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Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
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Appendix C—
Summary of Recent Studies

Several studies in recent years have addressed various aspects of energy-related research and development (R&D). The major conclusions of these studies are abstracted in this appendix to summarize current thinking on critical issues facing R&D and the deployment of renewable energy technologies.

The Yergin Report

A task force was established by the U.S. Department of Energy's (DOE's) Secretary of Energy's Advisory Board in 1994 to review DOE's R&D programs in terms of DOE's strategic goals and policy priorities, as well as national needs. The findings from the Final Report of the Task Force on Strategic Energy Research & Developments (DOE, 1995) that are relevant to the present study are listed below.

Key Findings

  1. Energy is fundamental to the functioning of industrial societies. Global energy demand, arising mainly from developing economies, is expected to grow by about 40 percent in the next 15 years.

  2. Energy R&D, both public and private, has greatly contributed to successes in the past 15 years—on both the supply side and the demand side. R&D also contributes significantly to higher standards of living by creating new products, new processes, new jobs, and new opportunities. The contributions of DOE's R&D have also been significant.

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
  1. The federal government should not fund R&D that the private sector can and should support on its own. Federal support for R&D is most strongly justified when the R&D serves national interests that would not be satisfied by market action alone.

  2. ''Cost-sharing" with industry leverages federal R&D spending, introduces market relevance into federal R&D decision making, and accelerates the R&D process and transfer of results into the economy and the marketplace.

  3. The traditional division between "basic" and "applied" research is breaking down. The complexity of research problems requires interactivity between the two. The traditional paradigm is being replaced by "concurrent R&D."

  4. Although DOE's management of its energy R&D programs has improved in some respects over the years, it could be much more efficient and effective and could deliver more value to American taxpayers.

  5. Effective public investment in energy R&D requires continuity—including much longer funding commitments than the yearly congressional budget cycles. This will require new, innovative financing mechanisms.

Key Recommendations

  1. DOE should benchmark its own R&D management practices against "best practices" in the private sector and elsewhere in the government.

  2. DOE should adopt "best practices," insofar as practicable, and seek appropriate changes in legislation where best practices are legally restricted or precluded.

  3. DOE should develop an integrated strategic plan and process for energy R&D and use this process to determine funding priorities and manage a diverse energy R&D investment portfolio. The portfolio should include the following elements:

    • a balance of basic research and applied R&D (including industry cofunded demonstrations)

    • near-term and long-term R&D to provide continuing return on investment and to contribute to the health and vitality of domestic energy industries

    • a continuing commitment to supporting energy efficiency and renewable energy

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

THE FIVE-LABORATORY STUDY

Five DOE national laboratories conducted a study to quantify the potential reductions of carbon emissions in the United States by (at least) the year 2010 from energy-efficient and low-carbon technologies (EERE, 1997). Scenarios of U.S. Carbon Reductions: Potential Impacts of Energy Technologies by 2010 and Beyond focused on how different sectors of the economy might respond to programs for reducing carbon emissions. Several options for the (electric) utility sector were assessed, and three conclusions emerged from the analysis:

  • A vigorous national commitment to develop and deploy energy-efficient, low-carbon technologies has the potential to restrain growth in U.S. energy consumption and reduce carbon emissions by 2010 to near 1997 levels (for energy) and 1990 levels (for carbon).

  • Implementation of suggested carbon-reduction scenarios could yield energy savings roughly equal to or more than cost. Only technologies thought to be cost effective by 2010 were studied. Specific policies, political feasibilities, and pathways to achieve the analyzed scenarios were not included.

  • The next generation of energy-efficient, low-carbon technologies could enable an aggressive pace of carbon reduction over the next quarter century.

The study found that renewable energy technologies have great potential for reducing carbon emissions, but mostly beyond the 2010 focus of the study. Renewable energy technologies were considered to be in transition from "advanced technologies" to mainstream "technologies of choice" that could play a market role as the cost of generating electricity from these technologies declines. In the analysis of the impact of renewable energy technologies in 2010, a policy of a $50/metric ton cost on carbon emissions was assumed.

