MAIN POINTS
  • Concentrating solar power (CSP) can achieve gigaton scale by 2020 for an investment of $2.24 trillion.
  • Solar resources are abundant in the U.S. and globally to meet new energy demand; CSP is ideally situated to remote, high-isolation desert areas, so new transmission build-out is needed to bring CSP to high-population areas.
  • Solar thermal systems with storage can provide consistent power and thus are attractive relative to intermittent power sources, e.g., solar photovoltaics and wind.
  • Tested technology has been supplying cost-competitive solar thermal power in southern California for the past 20 years.
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Concentrating solar power (CSP) is a renewable generation technology that uses mirrors or lenses to concentrate the sun's rays to heat a fluid, e.g., water, which produces steam to drive turbines. CSP differs from solar photovoltaic (PV) technology, which directly converts the sun's ultraviolet radiation to electricity using semiconductors. The CSP technologies discussed here are utility scale although some rooftop CSP applications are being developed. Solar PV rooftop applications are common; however, utility-scale solar PV is also being deployed.

Because no input fuel is required, CSP plants release little or no carbon dioxide equivalent (CO2e) emissions. CSP is a proven technology with more than 350 megawatts (MW) of installed capacity operating commercially in the Mojave desert since the 1980s and several smaller new plants brought on line since 2006. The current worldwide installed capacity is more than 500 MW, relying mostly on the established line-focusing parabolic trough technology that provides peak demand generation. Several emerging technologies that promise higher conversion efficiencies and cost-competitive generation have been demonstrated on a smaller scale. These technologies, such as point-focusing power towers and line-focusing Fresnel reflectors, may extend the ability of CSP to provide shoulder or base load power in addition to peak load.

There is a vast abundance of solar resources and qualified land for deployment of CSP. For example, in the southwestern U.S. alone, eligible land in proximity to transmission would readily allow for 200 gigawatts (GW) of potential CSP production. This would represent approximately 1/5 of projected U.S. installed generating capacity in 2020. The ability to store thermal energy gives CSP technology an advantage over renewable sources such as PV and wind that have not yet developed on-site storage. Although thermal storage has yet to be proven financially viable at commercial scale, plants with thermal heat storage facilities would be able to overcome solar power's intermittent nature, dispatch power on demand, shift generation to periods of peak demand, and achieve a higher capacity factor and thus reduce payback periods.

By the year 2020, an increase of approximately 492 GW of concentrating solar power capacity over today's installed base of 502 MW would reduce emissions by 1 gigaton of CO2e per year. We estimate the total capital cost for such aggressive deployment to be approximately $2.2 trillion, nominal, or $4,546 per kilowatt (kW) of capacity. By 2020, we expect CSP plants to be cost competitive with today's natural gas plants at a levelized cost of electricity (LCOE) of approximately $67 per MWh (in 2009 dollars), a 51% reduction over 2009 LCOE.

The scale-up would produce an estimated 460,000 permanent jobs and 8.7 million temporary jobs in construction. CSP is one of the many gigaton technologies that would increase U.S. energy security and independence by reducing dependence on foreign oil.

An aggressive CSP deployment schedule will encounter obstacles. Foremost, investment in and support for research efforts are required to bring emerging technologies, particularly storage media, to a commercializable, cost-competitive stage. Further, we expect a gigaton ramp-up would result in supply chain bottlenecks, mainly in turbine and storage media supply. While there is a large amount of land worldwide that is suitable for CSP projects, siting and permitting could slow down deployment.

A supportive, stable policy environment will catalyze aggressive deployment of solar thermal generation. Technology-neutral policies, such as a price on carbon, as well as CSP-specific initiatives are required. A loan guarantee program would help overcome the high costs of financing emerging technologies. A streamlined approval process for plant siting and land-use permitting would expedite deployment. Lastly, significant investments in transmission infrastructure on the order of 10% to 20% of total plant capital cost are required; these can be triggered by revisions to rate-of-return regulation to attract private capital as well as federal oversight and a reorganized approval process.