changes to the prevailing tariff regime or in the identity and creditworthiness of our power purchasers. In Nicaragua, there is potential labor unrest and strengthening of labor unions, which may adversely affect our Momotombo project. In Kenya, the new government elected in 2002 is making an effort to deliver on campaign promises to reduce the price of electricity and is applying pressure on independent power producers, such as our Olkaria III project, to lower their tariffs. In addition, Kenya's new government is considering a further restructuring and privatization of the electricity industry and may divide Kenya Power & Lighting Co. Ltd., the power purchaser for our Olkaria III project, into separate entities and then privatize one or more of such resulting entities. A material tariff reduction or any break-up and potential privatization of Kenya Power & Lighting Co. Ltd. may adversely affect our Olkaria III project. We have recently held discussions with the Kenyan government and Kenya Power & Lighting Co. Ltd. regarding, among other things, the construction of Phase II of the Olkaria III project in Kenya and the provision of certain collateral and government support. We must notify Kenya Power & Lighting Co. Ltd., by April 17, 2005, whether we will proceed to construct Phase II of the Olkaria III project and, if we notify Kenya Power & Lighting Co. Ltd. that we will not proceed with such construction, then the portion of the current power purchase agreement applicable to Phase II of the Olkaria III project will be terminated (but the current portion applicable to Phase I will be unaffected). If we fail to provide such notification we will be required to construct Phase II and reach commercial operations by May 31, 2007 in order to avoid the application of financial penalties, or at the latest by April 17, 2008 in order to avoid termination of the entire power purchase agreement. In addition, if we do not proceed with the construction of Phase II, we may lose some or all of our investment relating to Phase II, which is approximately $22.2 million.

Although we generally obtain political risk insurance in connection with our foreign projects, such political risk insurance does not mitigate all of the above-mentioned risks. In addition, insurance proceeds received pursuant to our political risk insurance policies, where applicable, may not be adequate to cover all losses sustained as a result of any covered risks and may at times be pledged in favor of the lenders to a project as collateral. Also, insurance may not be available in the future with the scope of coverage and in amounts of coverage adequate to insure against such risks and disturbances.

Our foreign projects and foreign manufacturing operations expose us to risks related to fluctuations in currency rates, which may reduce our profits from such projects and operations.

Risks attributable to fluctuations in currency exchange rates can arise when any of our foreign subsidiaries borrow funds or incur operating or other expenses in one type of currency but receive revenues in another. In such cases, an adverse change in exchange rates can reduce such subsidiary's ability to meet its debt service obligations, reduce the amount of cash and income we receive from such foreign subsidiary or increase such subsidiary's overall expenses. In addition, the imposition by foreign governments of restrictions on the transfer of foreign currency abroad or restrictions on the conversion of local currency into foreign currency would have an adverse effect on the operations of our foreign projects and foreign manufacturing operations and may limit or diminish the amount of cash and income that we receive from such foreign projects and operations.

A significant portion of our net revenue is attributed to payments made by power purchasers under power purchase agreements. The failure of any such power purchaser to perform its obligations under the relevant power purchase agreement or the loss of a power purchase agreement due to a default would reduce our net income and could materially and adversely affect our business, financial condition, future results and cash flow.

A significant portion of our net revenue is attributed to revenues derived from power purchasers under the relevant power purchase agreements. Southern California Edison Company, Hawaii Electric Light Company, PNOC-Energy Development Corporation and Sierra Pacific Power Company have accounted for 48.3%, 9.2%, 6.2% and 5.6% of our pro forma revenues, respectively, for the fiscal year ended December 31, 2003. Neither we nor any of our affiliates make any representations as to the financial condition or creditworthiness of any purchaser under a power purchase agreement and nothing in this prospectus should be construed as such a representation.

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There is a risk that any one or more of the power purchasers may not fulfill their respective payment obligations under their power purchase agreements. For example, as a result of the energy crisis in California, Southern California Edison Company withheld payments it owed under various of its power purchase agreements with a number of power generators (such as the Ormesa, Heber 1, Heber 2, and Mammoth projects) payable for certain energy delivered between November 2000 and March 2001 under such power purchase agreements until March 2002. In the case of our Ormesa project (which we acquired in April 2002), the payment withheld by Southern California Edison Company totaled $21.2 million. If any of the power purchasers fails to meet its payment obligations under its power purchase agreements, it could materially and adversely affect our business, financial condition, future results and cash flow.

In connection with the power purchase agreements for the Ormesa project, Southern California Edison Company has expressed its intent not to pay the contract rate for the power supplied by the GEM 2 and GEM  3 plants to the Ormesa project for auxiliary purposes. We have commenced discussions with Southern California Edison Company to resolve the dispute. In the interim period, Southern California Edison Company has tentatively agreed to pay a lower fixed price for such power. We cannot evaluate the potential long-term financial impact of a failure to reach a resolution with Southern California Edison Company, among other things because the current contract rates will fluctuate as of May 2007, however, financial loss at the reduced price paid by Southern California Edison Company for our fiscal year ended December 31, 2005 may be in the range of $1 million.

Seasonal variations may cause significant fluctuations in our cash flows, which may cause the market price of our common stock to fall in certain periods.

Our results of operations are subject to seasonal variations. This is primarily because some of our domestic projects receive higher capacity payments under the relevant power purchase agreements during the summer months and due to the generally higher short run avoided costs in effect during the summer months. Some of our other projects may experience reduced generation during warm periods due to the lower heat differential between the geothermal fluid and the ambient surroundings. Such seasonal variations could materially and adversely affect our business, financial condition, future results and cash flow. If our operating results fall below the public's or analysts' expectations in some future period or periods, the market price of our common stock will likely fall in such period or periods.