Cofiring with biomass was considered to have the technical potential to replace at least 8 gigawatts (GW) of U.S. coal-based generating capacity by 2010, and perhaps 26 GW by 2020. Demonstrations have shown that few modifications to burners and feed-intake systems would be required to cofire coal with up to 15 percent biomass. A dedicated feedstock supply system for fast-growing sources of biomass, such as willow trees, poplar trees, and switch grasses, would have to be developed for biomass to reach a potential of 8-12 GW by 2010, with a reduction in carbon emissions of 16-24 million tons carbon (MtC).

The most important R&D for biomass are in the areas of gasification/conversion systems and feedstock production. Gasification is a demonstration technology for converting solid biomass material to a gas that can be cleaned and burned in a combustion turbine or used in a combined-cycle plant; gasification could double the efficiency of current biomass power. New biomass species

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

could improve crop yields and lower feedstock costs. The development of wholetree processing methods would lower handling and processing costs.

Wind power technology has been progressing rapidly since 1980, and 1,800 MW of electricity are now produced in the United States. Costs were projected to decline to below the median price for electricity by 2010, with a range of 5 GW (simple extrapolation of growth) to 50 GW (assuming competitive pricing and policies emphasizing control of carbon emissions) of capacity from Class 5 and 6 sites. In this scenario, carbon reductions could be 6-20 MtC. Grid connectivity on this scale may be a problem because of the intermittency of the load.

Wind turbine design is a critical area for R&D to improve materials, increase efficiencies, and lengthen operating lifetimes. Engineering processes must also be improved. Improvements in turbine blade interfaces, with modeling of interactions, could minimize material utilization and extend blade life. Improved direct-drive generators and power electronics should yield higher power conversion efficiencies, perhaps eliminating the need for a mechanical gearbox in the drive train. Better resource characterization of wind prospecting and prediction could help with locating and siting projects.

Hydropower supplied about 10 percent of electricity and constituted 84 percent of renewable energy generation at the time of the study. Hydroelectric technology for utility-scale operations was considered mature, with progress being made to mitigate adverse environmental effects (but not greenhouse gas emissions), such as fish kills, erosion, and water pollution. Three types of hydropower facilities are in operation: dams with storage reservoirs; run-of-river systems without storage reservoirs; and pumped storage projects. Although pumped storage is not a renewable energy technology, it has the potential to reduce greenhouse gas emissions. Further expansion of hydropower capacity may be limited because of relicensing issues and environmental mitigation regulations. Net additions by 2010 are likely to be in the 10-16 GW range, with the potential to reduce carbon emissions by 3-5 MtC.

Costs for solar photovoltaics are currently significantly higher than for other renewable energy technologies, but sales and applications of systems are growing. Off-grid applications for village power are one important growth area. Another is building-integrated photovoltaics, in which solar panels are incorporated into the exterior surfaces of buildings. Thus, grid power would be displaced at the end point of the delivery system where the value is greatest, and photovoltaics peak power output would generally coincide with peak electricity demand. By 2010, photovoltaic installations may have the capacity to supply from 1-7 GW of electricity (based on incentives) and to reduce carbon emissions by 1-2 MtC. With technological advances, costs are expected to be substantially lower than present costs. More progress could be made in the development of photovoltaic power products and systems, as well as improvements in balance-of-systems components, such as power conditioners and controllers.

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

Geothermal power-generation technologies that produce electricity directly by thermal energy to a steam turbine or via heat transfer to a working fluid that drives a steam turbine were considered fairly mature. Approximately 3 GW of geothermal capacity is currently installed in the United States, with the potential for another 5 GW by 2010. The major problem is locating and characterizing the size and longevity of geothermal reservoirs. By 2020, improvements in drilling technology, seismic data-gathering techniques, and better computer modeling should make location and assessment of geothermal resources more efficient.

Solar thermal electric technologies use mirrors to concentrate reflected sunlight, thus creating a high-temperature source that can be used with a heat engine to generate electricity. There are three types of solar thermal power systems: parabolic troughs (large fields of reflectors heat a fluid in a receiver pipe located along the focal line of the reflector); solar thermal power towers (mirrors reflect sunlight to a thermal receiver atop a tower); and dish/engines (parabolic mirrors in a dish reflect sunlight onto a Stirling engine at the focal point of the dish). By 2010, up to 2 GW of solar thermal capacity will be operational, reducing carbon emissions by up to 1 MtC.

