Concentrating solar power (CSP)

Concentrating Solar Power (CSP) technologies are renewable energy systems designed to

generate clean electricity by focusing sunlight to produce high temperatures, which then drive

conventional power generators. The increasing global warming and depleting fossil fuel

reserves make the switch to renewable technologies like CSP an urgent need. CSP technologies

are considered technically and commercially proven and can be hybridised with fossil fuels or

integrated with storage systems for continuous operation.

• Linear Fresnel Collector (LFC): Another one-axis tracking technology, LFC uses flat,

ground-mounted mirrors to reflect sunlight onto elevated, inverted linear fixed receivers,

also a line focus technology producing heat at about 400-550 °C.

• Tower Power (TSP) / Central Receiver Technology: This two-axis tracking technology

uses numerous heliostats (sun-tracking mirrors) to reflect sunlight onto a central receiver

at the top of a tower, achieving high temperatures (600-1000 °C). TSP is a point focus

technology.

• Stirling/Dish Technology (SDC): This also uses two-axis tracking, with a parabolic dish

concentrating sunlight onto a receiver at its focal point, generating very high temperatures

(above 1000 °C) to power a Stirling engine or micro-turbine directly attached to the

receiver. SDC is a point focus technology.

• Line focus technologies (PTC and LFC) concentrate sunlight about 100 times, while point fo-

cus technologies (TSP and SDC) concentrate it about 1000 times, leading to higher operating

1temperatures and potentially greater efficiency for point focus systems. However, line focus

technologies are generally less expensive and technically less complex.

1.2 Historical Development of CSP Technologies [36]

1. Parabolic Trough Collector (PTC):

• In 1913, the first parabolic trough system was built in Maadi, Egypt, to generate steam for

a 73 kW pump used for irrigation. Captain John Ericsson had earlier invented a solar pow-

ered hot air engine using a parabolic concentrator in 1864.

• After 1913, Sandia National Laboratories in the U.S. sponsored PTC development. Large-

scale development for industrial process heat (IPH) applications began in the mid-1970s.

• In the 1980s, the International Energy Agency (IEA) constructed the SSPS/DCS project in

Spain, using different types of parabolic trough collectors.

• Luz International Limited developed a parabolic trough module for IPH based on the

DOE/Sandia and SSPS projects.

• The first commercial CSP plant worldwide, SEGS I (14 MWe), using PTC technology, was

built by Luz in California and began operation in 1984. The capacity of the SEGS plants

increased to 354 MWe by 1990. SEGS I and II are considered the first stage in proving the

commercial viability of trough technology.

2. Linear Fresnel Collector (LFC):

• The principle of LFC was developed by Baum et al. in 1957.

• Giorgio Francia designed both linear and two-axis tracking Fresnel reflectors and built the

first LFC prototype at Lacédémone–Marseilles solar station, which was tested in 1964 and

generated steam.

• Belgian company Solarmundo built a 2500 m² prototype in 2001. Solarmundo later merged

with Solar Power Group, Germany, who built a pilot LFC system named Fresdemo in

Spain.

3. Tower Solar Power (TSP):

• The earliest solar tower power plant demonstrated was EURELIOS in Adrano, Sicily, Italy,

in 1965, generating 1 MWe. Construction by a European consortium was completed in

1980.

• The ability to generate large-scale electricity (10 MWe) was demonstrated by the Solar One

plant built in California, U.S., in 1982.

• The Solar Two plant, an upgrade of Solar One, demonstrated the use of molten salt as a

heat transfer and storage medium, operating from June 1996 to 1999.

• The first water/steam receiver tower plant under a pure commercial approach, Planta Solar

10 (PS10), was built by Abengoa Solar in Sevilla, Spain, and began operation in 2007.

4. Stirling/Dish Technology (SDC):

2• Developed and demonstrated in the late 1970s and early 1980s by companies like United

Stirling AB and Advanco Corporation.

• Advanco’s Vanguard system in Southern California (1982-1985) achieved a net conversion

efficiency of 29.4% but experienced technical problems.

• In 1984, Schlaich-Bergermann und Partner operated two 50 kWe Stirling dish engines in

Saudi Arabia.