Pursuant to the terms of some of our power purchase agreements with investor-owned electric utilities in states that have renewable portfolio standards, the failure to supply the contracted capacity thereunder may result in the imposition of penalties.

Pursuant to the terms of the Galena, Desert Peak 2 and Desert Peak 3 power purchase agreements that we have entered into and under which we will sell electricity from the Galena, Desert Peak 2 and Desert Peak 3 projects that are currently under development and construction, we may be required to make payments to the relevant power purchaser in an amount equal to such purchaser's replacement costs for renewable energy relating to any shortfall amount of renewable energy that we do not provide as required under the power purchase agreement and which such power purchaser is forced to obtain from an alternate source. In addition, we may be required to make payments to the relevant power purchaser in an amount equal to its replacement costs relating to any renewable energy credits we do not provide as required under the relevant power purchase agreement. We may also be required to pay liquidated damages if certain minimum performance requirements are not met under certain of our power purchase agreements, all of which could materially and adversely affect our business, financial condition, future results and cash flow. The minimum performance requirements are described in "Description of Certain Material Agreements—Project-related Agreements." With respect to certain of our power purchase agreements, we may also be required to pay liquidated damages to our power purchaser if the relevant project does not maintain availability of at least 85% during applicable peak periods. The maximum aggregate amount of such liquidated damages for the Steamboat 2 and Steamboat 3 power purchase agreements would be approximately $1.5 million for each project. The Puna project was not in compliance with the minimum performance

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requirements of its power purchase agreement at the time we acquired such project and is currently not in compliance with such requirements. Such non-compliance has resulted in the imposition of sanctions that have reduced, and as long as such non-compliance continues to exist, will continue to reduce, the aggregate amount of revenues payable to us from the power purchaser by approximately $6,000 per month. Further, the temperature of the geothermal resource at our Heber 1 project has declined from the date on which the project commenced operations and, as a result, the project currently operates at a level that is close to the minimum performance requirements set forth in the project's power purchase agreement. If we fail to upgrade the project's facilities and the project's performance deteriorates below the minimum capacity requirements, we will be obligated to pay a one-time penalty to the power purchaser of approximately $500,000 per each MW of reduced capacity.

The short run avoided costs for our power purchasers may decline, which would reduce our project revenues and could materially and adversely affect our business, financial condition, future results and cash flow.

Under the power purchase agreements for our projects in California, the price that Southern California Edison Company pays for energy is based upon its short run avoided costs, which are the incremental costs that it would have incurred had it generated the relevant electrical energy itself or purchased such energy from others. Under settlement agreements between Southern California Edison Company and a number of Qualifying Facility power generators in California, including our subsidiaries, the energy price component payable by Southern California Edison Company has been fixed through April 2007, and thereafter will be based on Southern California Edison Company's short run avoided costs, as determined by the California Public Utilities Commission, which we refer to as CPUC. These short run avoided costs are made available by Southern California Edison Company to the public and may vary substantially on a monthly basis, based primarily on gas prices and other factors. The levels of short run avoided cost prices paid by Southern California Edison Company may decline following the expiration date of the settlement agreements, which in turn would reduce our project revenues derived from Southern California Edison Company under our power purchase agreements with it and could materially and adversely affect our business, financial condition, future results and cash flow.

In addition, under certain of the power purchase agreements for our projects in Nevada, the price that Sierra Pacific Power Company pays for energy and capacity is based upon its short run avoided costs. These short run avoided costs, and in turn the rates payable by Sierra Pacific Power Company, may decline, which in turn would reduce the aggregate amount of project revenues recovered by our Nevada projects pursuant to the relevant power purchase agreements. Such a decrease in project revenues could adversely affect our business, financial condition, future results and cash flow.

In response to an order issued by a California State Court of Appeal, the CPUC has commenced an administrative proceeding in order to address short run avoided cost pricing for Qualifying Facilities for the period spanning from December 2000 to March 2001. The court directed the CPUC to modify short run avoided cost pricing on a retroactive basis to the extent that the CPUC determined that short run avoided cost prices were not sufficiently "accurate" or "correct." If the short run avoided cost prices charged during the period in question were determined by the CPUC not to be "accurate" or "correct," retroactive price adjustments could be required for any of our Qualifying Facilities in California whose payments are tied to short run avoided cost pricing, including the Heber 1, Mammoth and Ormesa projects. Currently, it is not possible to predict the outcome of such proceeding, however, any retroactive price adjustment required to be made in relation to any of our projects may require such projects to make refund payments or charge less for future sales, which could materially and adversely affect our business, financial condition, future results and cash flow.

If any of our domestic projects loses its Qualifying Facility status under PURPA, or if amendments to PURPA are enacted that substantially reduce the benefits currently afforded to our Qualifying Facilities, our domestic operations could be adversely affected.

The operations of most of our domestic projects are subject to, and benefit from, the Public Utility Regulatory Policies Act of 1978, as amended, which we refer to as PURPA, are subject to

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limited provisions of the Federal Power Act, which we refer to as FPA, and are potentially subject to the provisions of various other energy laws and regulations, including the Public Utility Holding Company Act of 1935, as amended, which we refer to as PUHCA, other provisions of the FPA and certain state and local laws and regulations regarding rates and financial and organizational requirements for electric utilities.