THE ELEVEN-LABORATORY STUDY

In 1997, 11 U.S. national laboratories completed a study of ways to reduce greenhouse gas emissions without inhibiting economic growth. Technology Opportunities to Reduce U.S. Greenhouse Gas Emissions (DOE, 1997), known as the Eleven-Laboratory Study (11-Lab), undertook to answer the following questions:

  • Which technologies can be improved through R&D that are not now deployed or used extensively?

  • Which new technologies could be developed in the future with reasonable effort and cost?

  • What kind of R&D program would bring about these results?

The major findings relevant to renewable energy technologies are summarized below.

Renewable energy pathways using energy from sunlight, wind, rivers, and oceans, heat from the planet, and biomass all have the potential to reduce greenhouse gas emissions by displacing fossil-fueled electricity generation or petroleum transportation fuels. In the power sector alone, renewable energies would be capable of reducing carbon emissions by about 70 MtC per year. The costs of renewable energy technologies are decreasing to the point that commercialization is a real possibility for early in the twenty-first century and are already competitive in certain niche markets.

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

Biomass as a cofired fuel with coal, gasified to replace natural gas, or as a stand-alone fuel has the potential to reduce fossil-fuel-fired electric power generation. R&D challenges that must be overcome are emissions of nitrogen oxides, ash chemistry, and associated operational problems.

Wind energy systems are competitive (on a levelized cost basis) with current power-generation systems. Most states have sites with high-quality wind resources and, if this technology were fully developed, carbon emissions could be significantly reduced before 2010. The next steps toward increasing market penetration are improving the design and reliability of turbines and methods of improving generation at sites via hybridization with other power technologies or new storage technologies.

Hydropower currently accounts for 10 percent of U.S. power generation, but prospects for further development of hydropower resources are not good. Concerns about impacts on fish and downstream water quality will have to be addressed and the cost-effectiveness of retrofitting demonstrated.

Solar photovoltaic technology using semiconductor-based cells to convert sunlight to electricity can work on a variety of scales. Annual growth of the market is 15 percent to 20 percent. The technology works especially well in offgrid applications, but costs are currently too high for bulk power generation. By 2010, photovoltaics could compete for peak power shaving opportunities (when demand for electrical capacity results in high electricity prices) and by 2020, for daytime electric power opportunities. Much research has yet to be done on materials and processes as a basis for advanced photovoltaic cell design and engineering.

Geothermal energy technologies use thermal energy from the earth to produce electricity or heat for industrial processes. Hydrothermal reservoirs produce about 2,100 megawatts electric (MWe) annually in the United States. Direct use of geothermal energy accounts for 400 megawatts thermal (MWt), and geothermal heat pump systems (using the earth as a heat sink for heating or air conditioning) contribute another 4,000 MWt in energy and are growing at about 25 percent per year. Currently, only a small portion of the huge geothermal resource can be used economically, but further engineering and reservoir research could double the production of electricity.

Solar thermal technologies, which concentrate sunlight to generate electricity, have been successfully demonstrated in nine commercial plants that provide 354 MW of electricity in California. Relatively conventional technology could add hundreds of megawatts of peaking power by 2005; further R&D will be necessary for bulk power generation by 2020.

Meeting the goals described in the 11-Lab report will require both incremental improvements and breakthroughs via basic and applied research. Strategic public/private alliances will be the best approach to developing and deploying most technologies for the reduction of greenhouse gases. Public/private strategic alliances will help maximize innovations by bringing together stakeholders

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

capable of overcoming scientific, technical, and commercial challenges. This report describes the reductions in carbon emissions that could result from an accelerated R&D program but does not describe collateral benefits of complementary deployment programs or policies to stimulate markets for these technologies. The most cost-effective approach would be science and technology combined with deployment programs and supporting policies.