• Stirling Energy Systems (SES) developed the SunCatcher™ system, and a prototype

achieved a net solar-to-grid conversion efficiency of 31.25% in 2008.

• The first demonstrated plant composed of 60 SunCatcher™ units (1.5 MWe) was built in

Arizona in 2009, but it was later decommissioned.

PTC is currently the most technically and commercially successful CSP technology, with a

long history of operation in commercial projects. While other technologies like LFC and TSP

are also advancing and being deployed, SDC, despite its high efficiency, remains commercially

unavailable due to cost. There is a current trend towards employing non-PTC technologies in

future projects due to improvements in their performance.

The recent 6th IPCC Assessment Report strongly indicates that if significant and rapid reduc-

tions in greenhouse gas emissions across all sectors don’t occur, the aim of capping global

warming at 1.5 ◦C is now beyond reach [1]. To achieve this temperature goal, a global transition

to more sustainable production and consumption systems is already underway, particularly

within the energy sector, where solar photovoltaic (PV) and wind energy represented 12% of

global electricity generation in 2022, a substantial rise from just 0.6% in 2007 [2]. Notably,

over 80% of all new power-generating capacity installed in 2020 was derived from renewable

energy sources [3]. The sharp increase in natural gas and coal prices during the years 2021-

2022 has further diminished the appeal of fossil fuels, making solar and wind energy more

attractive [4]. However, the variability of renewable energy sources such as solar and wind

presents challenges for maintaining grid stability, as unexpected weather changes can signifi-

cantly affect their energy production. As a result, the increasing share of intermittent renewable

energy from sources like wind and solar PV raises concerns about the electricity grid’s stability,

given their unpredictable generation that fluctuates with weather changes. Although non-dis-

patchable renewable systems aim to replace fossil fuel consumption, a higher share of variable

3generation introduces challenges, including the need for additional backup capacity, increased

curtailments, and greater overall system costs [5]. For instance, a heightened dependency on

non-dispatchable renewables necessitates the construction of more conventional backup power

plants, such as gas and coal, which leads to greater curtailments and consequently elevated

electricity prices due to the increased expenses of the entire energy system [6-8]. Nonetheless,

this problem can be mitigated by enhancing the ratio of dispatchable renewables in the energy

mix. The shift toward a low-carbon economy is expected to significantly increase the demand

for energy storage solutions to manage the unpredictability of renewable sources like solar PV

and wind. Concentrated solar power (CSP), combined with thermal energy storage (TES), can

efficiently meet both the intermittency and storage demands by providing dispatchable renew-

able electricity. CSP is considered one of the most promising technologies for improving

renewable energy systems to enable rapid decarbonization of the electricity sector toward sce-

narios featuring extensive renewable energy deployment [9-15]. A distinctive aspect of CSP

that sets it apart from other renewable technologies is its inherent compatibility with large-

scale thermal energy storage and hybrid fossil fuel systems. This interconnection enhances the

technology’s resilience to natural variations in solar irradiance, thereby ensuring consistent

power outputs, which are crucial for the smooth incorporation of solar electricity into the grid

[16]. Incorporating thermal energy storage into CSP facilities boosts their dispatchability with-

out substantially increasing the levelized cost of electricity in comparison to CSP facilities

without storage capabilities [17-18]. This enhancement strengthens CSP’s potential as a vital

method for generating dispatchable renewable electricity. The ability to provide on-demand

power makes CSP particularly suitable for large-scale electricity generation, which is espe-

cially beneficial for balancing the variability of other renewable sources such as wind and solar

PV. Numerous strategic forecasts highlight CSP’s essential role in crafting net-zero energy sys-

tems. In support of this, the ‘Net Zero by 2050’ report from the IEA, featuring strategies for

climate change mitigation, emphasizes the urgency of achieving CO2 elimination to confine

global warming below 2◦C by the end of the century. Hence, alongside the transition to renew-

able energy sources, it is vital to consider the heat requirements for removing CO2 from the

atmosphere. CSP’s unique solar thermal characteristics enable it to effectively realize high

capture and regeneration thermochemistry, allowing it to play a significant role in reducing

atmospheric CO2. The International Energy Agency (IEA) predicts substantial growth in CSP,

estimating capacities of 73 GW, 281 GW, and 426 GW by the years 2030, 2040, and 2050,

4respectively [19]. Moreover, the International Renewable Energy Agency (IRENA) expects

CSP capacity to increase to a range of 52–83 GW by 2030 [20].