Qualifying Facility status under PURPA exempts our projects from PUHCA, most of the provisions of the FPA, and certain state laws concerning rates and the financial and organizational regulation of electric utilities. If any of our domestic projects in which we have an interest loses its Qualifying Facility status and no regulatory exemptions apply, or if amendments to PURPA are enacted that substantially reduce the benefits currently afforded Qualifying Facilities, our operations could be adversely affected.

In the event that one of our domestic projects loses its Qualifying Facility status, such project and we would become subject to PUHCA and such project would become subject to the full scope of the FPA and applicable state regulations unless an exemption or waiver applies, such as "exempt wholesale generator" ("EWG", as defined under PUHCA) status or "utility geothermal small power production facility" (as defined under PURPA regulations) status, for such project. The application of PUHCA and such other regulations to our projects would require our operations to comply with an increasingly complex regulatory regime that may be costly and greatly reduce our operational flexibility. In the unlikely event that none of the PUHCA exemptions or waivers are available, we could become a public utility holding company under PUHCA, which could be deemed to occur prospectively or retroactively to the date that any of our projects lost its Qualifying Facility status. In addition, our other domestic projects could lose Qualifying Facility status because our interests in such projects could be considered to be electric utility holding company interests for purposes of the 50% limit on ownership of Qualifying Facilities by electric utilities or electric utility holding companies. As a result of such loss of Qualifying Facility status, and in the absence of an applicable exemption or waiver, the Federal Energy Regulatory Commission, which we refer to as FERC, or relevant state regulators, whichever has jurisdiction, may order partial refunds of past amounts paid by the relevant power purchaser or order a reduction of the rate pursuant to the power purchase agreement prospectively, or both, and thus could cause the loss of some or all of our revenues payable pursuant to the related power purchase agreement, result in significant liability for refunds of past amounts paid, or otherwise impair the value of our projects.

A loss of Qualifying Facility status also could permit the power purchaser, pursuant to the terms of the particular power purchase agreement, to cease taking and paying for electricity from the relevant project or, consistent with FERC precedent, to seek refunds of past amounts paid. This could cause the loss of some or all of our revenues payable pursuant to the related power purchase agreement, result in significant liability for refunds of past amounts paid, or otherwise impair the value of our project. If a power purchaser were to cease taking and paying for electricity or seek to obtain refunds of past amounts paid, there can be no assurance that the costs incurred in connection with the project could be recovered through sales to other purchasers or that we would have sufficient funds to make such payments. In addition, the loss of Qualifying Facility status would be an event of default under the financing arrangements currently in place for some of our projects, which would enable the lenders to exercise their remedies and enforce the liens on the relevant project.

The United States Congress is considering proposed legislation that would amend PURPA by limiting the mandatory purchase obligations of power purchasers under new power purchase agreements. The enactment of such legislation could adversely affect our new projects or enhancements of existing projects that do not have a current power purchase agreement.

An adverse FERC ruling related to the use by a project of power generated from another Qualifying Facility for auxiliary purposes may adversely affect our operations and financial results.

According to a recent FERC decision, a geothermal Qualifying Facility that obtains electricity for the operation of its reinjection pumps from an electric utility must reduce its net capacity available for sale by an equivalent amount. However, if the electricity for reinjection pumping is provided by

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Qualifying Facilities that are cogeneration or small power production facilities, no reduction in net capacity is required. Two of our projects obtain electricity from an electric utility for the operation of their reinjection pumps. In the past, these projects did not reduce their net capacity available for sale by an equivalent amount. The application of FERC's recent ruling to such projects could have an adverse effect on their revenues received from power sales and their operations and financial condition.

Our financial performance is significantly dependent on the successful operation of our projects, which is subject to changes in the legal and regulatory environment affecting our projects.

All of our projects are subject to extensive regulation and, therefore, changes in applicable laws or regulations, or interpretations of those laws and regulations, could result in increased compliance costs, the need for additional capital expenditures or the reduction of certain benefits currently available to our projects. The structure of federal and state energy regulation is currently, and may continue to be, subject to challenges, modifications, the imposition of additional regulatory requirements, and restructuring proposals. We and our power purchasers may not be able to obtain all regulatory approvals that may be required in the future, or any necessary modifications to existing regulatory approvals, or maintain all required regulatory approvals. In addition, the cost of operation and maintenance and the operating performance of geothermal power plants may be adversely affected by changes in certain laws and regulations, including tax laws.

The federal government also encourages production of electricity from geothermal resources through certain tax subsidies. We are permitted to claim in our consolidated federal tax returns approximately 10% of the construction cost of each new geothermal power plant as a credit against our consolidated federal income taxes. We are also permitted to deduct, as a depreciation expense on our consolidated federal tax returns, up to 95% of the cost of the power plant over five years on an accelerated basis, which results in more of the cost being deducted in the first few years than during the remainder of the depreciation period. In addition, we have the ability to obtain value from these tax incentives through lease financing transactions even when we are not in a position to use them directly. Any reduction in such tax incentives or any restrictions on such lease financing transactions would materially and adversely affect our business, financial condition, future results and cash flow.

Any such changes could significantly increase the regulatory-related compliance and other expenses incurred by the projects and could significantly reduce or entirely eliminate the revenues generated by one or more of the projects, which in turn would reduce our net income and could materially and adversely affect our business, financial condition, future results and cash flow.

The costs of compliance with environmental laws, which currently are significant, may increase in the future and could materially and adversely affect our business, financial condition, future results and cash flow and any non-compliance with such laws or regulations may result in the imposition of liabilities which could materially and adversely affect our business, financial condition, future results and cash flow.

