upon that proportion of production so allocated, and

(ii) If taxes of any kind are levied or assessed (other than taxes on the surface and on Lessor’s improvements), any portion of which is chargeable to Lessor under the provisions of this Lease, then the share of such taxes to be borne by Lessor shall be in proportion to the share of the production from such unit allocated to the Premises.

(iii) Lessor hereby grants Lessee (or the consents to the assignment of such rights from Lessee to any unit operator) the right to use of the surface of the Premises in support of unit operations, including all the surface uses enumerated in Section 1 above. In the event the Premises, or any portion thereof, are later removed from the unit by any contraction of the Unit Area, all such existing surface uses of the Premises in support of unit operations shall continue in force and effect, and Lessor agrees to provide Lessee or the unit operator with written easements, rights-of-way, licenses or such other acceptable surface use grants, in recordable form, to evidence such existing surface uses in support of unit operations. If the Lessor fails to provide such written easements within thirty (30) days of Lessee’s written request, Lessor authorizes Lessee to unilaterally prepare and execute such easements and record the same in the applicable county’s real property records. Should Lessee elect to unilaterally execute such easements, the nature, scope and duration of such easements as described in the executed document shall accurately and reasonably reflect the existing uses in relation to Lessee’s surface and underground operations on the Premises (or on lands pooled and unitized therewith).

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7. RESERVATIONS TO LESSOR:

The following rights (to the extent owned by Lessor) are reserved to Lessor, provided such rights and activities do not interfere with Lessee’s exploration, development, production or other operations, activities or rights hereunder on the Premises or any Unit Area:

(i) Surface Use - the right to conduct ranching operations, or sell or otherwise dispose of the surface of the Premises (subject to this Lease) in a lawful manner. Any specific restrictions on the prospective use of the Premises by Lessee, as a result of specific surface needs of the Lessor, may be set forth in an Appendix to this Lease.

(ii) Mineral Rights - the right to extract minerals, hydrocarbons, and helium (other than Substances) from the Premises, subject to the following covenants and restrictions:

Notwithstanding the reservation of mineral rights to the Lessor, Lessor and Lessee acknowledge that Lessee shall make substantial investments in exploring for and developing geothermal resources on the Premises (or Unit Area). “Lessor hereby covenants and agrees, on behalf of itself, its successor