The economic viability of concentrating solar power (CSP) plants is a crucial factor for their

acceptance and large-scale deployment. Key economic elements influencing the competitive-

ness of CSP include initial capital costs, capacity factors, maintenance and operational ex-

penses (O&M), and the levelized cost of electricity (LCoE) which are visualised in figure 1 [21].

2.1 The Capital Costs

CSP plant capital costs include the initial investment required for site development, technology

components like power blocks, mirrors and receivers, and the balance of plant, as well as en-

gineering, procurement, and construction activities. Capacity-based capital costs are the total

installation costs for each unit of power capacity, expressed in dollars per kilowatt ($/kW).

Component prices, plant size, location, and storage time are some of the variables that impact

CSP capital costs. As opposed to solar PV, CSP is heavily impacted by economies of scale and

works best for large-scale generation (usually ≥50 MW) to reduce energy production costs.

However, this requires relatively high capital investments and financial risks, in part because

the technology is more complex and not everyone can handle it. The adoption of CSP was

limited in its early stages of commercialization because it was frequently not cost-effective to

incorporate thermal energy storage. However, nearly all proposed and operational CSP plants

have multiple hours of thermal storage since around 2015, enabling dispatchable electricity

generation at night and in the evening. Nowadays, adding thermal storage is thought to be a

financially feasible way to increase capacity factors, improve utilization and project econom-

ics, and provide more scheduling flexibility for generation. The typical thermal storage capac-

ity for commissioned CSP facilities surged dramatically from 3.5 hours in 2010 to 11 hours by

2020 [22,23,24]. Recent projects in China have an average storage capacity of around 9 hours.

Given these developments, it is expected that nearly all forthcoming CSP projects worldwide

will feature considerable thermal energy storage [27].

When evaluating the economic feasibility of CSP facilities, capacity factors are an essential

factor. The capacity factor of a CSP facility reflects the ratio of its average annual output to the

theoretical maximum annual output, provided that it maintains a full-scale rating capacity dur-

ing the year. Greater capacity means better plant use and better financial sustainability. Because

5operating for more hours, fixed capital expenditures are spread over larger amounts of electric-

ity generated, resulting in lower linear electricity costs (LCoEs). Power factors are influenced

by the characteristics of solar resources, including the existence of normal direct radiation

(DNI), daily and seasonal patterns, energy block reliability, and thermal energy storage (TES).

By enabling electricity generation beyond sunset, TES strengthens the capacity factors of the

CSP plant. In general, higher capacity factors have a positive effect on the economics of the

CSP by increasing energy production without additional capital costs. As capacity factors im-

prove due to technological advances, LCoE values are significantly decreasing [21].

The global average capacity factors for Concentrated Solar Power (CSP) increased from 30%

in 2011 to 50% in 2021, representing a 66% rise over the ten-year span. This improvement can

be primarily linked to the enhanced use of thermal energy storage (TES), which allows for

energy production to be adjusted to periods of heightened electricity demand or value. Over

the last decade, the decrease in costs associated with thermal energy storage and advancements

in operating temperatures have significantly contributed to making CSP more economically

viable. Looking ahead, the average capacity factor for new CSP systems is projected to reach

60% by 2030, fueled by continuous enhancements in TES, power block flexibility, and solar

field performance. Ongoing efforts to improve thermal capacity factors through better optical

efficiency, cutting-edge receiver coatings, improved heat transfer fluids, and effective manage-

ment of the solar field will also be vital for achieving these ambitious targets in a cost-effective

way [21].