Our projects are required to comply with numerous domestic and foreign federal, regional, state and local statutory and regulatory environmental standards and to maintain numerous environmental permits and governmental approvals required for construction and/or operation. Some of the environmental permits and governmental approvals that have been issued to the projects contain conditions and restrictions, including restrictions or limits on emissions and discharges of pollutants and contaminants, or may have limited terms. If we fail to satisfy these conditions or comply with these restrictions, or with any statutory or regulatory environmental standards, we may become subject to regulatory enforcement action and the operation of the projects could be adversely affected or be subject to fines, penalties or additional costs. In addition, we may not be able to renew, maintain or obtain all environmental permits and governmental approvals required for the continued operation or further development of the projects, as a result of which the operation of the projects may be limited or suspended. Environmental laws, ordinances and regulations affecting us can be subject to change and such change could result in increased compliance costs, the need for additional capital expenditures, or otherwise adversely affect us.

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We could be exposed to significant liability for violations of hazardous substances laws because of the use or presence of such substances at our projects.

Our projects are subject to numerous domestic and foreign federal, regional, state and local statutory and regulatory standards relating to the use, storage and disposal of hazardous substances. We use isobutane, isopentane, industrial lubricants and other substances at our projects which are or could become classified as hazardous substances. If any hazardous substances are found to have been released into the environment at or by the projects, we could become liable for the investigation and removal of those substances, regardless of their source and time of release. If we fail to comply with these laws, ordinances or regulations (or any change thereto), we could be subject to civil or criminal liability, the imposition of liens or fines, and large expenditures to bring the projects into compliance. Furthermore, in the United States, we can be held liable for the cleanup of releases of hazardous substances at other locations where we arranged for disposal of those substances, even if we did not cause the release at that location. The cost of any remediation activities in connection with a spill or other release of such substances could be significant.

We believe that at one time there may have been a gas station located on the Mammoth project site, but because of significant surface disturbance and construction since that time further physical evaluation of the former gas station site has been impractical. There may be soil or groundwater contamination and related liability exposure of which we are unaware related to this site which may be significant and may adversely and materially affect our operations and revenues.

We may not be able to successfully integrate companies that we have acquired or which we may acquire in the future, which could materially and adversely affect our business, financial condition, future results and cash flow.

We recently acquired our Heber 1, Heber 2, Mammoth, Steamboat 2/3, Steamboat Hills and Puna projects. Our strategy is to continue to expand in the future, including through acquisitions. Integrating acquisitions is often costly, and we may not be able to successfully integrate our acquired companies with our existing operations without substantial costs, delays or other adverse operational or financial consequences. Integrating our acquired companies involves a number of risks that could materially and adversely affect our business, including:

•	failure of the acquired companies to achieve the results we expect;

•	inability to retain key personnel of the acquired companies;

•	risks associated with unanticipated events or liabilities; and

•	the difficulty of establishing and maintaining uniform standards, controls, procedures and policies, including accounting controls and procedures.

If any of our acquired companies suffers customer dissatisfaction or performance problems, the same could adversely affect the reputation of our group of companies and could materially and adversely affect our business, financial condition, future results and cash flow.

The power generation industry is characterized by intense competition, and we encounter competition from electric utilities, other power producers, and power marketers that could materially and adversely affect our business, financial condition, future results and cash flow.

The power generation industry is characterized by intense competition from electric utilities, other power producers and power marketers. In recent years, there has been increasing competition in the sale of electricity, in part due to excess capacity in a number of U.S. markets and an emphasis on short-term or "spot" markets, and competition has contributed to a reduction in electricity prices. For the most part, we expect that power purchasers interested in long-term arrangements with a capacity price component will engage in "competitive bid" solicitations to satisfy new capacity demands. This competition could adversely affect our ability to obtain power purchase agreements and the price paid for electricity by the relevant power purchasers. There is also increasing competition between electric utilities, particularly in California where the CPUC has launched an initiative designed to give all

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electricity consumers the ability to choose between competing suppliers of electricity. This competition has put pressure on electric utilities to lower their costs, including the cost of purchased electricity, and increasing competition in the future will put further pressure on power purchasers to reduce the prices at which they purchase electricity from us.

The existence of a prolonged force majeure event or a forced outage affecting a project could reduce our net income and materially and adversely affect our business, financial condition, future results and cash flow.

If a project experiences a force majeure event, our subsidiary owning that project would be excused from its obligations under the relevant power purchase agreement. However, the relevant power purchaser may not be required to make any capacity and/or energy payments with respect to the affected project or plant so long as the force majeure event continues and, pursuant to certain of our power purchase agreements, will have the right to prematurely terminate the power purchase agreement. Additionally, to the extent that a forced outage has occurred, the relevant power purchaser may not be required to make any capacity and/or energy payments to the affected project, and if as a result the project fails to attain certain performance requirements under certain of our power purchase agreements, the purchaser may have the right to permanently reduce the contract capacity (and, correspondingly, the amount of capacity payments due pursuant to such agreements in the future), seek refunds of certain past capacity payments, and/or prematurely terminate the power purchase agreement. As a consequence, we may not receive any net revenues from the affected project or plant other than the proceeds from any business interruption insurance that applies to the force majeure event or forced outage after the relevant waiting period and may incur significant liabilities in respect of past amounts required to be refunded. Accordingly, our business, financial condition, future results and cash flows could be materially and adversely affected.

