A 110-megawatt solar thermal plant located near Tonopah, Nevada.
Technical Summary

Concentrated Solar Power

Project Drawdown defines concentrated solar power as an electricity generation technology that uses heat provided by direct normal solar irradiance concentrated on a small area, with and without storage. This solution replaces conventional electricity-generating technologies such as coal, oil, and natural gas power plants.

Presently, there are four main concentrated solar power (CSP) technologies competing for the electricity market: 1) parabolic trough collectors (PTC); 2) parabolic dish collectors (PDC); 3) heliostat field collectors (tower); and 4) linear Fresnel reflectors (LFR). Though PTC is the oldest and has the most widespread use, the newest (tower) is the most likely to gain traction, since it is the most economically viable technology that also incorporates storage—an increasing requirement of CSP. This analysis models all CSP technologies, with and without storage.

Methodology

Total Addressable Market

Two total addressable markets were developed for this sector solutions, supported on lower and higher climate emissions mitigation targets linked to different levels of electricity demand and renewable energy sources integration. The total addressable market for concentrated solar power is based on projected global electricity generation in terawatt-hours from 2020 to 2050, with current adoption[1] estimated at only 0.06 percent of generation (13.7 percent).

CSP is particularly promising in regions with more than 2500 kilowatt-hours per meter squared per year of sunlight radiation, such as in the southwestern United States, Central and South America, Northern and Southern Africa, the Mediterranean countries of Europe, the Near and Middle East, Iran, and the desert plains of India, Pakistan, the former Soviet Union, China, and Australia (ESTELA, 2016). This regional potential is accounted within the external sources projections.

Adoption Scenarios

Impacts of increased adoption of concentrated solar from 2020 to 2050 were generated based on two growth scenarios. These were assessed in comparison with a Reference Scenario, in which the solution’s market share was fixed at the current levels.

  • Scenario 1: This scenario is based on the evaluation of yearly averages of four optimistic scenarios: IEA (2017) Energy Technology Perspectives 2DS and B2DS scenarios; IEA (2018) World Energy Outlook SDS; Advanced Scenario from the Greenpeace Solar Thermal Electricity Global Outlook 2016 (Greenpeace et al., 2016). It follows a medium growth trajectory.
  • Scenario 2: The scenario projects a 100 percent adoption of non-fossil-fuel-based technologies in 2050. For this solution the adoption scenario follows a high growth trajectory derived from the above-mentioned model’s scenario results used in Scenario 1.

Financial Model

Based on a meta-analysis of the data collected of these systems around the world, the financial inputs used in the RRS model assume an average installation cost of US$6339 per kilowatt[2] with a learning rate of 20.3 percent, reducing the cost to US$1623 per kilowatt in 2030 and to US$962 in 2050. An average capacity factor of 31 percent is used for concentrated solar power, compared with 57 percent for conventional technologies such as coal, natural gas, and oil power plants. Variable operation and maintenance costs of US$0.046 per kilowatt-hour and fixed costs of US$63.7 per kilowatt are considered for CSP, compared with US$0.005 and US$43.7, respectively, for the conventional technologies.

Integration

Through the process of integrating CSP with other solutions, the total addressable markets were adjusted to account for reduced demand resulting from the growth of more energy-efficient technologies,[3] as well as increased electrification from other solutions such as electric cars  and high-speed rail. Grid emissions factors were calculated based on the annual mix of different electricity generating technologies over time. Emissions factors for each technology were determined through a meta-analysis of multiple sources, accounting for direct and indirect emissions.

Results

Comparing the results from the two modeled scenarios to the Reference Scenario allows us to estimate the climate and financial impacts of increased adoption of CSP. The results for Scenario 1 show that the net cost compared to the Reference Scenario would be US$474.3 billion from 2020 to 2050, with –US$886.4 billion in savings. Increasing the use of CSP from about 0.06 percent in 2018 to 7.3 percent of world electricity generation by 2050 would require an estimated US$1.7 trillion in cumulative first costs. With its low greenhouse gas emissions, under Scenario 1, CSP could reduce 18.6 gigatons of carbon dioxide-equivalent greenhouse gas emissions from 2020 to 2050. Scenario 2 is more ambitious in the growth of CSP technologies, with impacts on greenhouse gas emission reductions over 2020–2050 of 24.0 gigatons carbon dioxide-equivalent.

Discussion

Despite still being in its infancy, CSP has significant potential for helping reverse global warming in an increasingly affordable way. However, the competition and growth of other more mature and less expensive renewable energy sources, such as onshore wind and solar photovoltaic, might delay the short-term adoption of CSP. The main advantages of CSP with storage is the possibility of providing firm and dispatchable power. Nevertheless, when compared with other solar technologies, CSP is heavily dependent on location due to the size of the projects and the irradiance radiation needed.

New CSP capacity is projected to continue growing, but the pace is dependent on policy support schemes, either through stringent greenhouse gas mitigation policies or through financial and regulatory mechanisms for its adoption. Cost reductions will be driven by increasing economies of scale, more competitive supply chains, and technology improvements that will raise capacity factors and/or reduce installation costs.


[1] Current adoption is defined as the amount of functional demand (TWh) supplied by the solution in 2018.

[2] All monetary values are presented in 2014 US$.

[3] For example, LED lighting and high efficiency heat pumps.