The report concluded that a national investment in a technology R&D program over the next three decades would provide a portfolio of technologies that could significantly reduce emissions of greenhouse gases over the next three decades and beyond. A strategic plan that includes deployment policies to complement R&D will be necessary for success. Plans should reflect the economic and technological implications of deploying these technologies. Hence, the development of a technology strategy for mitigating climate change was the recommended next step. The development process should include a review of technology policy options to complement technology development options and a detailed plan for supporting implementation that addresses technology goals, R&D program plans, policies that support deployment, and fiscal resources. Development of this agenda should be a collaborative effort between government, industry, business, and the scientific communities.

PCAST I

In November 1997, the President's Committee of Advisors on Science and Technology (PCAST) completed a study, Federal Energy Research and Development Challenges of the Twenty-First Century, that focused on major challenges for a range of energy technologies (PCAST, 1997). The following discussion summarizes the findings and conclusions related to renewable energy technologies.

The primary challenge facing renewable technologies is relatively high unit costs, but progress on that front is being made. The cost of energy from wind power and photovoltaics has decreased about tenfold. Much of the market growth for renewable energy sources is expected to come from developing countries because the small scale and modularity of these technologies is suited to their needs. The panel concluded that R&D spending for renewable energy should be significantly increased. Suggestions were also laid out for improving the efficiency of wind power and photovoltaic systems, as well as the following time-defined technological goals:

  1. For wind systems, reduce the cost of generating electricity by 2005 by 50 percent so as to be competitive with fossil-based power generation in a restructured electricity industry.

  2. Pursue R&D in solar photovoltaics to reduce the cost of photovoltaic systems to $3,000/kW in five years; to $1,500/kW in 2010; to $1,000/kW

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

in 2020. R&D should also focus on balance-of-systems issues and advanced materials.

  1. Strengthen R&D for solar thermal technologies, such as parabolic dish and heliostat/central-receiver technology with high-temperature storage. Develop high-temperature receivers combined with gas turbine-based power. The goal is to make solar-only power competitive with fossil fueled power by 2015.

  2. In the next 10 years, commercialize advanced, energy-efficient biopower generation technologies employing gas turbines and fuel cells integrated with biomass gasifiers to exploit the advantages of biomass over coal as a feedstock for gasification.

  3. Continue work on hydrothermal systems and reactivate R&D on advanced concepts giving a high priority to high-grade hot dry rock geothermal technology (which has the potential to provide heat and baseload electricity in most areas of the United States).

  4. R&D on hydrogen-using and hydrogen-producing technologies should be supported. R&D on hydrogen-using technologies should be coordinated with proton-exchange membrane fuel-cell vehicle development by DOE. Working with DOE's Office of Fossil Energy program, R&D in hydrogen production should be prioritized to optimize the production of hydrogen from fossil fuels and the sequestration of carbon dioxide separated out in the production process.

  5. R&D for a new generation of hydropower turbines should focus on turbines that are less damaging to fish and aquatic ecosystems. By deploying these new technologies at existing dams and in new low-head, run-ofriver facilities, as much as 50,000 MW could be added by the year 2030.

  6. Resource assessment, international programs and analysis, and other crosscutting programs should be strongly supported. Additional R&D should focus on energy storage, electric systems, and systems integration.

Other general recommendations included more coordination and networking across the applied R&D "stovepipes" and with the Office of Science. In fact, one of the suggestions was that up to 5 percent of each applied R&D budget be reserved for collaborative, strategically driven, basic research activities with matching funding from, and supervision by, the Office of Science.

PCAST II

In June 1999, PCAST issued a second report, Powerful Partnerships: The Federal Role in International Cooperation on Energy Innovation , which is known as PCAST II (PCAST, 1999). The panel reviewed the U.S. role in international energy innovation and the roles of the public and private sectors in these activities. The panel concluded that energy initiatives have a window of opportunity

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

for attracting private sector capital for energy generation for economic development, as well as for addressing public-good issues globally. The energy technologies and infrastructures developed over the next few decades will have a strong impact on energy costs and end-use efficiencies, greenhouse gas emissions, air pollution, and a range of other factors for most of the next century. The globalization of innovation capacities and tightening constraints on spending for domestic R&D contribute to the attractiveness of international cooperation for developing energy technologies. International cooperation would also enhance the ability of U.S. energy companies to enter some of the largest markets for these new technologies. Energy-related global environmental problems and risks could also be lessened. The panel made the following observations related to energy R&D:

  • Accelerated innovation in energy technology can increase the pace and decrease the cost of the adoption of technologies that can improve the health and safety of the environment.