The existence of a force majeure event or a forced outage affecting the transmission system of the Imperial Irrigation District could reduce our net income and materially and adversely affect our business, financial condition, future results and cash flow.

If the transmission system of the Imperial Irrigation District experiences a force majeure event or a forced outage which prevents it from transmitting the electricity from the Heber 1 and Heber 2 projects or the Ormesa project to the relevant power purchaser, the relevant power purchaser would not be required to make energy payments for such non-delivered electricity and may not be required to make any capacity payments with respect to the affected project so long as such force majeure event or forced outage continues. Our pro forma revenues in 2003 from the projects utilizing the Imperial Irrigation District transmission system were approximately $98.6 million. The impact of such force majeure would depend on the duration thereof, with longer outages resulting in greater revenue loss.

Some of our leases will terminate if we do not extract geothermal resources in "commercial quantities," thus requiring us to enter into new leases or secure rights to alternate geothermal resources, none of which may be available on terms as favorable to us as any such terminated lease, if at all.

Most of our geothermal resource leases are for a fixed primary term, and then continue for so long as geothermal resources are extracted in "commercial quantities" or pursuant to other terms of extension. The land covered by some of our leases is undeveloped and has not yet produced geothermal resources in "commercial quantities." Leases that cover land which remains undeveloped and does not produce, or does not continue to produce, geothermal resources in commercial quantities and leases that we allow to expire, will terminate. In the event that a lease is terminated and we determine that we will need that lease once the applicable project is operating, we would need to enter into one or more new leases with the owner(s) of the premises that are the subject of the terminated lease(s) in order to develop geothermal resources from or inject geothermal resources into such premises or secure rights to alternate geothermal resources or lands suitable for injection, all of which may not be possible or could result in increased cost to us, which could materially and adversely affect our business, financial condition, future results and cash flow.

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Our Bureau of Land Management leases may be terminated if we fail to comply with any of the provisions of the Geothermal Steam Act of 1970 or if we fail to comply with the terms or stipulations of such leases, which may materially and adversely affect our business and operations.

Pursuant to the terms of our Bureau of Land Management (which we refer to as BLM) leases, we are required to conduct our operations on BLM-leased land in a workmanlike manner and in accordance with all applicable laws and BLM directives and to take all mitigating actions required by the BLM to protect the surface of and the environment surrounding the relevant land. Additionally, certain BLM leases contain additional requirements, some of which relate to the mitigation or avoidance of disturbance of any antiquities, cultural values or threatened or endangered plants or animals, the payment of royalties for timber and the imposition of certain restrictions on residential development on the leased land. In the event of a default under any BLM lease, or the failure to comply with such requirements, or any non-compliance with any of the provisions of the Geothermal Steam Act of 1970 or regulations issued thereunder, the BLM may, 30 days after notice of default is provided to our relevant project subsidiary, suspend operations until the requested action is taken or terminate the lease, either of which could materially and adversely affect our business, financial condition, future results and cash flows.

Some of our leases (or subleases) could terminate if the lessor (or sublessor) under any such lease (or sublease) defaults on any debt secured by the relevant property, thus terminating our rights to access the underlying geothermal resources at that location.

The fee interest in the land which is the subject of each of our leases (or subleases) may currently be or may become subject to encumbrances securing loans from third party lenders to the lessor (or sublessor). Our rights as lessee (or sublessee) under such leases (or subleases) are or may be subject and subordinate to the rights of any such lender. Accordingly, a default by the lessor (or sublessor) under any such loan could result in a foreclosure on the underlying fee interest in the property and thereby terminate our leasehold interest and result in the shutdown of the project located on the relevant property and/or terminate our right of access to the underlying geothermal resources required for our operations.

In addition, a default by a sublessor under its lease with the owner of the property that is the subject of our sublease could result in the termination of such lease and thereby terminate our sublease interest and our right to access the underlying geothermal resources required for our operations.

We depend on key personnel for the success of our business.

Our success is largely dependent on the skills, experience and efforts of our senior management team and other key personnel. In particular, our success depends on the continued efforts of Lucien Bronicki, Yehudit Bronicki, Hezy Ram, Nadav Amir and other key employees. The loss of the services of any key employee could materially harm our business, financial condition, future results and cash flow. Although to date we have been successful in retaining the services of senior management by entering into employment agreements with such members of senior management, such members of our senior management may terminate their employment agreements without cause and with notice periods ranging from 120 to 180 days. We may also not be able to locate or employ on acceptable terms qualified replacements for our senior management or key employees if their services were no longer available.

Our projects have generally been financed through a combination of parent company loans and limited- or non-recourse project finance debt. If our project subsidiaries default on their obligations under such limited- or non-recourse debt, we may be required to make certain payments to the relevant debt holders and if the collateral supporting such leveraged financing structures is foreclosed upon, we may lose certain of our projects.

Our projects have generally been financed using a combination of parent company loans and limited- or non-recourse project finance debt. Non-recourse project finance debt refers to debt that is

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repaid solely from the project's revenues and is secured by the project's physical assets, major contracts, cash accounts and, in many cases, our ownership interest in the project subsidiary. Limited- recourse project finance debt refers to our additional agreement, as part of the financing of a project, to provide limited financial support for the project subsidiary in the form of limited guarantees, indemnities, capital contributions and agreements to pay certain debt service deficiencies. If our project subsidiaries default on their obligations under the relevant debt documents, creditors of a limited-recourse project financing will have direct recourse to us, to the extent of our limited-recourse obligations, which may require us to use distributions received by us from other projects, as well as other sources of cash available to us, in order to satisfy such obligations. In addition, if our project subsidiaries default on their obligations under the relevant debt documents and the creditors foreclose on the relevant collateral, we may lose our ownership interest in the relevant project subsidiary or our project subsidiary owning the project would only retain an interest in the physical assets, if any, remaining after all debts and obligations were paid in full.

