Concentrating Solar Thermal Power (CSP)

CSP Markets

The global installed capacity of concentrating solar thermal power (CSP) increased by 200 MW in 2022 to reach a total of 6.3 GW. ¹ (See Figure 28.) This growth followed the first year ever of contraction of global CSP capacity in 2021. ² Overall, the global CSP market has slowed following an initial surge of development in Spain and the United States in the early 2010s. ³ Neither of these historically leading markets has added capacity in nearly a decade. However, new projects have come online and are under construction in emerging markets, including Chile, China, Israel, Morocco, South Africa and the United Arab Emirates. ⁴

In 2022, the first portion (200 MW) of a 600 MW parabolic trough facility came online at a large-scale hybrid CSP power plant in the United Arab Emirates. ⁵ Once completed, the plant will be the world's largest CSP facility at 700 MW (including the 100 MW central tower). ⁶ It is spread over 77 square kilometres and combines solar PV and CSP; the 266 metre solar tower, the world's largest, entered commercial operations in early 2023. ⁷

Most of the world's CSP capacity under construction is in China. As of the end of 2022, at least 30 CSP projects were in various stages of construction and commissioning in the country, with 14 projects (totalling 1.4 GW of capacity) scheduled to come online during 2023. ⁸ If these projects are completed as scheduled (which is highly uncertain), it would raise the global cumulative CSP capacity by roughly 23%, equivalent to the total operational capacity in the United States as of 2022. ⁹ In early 2023, the first of these Chinese projects started commercial operations, a 50 MW tower CSP facility. ¹⁰

The main drivers for CSP in China are the “dual carbon” plan, which aims to give flexibility to the grid; policy support to drive cost reductions; R&D at 11 major universities; and a local CSP supply chain comprising more than 500 Chinese firms. ¹¹ A state council action plan also proposes developing CSP, promoting its co-location with wind power and solar PV. ¹² In addition, the 14th Five-Year Plan for a Modern Energy System (2021-2025) promotes the active development of CSP as well as the coordinated deployment and joint operation of CSP, wind and PV power generation facilities in regions such as Gansu, Inner Mongolia, Qinghai and Xinjiang. ¹³ Western regions in China with a high level of solar irradiation are encouraged to use CSP as a power source for peak shaving. ¹⁴

China is notable for its focus on solar tower systems. Whereas most of the world's historic CSP capacity (more than three-quarters) is parabolic trough (and only 20% tower), in China more than 63% of projects are solar tower, while only a quarter are parabolic trough. ¹⁵

As of end-2022, around 1.3 GW of CSP capacity was still in operation in the United States, with no projects under planning or construction. ¹⁶ The country has not added new CSP capacity since 2015. ¹⁷ However, the Inflation Reduction Act of 2022 was expected to give CSP a boost, earmarking USD 24 million to fund CSP technologies for electricity generation as well as for industrial process heat. ¹⁸

FIGURE 28.

Concentrating Solar Thermal Power Global Capacity, by Country and Region, 2012-2022

Spain has added no new CSP capacity since 2013 and faced further setbacks during 2022. Although the country had aimed to award 220 MW of new CSP capacity at a renewable energy auction in October, no capacity was awarded. ¹⁹ This was due mainly to industry requesting a higher price than the government was willing to offer, and to industry uncertainty about the possibilities to access the electricity grid. ²⁰ Spain aims to double its CSP capacity from 2.3 GW to 4.8 GW by 2025 and 7.3 GW by 2030, yet the country had no capacity under construction in 2022. ²¹

Italy had 8 MW of CSP capacity under construction in 2022 and aims to add 880 MW by 2030. ²² In South Africa, the Redstone CSP plant began construction and is expected to be completed in 2023, with 100 MW capacity and 12 hours of storage. ²³ In Africa, Botswana moved forward in a tendering process for a 200 MW CSP plant, and a feasibility study was conducted for a CSP facility in Namibia. ²⁴ An Australian company received AUD 65 million (USD 44 million) to construct a novel plant design consisting of several small towers, as opposed to the single large tower that is typical of solar tower plants. ²⁵

CSP Industry

The main companies active in the CSP industry in 2022 were based in China, Spain and the United Arab Emirates. ²⁶ They included project developers Shanghai Electric, Abengoa, Acciona Energia, and ACWA Power, as well as several smaller firms.

The cost ⁱ of electricity generated by CSP plants fell 68% between 2010 and 2021. ²⁷ This decline was driven largely by decreases in total installed costs and by improved capacity factors. ²⁸ The growing addition of thermal energy storage also has grown plant capacity factors, improving plant dispatchability while decreasing levelised electricity costs. ²⁹ In addition, hybridisation with solar PV has been responsible for driving down CSP costs, especially in China. ³⁰

Upfront costs rebounded in 2021, although the increase should be considered with caution, as only one project was brought online. ³¹ (Cost data for 2022 were not available at the time of publication.) Technology could play a growing role in driving down costs, as cleaning of heliostats (a major component in tower CSP plants) and cloud cover prediction have the highest potential for increasing the value of CSP plants. ³² Hybrid projects could drive costs down further. A 2021 study found that Chilean hybrid solar PV-CSP plants could reach lower levelised electricity costs than gas-fired power plants, while providing the same flexibility benefits to the system. ³³

Research and development of CSP systems continued in 2022. The United States and China lead the world in patent applications for the technology, each accounting for around 20% of all applications. ³⁴ In early 2023, construction began on the final stage of a USD 100 million CSP demonstration project in the United States. ³⁵ The US Department of Energy has a goal to reduce the cost of heliostats one-third by 2030 from its 2021 level. ³⁶ In 2022, China provided total funding of RMB 8.06 million (USD 1.2 million) for a total of 21 CSP research projects (12 youth projects, 8 general programmes, and 1 regional and international cooperation and exchange project). ³⁷