The expenses associated with operation and maintenance (O&M) are crucial for assessing the

overall financial feasibility of CSP plants. In comparison to other renewable energy technolo-

gies such as solar photovoltaics (PV) and onshore wind, CSP O&M costs are significantly

higher, both in absolute terms and as a percentage of operating costs. The elevated O&M ex-

penses can be attributed to the increased mechanical and operational complexity found in CSP

systems, which consist of extensive arrays of mirrors, heat transfer systems, thermal storage,

and conventional turbine generators. However, with the maturation of the industry, O&M ex-

penses have decreased due to enhanced designs and increased economies of scale. The total

O&M expenditures for a CSP facility include all the ongoing costs necessary to run and

maintain the plant throughout its operational lifespan. These expenditures cover routine

6maintenance for solar field mirrors, receivers, heat transfer fluid systems, thermal energy stor-

age, the power block, and other aspects of the plant. There are additional costs linked to staffing

for plant operations, insurance, spare parts inventory, and the periodic refurbishment or re-

placement of components. Generally, O&M costs comprise both fixed and variable elements

that correlate with the net generating capacity and the annual electricity output of the facility.

Key factors that affect O&M costs for specific CSP projects include the type of solar field

technology (for example, PTC, SPT, or LFR), the quality of solar resources and the annual

Direct Normal Irradiance (DNI) at the site, the hours of thermal energy storage capacity, the

type of power block (whether steam turbine or combined cycle), plant capacity and design

intricacy, local labor costs for operational and maintenance staff, and the development level of

the regional CSP supply chain and O&M expertise [21].

In Europe, the yearly costs for operation and maintenance (O&M) typically range between 25

and 35 dollars per kilowatt. These O&M costs greatly impact the overall levelized cost of

electricity (LCoE) for a concentrated solar power (CSP) project, often accounting for approxi-

mately 18-20% of the total expenses. This proportion is 2-4 times higher than the O&M share

observed in solar photovoltaic (PV) or onshore wind energy initiatives. Recognizing the im-

portance of this cost element is crucial when assessing competitiveness. Reducing O&M

expenses is essential for lowering the LCoE of CSP. A decrease of 20% in O&M costs could

elevate the internal rate of return on CSP projects from 11.4% to 13.4%, contingent on the

specific technology used, such as parabolic trough collectors (PTC), solar power towers (SPT),

or linear Fresnel reflectors (LFR) [21].

The levelized cost of electricity (LCoE) has become an important financial metric for

evaluating and comparing different electricity generation technologies. LCoE represents the

cost per kilowatt-hour linked to the development and functioning of a power facility over its

entire operational life. This metric facilitates an easy comparison of technologies that have

varying cost structures, operational lifetimes, energy outputs, and production patterns. It

reflects the returns needed for an investor to reach the breakeven point. Reduced LCoE values

signify enhanced economic competitiveness. The LCoE of CSP facilities is influenced by

various critical factors [21].

– The initial capital costs encompass site preparation, procurement of components, installa-

tion of the system, connection to the grid, and financing expenses.

-The plant’s efficiency in converting sunlight into electricity and its capacity factor.

– Ongoing expenses for operations and maintenance, in addition to insurance costs throughout

the plant’s service life.

pared to other energy generation technologies. Reducing capital costs, improving plant perfor-

mance, choosing sites with optimal sunlight exposure, and securing favorable financing are

crucial for minimizing the LCoE of CSP initiatives.

Globally, the average levelized cost of electricity (LCoE) for newly constructed concentrating

solar power (CSP) plants experienced a notable reduction of 67% between 2010 and 2020,

falling from $0.31/kWh to $0.098/kWh. This drop can be linked to lower capital expenditures,

improved capacity factors, and decreased operational and maintenance (O&M) costs. Contrib-

uting factors to this trend include continuous declines in capital costs, improved capacity fac-

tors, reductions in operational and maintenance expenses, and lower financing costs. Never-

theless, the progress of CSP in achieving these ambitious LCoE targets will necessitate appro-

priate policies and incentives to support continuous development [21].

The levelized costs of CSP have decreased, likely due to higher irradiance levels at newer plant

sites, reduced total installed expenses, larger thermal storage systems, and enhanced capacity

factors.