Changes in costs and technology may significantly impact our business by making our power plants and products less competitive.

A basic premise of our business model is that generating baseload power at central geothermal power plants achieves economies of scale and produces electricity at a competitive price. However, traditional coal-fired systems and gas-fired systems may under certain economic conditions produce electricity at lower average prices than our geothermal plants. In addition, there are other technologies that can produce electricity, most notably fossil fuel power systems, hydroelectric systems, fuel cells, microturbines, windmills and photovoltaic (solar) cells. Some of these alternative technologies currently produce electricity at a higher average price than our geothermal plants; however, research and development activities are ongoing to seek improvements in such alternate technologies and their cost of producing electricity is gradually declining. It is possible that advances will further reduce the cost of alternate methods of power generation to a level that is equal to or below that of most geothermal power generation technologies. If this were to happen, the competitive advantage of our projects may be significantly impaired.

Our expectations regarding the market potential for the development of recovered energy-based power generation may not materialize, and as a result we may not derive any significant revenues from this line of business.

We have identified recovered energy-based power generation as a significant market opportunity for us. Demand for our recovered energy-based power generation units may not materialize or grow at the levels that we expect. We currently face competition in this market from manufacturers of conventional steam turbines and may face competition from other related technologies in the future. If this market does not materialize at the levels that we expect, such failure may materially and adversely affect our business, financial condition, future results and cash flow.

Our intellectual property rights may not be adequate to protect our business.

Our intellectual property rights may not be adequate to protect our business. While we occasionally file patent applications, patents may not be issued on the basis of such applications or, if patents are issued, they may not be sufficiently broad to protect our technology. In addition, any patents issued to us or for which we have use rights may be challenged, invalidated or circumvented.

In order to safeguard our unpatented proprietary know-how, trade secrets and technology, we rely primarily upon trade secret protection and non-disclosure provisions in agreements with employees and others having access to confidential information. These measures may not adequately protect us from disclosure or misappropriation of our proprietary information.

Even if we adequately protect our intellectual property rights, litigation may be necessary to enforce these rights, which could result in substantial costs to us and a substantial diversion of management attention. Also, while we have attempted to ensure that our technology and the operation of our business do not infringe other parties' patents and proprietary rights, our competitors

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or other parties may assert that certain aspects of our business or technology may be covered by patents held by them. Infringement or other intellectual property claims, regardless of merit or ultimate outcome, can be expensive and time-consuming and can divert management's attention from our core business.

We are subject to risks associated with a changing economic and political environment, which may adversely affect our financial stability or the financial stability of our counterparties.

The risk of terrorist attacks in the United States or elsewhere continues to remain a potential source of disruption to the nation's economy and financial markets in general. The availability and cost of capital for our business and that of our competitors has been adversely affected by the bankruptcy of Enron Corp. and events related to the California electric market crisis. Additionally, the recent rise in fuel costs may make it more expensive for our customers to operate their businesses. These events could constrain the capital available to our industry and could adversely affect our financial stability and the financial stability of our counterparties in transactions.

Possible fluctuations in the cost of raw materials may materially and adversely affect our business, financial condition, future results and cash flow.

Our manufacturing operations are dependent on the supply of various raw materials, including primarily steel and aluminium, and on the supply of various industrial equipment components that we use. We currently obtain all such materials and equipment at prevailing market prices. We are not dependent on any one supplier and do not have any long-term agreements with any of our suppliers. Future cost increases of such raw materials and equipment, to the extent not otherwise passed along to our customers, could adversely affect our profit margins.

Conditions in Israel, where the majority of our senior management and all of our production and manufacturing facilities are located, may adversely affect our operations and may limit our ability to produce and sell our products or manage our projects.

Operations in Israel accounted for approximately 61.3%, 56.3%, and 51.0% of our operating expenses in fiscal year 2001, fiscal year 2002 and fiscal year 2003, respectively. Political, economic and security conditions in Israel directly affect our operations. Since the establishment of the State of Israel in 1948, a number of armed conflicts have taken place between Israel and its Arab neighbors, and the continued state of hostility, varying in degree and intensity, has led to security and economic problems for Israel. Since October 2000, there has been a significant increase in violence, primarily in the West Bank and Gaza Strip, and more recently Israel has experienced a significant increase in terrorist incidents within its borders. As a result, negotiations between Israel and representatives of the Palestinian Authority have been sporadic and have failed to result in peace. We could be adversely affected by hostilities involving Israel, the interruption or curtailment of trade between Israel and its trading partners, or a significant downturn in the economic or financial condition of Israel. In addition, the sale of products manufactured in Israel may be adversely affected in certain countries by restrictive laws, policies or practices directed toward Israel or companies having operations in Israel.

In addition, some of our employees in Israel are subject to being called upon to perform military service in Israel, and their absence may have an adverse effect upon our operations. Generally, unless exempt, male adult citizens of Israel under the age of 41 are obligated to perform up to 36 days of military reserve duty annually. Additionally, all such citizens are subject to being called to active duty at any time under emergency circumstances.

These events and conditions could disrupt our operations in Israel, which could materially harm our business, financial condition, future results and cash flow.