  • Innovations in energy are necessary to lower the energy intensity of economic activity, reduce emissions from energy activities, reduce the costs of delivering energy in environmentally sustainable ways, and increase energy options.

The panel cited the following reasons for U.S. participation in international energy projects:

  • The pace would be increased and the cost lowered of U.S. acquisition of innovations for domestic use.

  • U.S. firms would gain access to large overseas markets for innovative energy technologies.

  • The global dimensions of energy challenges would be addressed by accelerated development and deployment of innovations worldwide.

Continued government involvement in energy innovations would serve many needs that transcend private interests (e.g., social, macroeconomic, environmental, and international security concerns). Therefore, the panel recommended that government initiatives be structured to encourage, catalyze, and complement, rather than replace, corresponding activities in the private sector.

Specific opportunities for cooperation identified in the study were initiatives for the development of renewable energy technologies and fossil fuel decarbonization. The panel recommended that a broad-based renewable energy cluster organization be established to accelerate the development and deployment of renewable energy technologies, especially to meet energy needs in rural areas of the developing world. The establishment of a fossil-fuel decarbonization and carbon sequestration cluster was recommended as a multinational collaborative effort to develop technologies that would use fossil fuels economically in ways

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×

that resulted in near-zero life-cycle emissions of carbon dioxide. Expansion of the Vision 21 Program at the DOE Office of Fossil Energy was suggested, as well as the development of technologies to make hydrogen from carbonaceous feedstocks and to recover by-product carbon dioxide for safe disposal.

REFERENCES

DOE (U.S. Department of Energy). 1995. Final Report of the Task Force on Strategic Energy Research and Development. Washington, D.C.: Secretary of Energy Advisory Board, U.S. Department of Energy.

DOE. 1997. Technology Opportunities to Reduce U.S. Greenhouse Gas Emissions. Washington, D.C.: U.S. Department of Energy (October). Also available on line at: http://www.ornl.gov/climate_change


EERE (Office of Energy Efficiency and Renewable Energy). 1997. Scenarios of U.S. Carbon Reductions: Potential Impacts of Energy Technologies by 2010 and Beyond. Washington, D.C.: U.S. Department of Energy.


PCAST (President's Committee of Advisors on Science and Technology). 1997. Federal Energy Research and Development for the Twenty-First Century. Washington, D.C.: Executive Office of the President.

PCAST. 1999. Powerful Partnerships: The Federal Role in International Cooperation on Energy Innovation. Washington, D.C.: Executive Office of the President.

Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
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Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
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Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
Page 115
Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
Page 116
Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
Page 117
Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
Page 118
Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
Page 119
Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
Page 120
Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
Page 121
Suggested Citation:"Appendix C: Summary of Recent Studies." National Research Council. 2000. Renewable Power Pathways: A Review of the U.S. Department of Energy's Renewable Energy Programs. Washington, DC: The National Academies Press. doi: 10.17226/9843.
×
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Renewable Power Pathways is the result of a study by the National Research Council (NRC) Committee for the Programmatic Review of the Office of Power Technologies (OPT) review of the U.S. Department of Energy's (DOE) Office of Power Technologies and its research and development (R&D) programs. The OPT, which is part of the Office of Energy Efficiency and Renewable Energy, conducts R&D programs for the production of electricity from renewable energy sources. Some of these programs are focused on photovoltaic, wind, solar, thermal, geothermal, biopower, and hydroelectric energy technologies; others are focused on energy storage, electric transmission (including superconductivity), and hydrogen technologies. A recent modest initiative is focused on distributed power-generation technologies. This report reviews the activities of each of OPT's programs and makes recommendations for OPT as a whole and major recommendations for individual OPT programs.

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