The amount of insolation has a significant impact on how solar systems are used on land. The

same system may need up to three times as much land for high latitudes as for sites nearer the

equator because the amount of land used at a given site decreases with increasing insolation.

Around the world, CSP plants need a sizable area of land that is largely level.[29]

Land-use impacts are assessed using at least three broad criteria: (1) the affected area, (2) the

impact’s duration, and (3) the impact’s quality. The “damage function,” also known as the

8quality of the impact, assesses the initial and final states of the affected land in terms of a

number of variables, such as soil and ecosystem quality. Two land-use metrics are taken into

account. The first is the total area, which includes all of the land that the site boundary encloses.

Usually fenced or otherwise protected, the area’s perimeter is described in blueprint drawings.

The land directly occupied by solar arrays, access roads, substations, service buildings, and

other infrastructure is known as the “direct impact area,” and it is the second metric. The direct-

impact area is contained within the total-area boundaries and is smaller than the total area. Land

use is quantified on a basis of capacity (area/MWel) and generation (area/GWh/yr). Because

power plants are frequently rated according to their capacity, capacity-based results are helpful

for estimating land area and costs for new projects. Evaluation of land-use impacts that vary

by solar resource differences, tracking configurations, and technology and storage options is

made possible by the generation basis, which also offers a more consistent comparison between

technologies with different capacity factors.[30]

Land usage is generally lower than for coal, biomass, and hydropower, but higher than for

nuclear, wind, and geothermal power plants. Growing global energy demand will eventually

force the use of secondary and tertiary recovery technologies in oil and gas extraction as well

as lower-quality, open-pit coal mining (e.g. shale gas and tight oil). Accordingly,

nonrenewable energy sources will eventually have a larger land footprint, whereas renewable

energy sources should eventually have a smaller one [29].

This indicates that solar thermal power plants with a dry cooling system can cut the life-cycle

water consumption of a parabolic through the plant with TES by 80%. But there are also

important trade-offs when it comes to water conservation. Compared to wet cooling plants,

9capital costs are about 10% higher and power consumption can be up to 1% higher. According

to certain studies, switching from wet to dry cooling in a 100 MW parabolic trough a CSP plant

can reduce water consumption from 3 to 60 m3/MWh to 0 to 25 m3/MWh. However, using dry

cooling rather than wet cooling raises investment costs and reduces plant efficiency, increasing

the leveled electricity cost by 3 to 7 percent. Additionally, this results in an 8% increase in

Cumulative Energy Demand (CED) and LC GHG emissions. Furthermore, dry-cooling

technology performs worse in environments with temperatures higher than 38 °C. Lastly, there

are CSP designs with minimal freshwater needs, like gas turbine towers and parabolic dishes

with Stirling engines [29].

This information indicates that wet cooling uses more water than dry cooling. Even though dry

cooling has drawbacks of its own, many facilities will be switching to dry cooling today, which

will significantly reduce water consumption.

The CSP plant will undergo maintenance throughout its lifecycle, and waste related to

electricity production will be disposed of. Oily rags, empty containers, rusted and broken metal

and machine parts, electrical waste, and other solid wastes, including the usual waste generated

by employees, are all examples of power plant waste [29].

A power plant’s operations may generate various types of hazardous waste. Cleaning rags, used

or expired chemicals from the water treatment system, paints, solvents, waste HTF, and oil and

oil filters are some examples of this waste [29].

3.4 Gases Emitted Into the Atmosphere

Depending on the technology, CSP plants have different environmental effects. GHG

emissions and other pollutants are generally decreased without posing new environmental

hazards. The annual production of 0.25 to 0.4 t of CO2 can be avoided with just one square

meter of CSP concentrator surface. Considering that CSP systems have a lifespan of roughly

25 to 30 years, their energy payback period can be as short as five months. The majority of

CSP solar field materials are recyclable and can be used again in new plants. For trough, tower,

Stirling, and Fresnel systems, most estimates range from 14 to 32 g CO2 eq/kWh, and the

10literature that is currently available shows little variation in technology. Although there isn’t as

much research on CSP systems as there is on some PV designs, lifecycle GHG emissions for

these technologies seem to be fairly consistent at this point, though it is advised to supplement

with more lifecycle assessments [33].