Failure to comply with certain conditions and restrictions associated with tax benefits provided to Ormat Systems by the Government of Israel as an "approved enterprise" may require us to refund such tax benefits and pay future taxes in Israel at higher rates.

Our subsidiary, Ormat Systems, has received "approved enterprise" status under Israel's Law for Encouragement of Capital Investments, 1959, with respect to two of its investment programs. As an

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approved enterprise, our subsidiary is exempt from Israeli income taxes with respect to revenues derived from the approved investment program for a period of two years commencing on the year it first generates profits from the approved investment program, and thereafter such revenues are subject to reduced Israeli income tax rates of 25% for an additional five years. These benefits are subject to certain conditions set forth in the certificate of approval from Israel's Investment Center, which include, among other things, a requirement that Ormat Systems comply with Israeli intellectual property law, that all transactions between Ormat Systems and our affiliates be at arms length, and that there will be no change in control of, on a cumulative basis, more than 49% of Ormat Systems' capital stock (including by way of a public or private offering) without the prior written approval of the Investment Center. If Ormat Systems does not comply with these conditions, in whole or in part, it would be required to refund the amount of tax benefits (as adjusted by the Israeli consumer price index and for accrued interest) and would no longer benefit from the reduced Israeli tax rates, which could have an adverse effect on our financial condition, future results and cash flow. If Ormat Systems distributes dividends out of revenues derived during the tax exemption period from the approved investment program, it will be subject, in the year in which such dividend is paid, to Israeli income tax on the distributed dividend.

If our parent defaults on its lease agreement with the Israel Land Administration, or is involved in a bankruptcy or similar proceeding, our rights and remedies under certain agreements pursuant to which we acquired our products business and pursuant to which we sublease our land and manufacturing facilities from our parent may be adversely affected.

We acquired our business relating to the manufacture and sale of products for electricity generation and related services from our parent, Ormat Industries. In connection with that acquisition, we entered into a sublease with Ormat Industries for the lease of the land and facilities where our manufacturing and production operations are conducted and where our Israeli offices are located. Under the terms of our parent's lease agreement with the Israel Land Administration, any sublease for a period of more than five years may require the prior approval of the Israel Land Administration. As a result, the initial term of our sublease with Ormat Industries is for a period of four years and eleven months, extendable to twenty-five years (which includes the initial term) should our parent obtain the approval of the Israel Land Administration, to the extent necessary. If such an approval is required and our parent fails to obtain the Israel Land Administration's approval, our sublease will terminate on June 1, 2009, at which time we will have to renegotiate the terms of a new sublease. We may not be successful in reaching an agreement with our parent as to the terms of a new sublease or in obtaining such sublease on favorable terms, both of which would adversely affect our manufacturing activities and our financial position. Additionally, if our parent were to breach its obligations to the Israel Land Administration under its lease agreement, the Israel Land Administration could terminate the lease agreement and, consequently, our sublease would terminate as well.

As part of the acquisition described in the preceding paragraph, we also entered into a patent license agreement with Ormat Industries, pursuant to which we were granted an exclusive license for certain patents and trademarks relating to certain technologies that are used in our business. If a bankruptcy case were commenced by or against our parent, it is possible that performance of all or part of the agreements entered into in connection with such acquisition (including the lease of land and facilities described above) could be stayed by the bankruptcy court in Israel or rejected by a liquidator appointed pursuant to the Bankruptcy Ordinance in Israel and thus not be enforceable. Any of these events could have a material and adverse effect on our business, financial condition, future results and cash flow.

We are a holding company and our revenues depend substantially on the performance of our subsidiaries and the projects they operate, most of which are subject to restrictions and taxation on dividends and distributions.

We are a holding company whose primary assets are our ownership of the equity interests in our subsidiaries. We conduct no other business and, as a result, we depend entirely upon our subsidiaries' earnings and cash flow.

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The agreements pursuant to which most of our subsidiaries have incurred debt restrict the ability of these subsidiaries to pay dividends, make distributions or otherwise transfer funds to us prior to the satisfaction of other obligations, including the payment of operating expenses, debt service and replenishment or maintenance of cash reserves. In the case of some of our projects, such as the Mammoth project, there may be certain additional restrictions on dividend distributions pursuant to our agreements with our partners. Further, if we elect to receive distributions of earnings from our foreign operations, we may incur United States taxes on account of such distributions, net of any available foreign tax credits. In all of the foreign countries where our existing projects are located, dividend payments to us are also subject to withholding taxes. Each of the events described above may reduce or eliminate the aggregate amount of revenues we can receive from our subsidiaries.

Risks Relating to this Offering

Our controlling stockholders may take actions that conflict with your interests.

Immediately following this offering,         % of our common stock will be held by Ormat Industries, Ltd. (        % if the underwriters exercise their over-allotment option in full), which is controlled by Bronicki Investments Ltd. Bronicki Investments Ltd. is a privately held Israeli company and is controlled by Lucien and Yehudit Bronicki. Because of these holdings, our parent company and its controlling stockholders will be able to exercise control over all matters requiring stockholder approval, including the election of directors, amendment of our certificate of incorporation and approval of significant corporate transactions, and they will have significant control over our management and policies. The directors elected by these stockholders will be able to significantly influence decisions affecting our capital structure. This control may have the effect of delaying or preventing changes in control or changes in management, or limiting the ability of our other stockholders to approve transactions that they may deem to be in their best interest. For example, our controlling stockholders will be able to control the sale or other disposition of our products business to another entity or the transfer of such business outside of the State of Israel, as such action requires the affirmative vote of at least 75% of our outstanding shares.