Phase extraction and component manufacturing account for 12–97% of total CO2 production,

construction accounts for 0.02%, plant phase production accounts for 86–5%, and dismantling

and disposal accounts for 0.51%. The majority of greenhouse gas emissions linked to the

manufacturing of solar field components come from the production of mirrors and galvanized

steel.

3.5 Materials in CSP Plants

Compared to traditional fossil fuel power plants, CSP plants use a lot more working materials

within their system. The most frequently used materials are concrete, steel, and glass, all of

which have a comparatively high recycling rate—usually greater than 95 percent. The majority

of materials that cannot be recycled are inert and can be safely land-filled or used to build

roads. Nonetheless, the CSP system contains a number of hazardous substances, most

frequently synthetic organic compounds like biphenyls and biphenyl ether, which are employed

in the heat transfer system. These substances must be handled as hazardous waste because they

have the potential to start a fire and may leak into the ground, where they may find their way

to other areas of the environment. Plants can absorb toxic substances from the soil, and animals

can also absorb these substances by consuming the plants. Replacing toxic materials with water

or molten salts is one method they use to try to solve the problem [29].

By substituting water and molten salt for the environmentally hazardous materials originally

used in CSP, environmental harm was avoided.

decreasing the likelihood that these species will survive. Similarly, the number of invasive

species in that region might rise. when moving tools and supplies for species that are not native

to this ecosystem or that are alien species. Foreign species that are invasive frequently have the

capacity to spread quickly, endangering native species in the process. Wind flow profile is

impacted by collector arrays in CSP plants. Within the collector field, the kinetic energy of

turbulence increases while the mean wind speed is sharply decreased. Since speed is crucial

for the spread of the desert, lowering wind speed has many advantages. In other words, the

collector field helps to prevent soil erosion. The soil temperature beneath the collector is also

impacted by the collector field in CSP plants. The soil temperature outside the collector field

may be several degrees Celsius higher in the winter and several degrees Celsius lower in the

spring and summer, depending on where the plant is located. [29]

Social Hotspot Index (SHI). This index provides a quantitative measure for comparing the

level of social risk across different economic sectors and potentially across different

countries. A higher SHI value signifies a greater prevalence of social risks within a

particular sector. The SHI considers five impact categories.

labour laws, and the treatment of migrant workers. [37]

Furthermore, the analysis often indicates that unemployment risk can be a significant concern

in other sectors that are projected to experience increased employment as a result of CSP

projects. While these projects generate new job opportunities, the sectors involved might

already be characterised by underlying vulnerabilities related to unemployment, potentially

receiving a “high” risk value.

Despite the identification of these social risks, the development of CSP projects can also be

viewed as a mechanism for potentially reducing unemployment risks within the stimulated

sectors by creating new employment opportunities. The social risk assessment conducted

suggests that the project would support the reduction of unemployment risks within the most

affected sectors. Therefore, while social impact assessments highlight existing vulnerabilities,

they also imply that these projects can contribute positively to employment figures.

In conclusion, the assessment of social impacts associated with CSP projects underscores that

while these developments can lead to job creation and economic growth, it is crucial to consider

the underlying social risks within the expanding sectors, particularly those related to labour

and human rights, with unemployment frequently emerging as a key concern. The application

13of comprehensive tools like the SHDB facilitates a more holistic understanding of the potential

social consequences, encompassing a range of factors beyond mere job creation figures.

To further lower the expenses associated with CSP and enable its large-scale deployment in

the future, especially when renewable energy dispatchability is required, policy must actively

encourage both the development and innovation of this technology today. Unlike previous sup-

port initiatives, which were primarily found in developed nations, policies promoting CSP are

necessary in desert regions such as the US and Australia, but especially in developing countries

with expanding electricity markets, including China, India, and nations in Latin America, the

MENA region, and southern Africa. In this regard, the trend is promising: CSP support initia-

tives and research, development, and demonstration (RD&D) policies have extended beyond

Europe and the US, and now transitional nations are leading the expansion. For CSP to continue

advancing and growing, this spread of CSP support to additional countries must persist [28]