Some of our directors that also hold positions with our parent may have conflicts of interest with respect to matters involving both companies.

Two of our three directors are directors and/or officers of Ormat Industries. These directors will have fiduciary duties to both companies and may have conflicts of interest on matters affecting both us and our parent and in some circumstances may have interests adverse to our interests. Our Chairman, Director and Chief Technology Officer, Mr. Bronicki, will continue to be Chairman of our parent following the offering. In addition, our Chief Executive Officer and Director, Mrs. Bronicki, will continue to be the Chief Executive Officer of our parent following the offering.

There has been no prior market for our common stock and an active trading market may not develop.

Prior to this offering, there has been no public market for our common stock. An active trading market may not develop following the closing of this offering or, if developed, may not be sustained. The lack of an active market may impair your ability to sell your shares of common stock at the time you wish to sell them or at a price that you consider reasonable. The lack of an active market may also reduce the fair market value and increase the volatility of your shares of common stock. An inactive market may also impair our ability to raise capital by selling shares of common stock and may impair our ability to acquire other companies or technologies by using our shares of common stock as consideration.

The price of our common stock may fluctuate substantially and your investment may decline in value.

The initial public offering price for the shares of our common stock sold in this offering will be determined by negotiation between the representative of the underwriters and us. This price may not reflect the market price of our common stock following this offering. In addition, the market price of our common stock is likely to be highly volatile and may fluctuate substantially due to many factors, including:

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•	actual or anticipated fluctuations in our results of operations including as a result of seasonal variations in our electricity-based revenues;

•	variance in our financial performance from the expectations of market analysts;

•	conditions and trends in the end markets we serve and changes in the estimation of the size and growth rate of these markets;

•	announcements of significant contracts by us or our competitors;

•	changes in our pricing policies or the pricing policies of our competitors;

•	loss of one or more of our significant customers;

•	legislation;

•	changes in market valuation or earnings of our competitors;

•	the trading volume of our common stock; and

•	general economic conditions.

In addition, the stock market in general, and the New York Stock Exchange and the market for energy companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of particular companies affected. These broad market and industry factors may materially harm the market price of our common stock, regardless of our operating performance. In the past, following periods of volatility in the market price of a company's securities, securities class-action litigation has often been instituted against that company. Such litigation, if instituted against us, could result in substantial costs and a diversion of management's attention and resources, which could materially harm our business, financial condition, future results and cash flow.

Our management team may invest or spend the proceeds of this offering in ways with which you may not agree or in ways that may not yield a positive return.

Presently, anticipated uses of the proceeds to us of this offering include funding business growth and expansion, providing additional working capital, and for other general corporate purposes. We cannot specify with certainty how we will use the net proceeds of this offering. Accordingly, our management will have considerable discretion in the application of these proceeds, and you will not have the opportunity to assess whether these proceeds are being used appropriately. These proceeds may be used for corporate purposes that do not increase our operating results or market value. Until the net proceeds are used, they may be placed in investments that do not produce income or that lose value.

Future sales of our common stock may depress our share price.

After this offering, we will have                  shares of common stock outstanding. The                  shares sold in this offering (or                  shares if the underwriters' over-allotment option is exercised in full) will be freely tradable without restriction or further registration under federal securities laws unless purchased by our affiliates. The remaining shares of common stock outstanding after this offering are subject to lock-up agreements, will be available for sale in the public market beginning 180 days after the date of this prospectus, and will be subject to certain volume limitations under Rule 144 of the Securities Act of 1933, as amended. Lehman Brothers Inc. may waive the lock-up provisions in its sole discretion.

Sales of substantial amounts of our common stock in the public market following this offering, or the perception that these sales may occur, could cause the market price of our common stock to decline. At or prior to the closing of this offering, we will enter into a registration rights agreement with Ormat Industries. See "Certain Relationships and Related Transactions" for more information.

This offering will cause substantial dilution in the net tangible book value of your shares of common stock.

The initial public offering price of our common stock is considerably more than the net tangible book value per share of our outstanding common stock. Accordingly, investors purchasing shares of

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common stock in this offering will contribute         % of the total amount invested to fund our company, but will own only         % of the shares of common stock outstanding after this offering. To the extent outstanding stock options are exercised, there will be further dilution to new investors. See "Dilution" for more information.

Provisions in our charter documents and Delaware law may delay or prevent acquisition of us, which could adversely affect the value of our common stock.

Our restated certificate of incorporation and our bylaws contain provisions that could make it harder for a third party to acquire us without the consent of our board of directors. These provisions do not permit actions by our stockholders by written consent. In addition, these provisions include procedural requirements relating to stockholder meetings and stockholder proposals that could make stockholder actions more difficult. Our board of directors will be classified into three classes of directors serving staggered, three-year terms and may be removed only for cause. Any vacancy on the board of directors may be filled only by the vote of the majority of directors then in office. Our board of directors has the right to issue preferred stock without stockholder approval, which could be used to institute a "poison pill" that would work to dilute the stock ownership of a potential hostile acquirer, effectively preventing acquisitions that have not been approved by our board of directors. Delaware law also imposes some restrictions on mergers and other business combinations between us and any holder of 15% or more of our outstanding common stock. Although we believe these provisions provide for an opportunity to receive a higher bid by requiring potential acquirers to negotiate with our board of directors, these provisions apply even if the offer may be considered beneficial by some stockholders.

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