5.2 Policies for deployment

Since dispatchability is essential for Concentrated Solar Power (CSP), and industry continuity

and diversification are crucial for cost reductions, three key points are critical for supporting

deployment: it should incentivize dispatchability, incorporate firm and predictable cost pres-

sures, and enable a gradual and reliable pace of expansion. Regarding the dispatchability in-

centive, the level of dispatchability varies based on the system where CSP is required: alterna-

tives include time-of-day pricing (as seen in South Africa) in cases of distinct peak demand; in

situations with a flatter demand curve, a baseload or availability criterion, like that in Chile

(ensuring constant capacity availability from 7:00 a.m. to midnight), may be more fitting. Con-

cerning the types of instruments, we identify at least two viable options that can meet all three

criteria [28]. The initial option involves auction schemes, which currently serve as the primary

tool for promoting CSP deployment. Such policies are therefore viable, and elements that

consider all three aspects mentioned earlier have been incorporated into at least one auction

scheme previously, though no nation has included all three components to date. [28].

An alternative option that could more effectively meet all three criteria is the implementation

of feed-in tariffs. These tariffs provide for automatic grid connection and tariff access for all

14facilities that meet specific established standards, thereby ensuring a consistent and reliable

flow of projects. Implementing degressive, time-of-day incentivized feed-in tariffs without a

capacity limitation (or with a cap sufficiently high to accommodate multiple projects each year)

could serve as an effective tool for advancing CSP deployment, ensuring not only increased

expertise in construction and operation but also the retention of this expertise within financially

viable companies. Such a framework would likewise be practical to execute, and various

elements have been incorporated into feed-in tariffs globally [28].

Simply deploying technology may not be enough to stimulate innovation in Concentrated Solar

Power (CSP) since there is a high technology risk associated with new methods, and private

funding for research, development, and demonstration (RD&D) in the electricity sector is in-

famously low. Additionally, developers often have legitimate reasons to adopt a conservative

approach to plant design. There are two specific types of policy instruments that could effec-

tively address this issue. Firstly, RD&D facilities can play a crucial role in testing and devel-

oping innovative CSP system designs by facilitating the examination of new configurations,

components, materials, or systems on a larger scale, beyond laboratory settings. These plants

can also serve as demonstration sites to validate new concepts, such as utilizing an organic

Rankine cycle in low irradiation areas or utilizing CSP waste heat for alternative applications

like cooling or water desalination, and can foster further development through experiential

learning. Most of the limited existing RD&D CSP plants are situated in Europe or the United

States, with none located in areas where CSP potential is greatest, even though operating con-

ditions may vary significantly. For instance, RD&D plants in the sandy deserts of the Gulf

region or in high-altitude locations in Chile or China could be crucial for developing and testing

new components and designs suited to these specific conditions. Strengthening existing inter-

national research collaborations and establishing new ones will also promote the dissemination

of innovative CSP solutions [28]. Secondly, deployment support can also be directed toward

fostering innovation, both by crafting the support criteria and by introducing additional dedi-

cated instruments.

5.4 Findings and policy considerations

It is proposed that a variety of policy tools should be implemented simultaneously in arid

regions where CSP could make a significant impact in the near future [28].

15These instruments serve as deployment strategies intended to leverage the primary benefit of

CSP – its ability to be dispatched – while also managing overall cost pressures to encourage

cost reductions and the development of more efficient plant designs, ensuring that industry

profits are sufficient to sustain business operations. Such strategies, which may take the form

of auctions or feed-in tariffs, need to incentivize dispatchability, provide consistent and defined

cost pressures, and support a gradual and reliable growth rate. Options like time-of-day bo-

nuses, a long-term strategy for reducing support, and either a significant or no capacity cap in

the support frameworks are established and viable methods to meet these criteria within na-

tional auction or feed-in tariff systems [28].

Conversely, simply deploying technologies may not be enough to foster innovation and lower

costs in the long run; to achieve this, specific research, development, and demonstration

(RD&D) policies may be required in the regions where deployment is encouraged. These pol-

icies could encompass demonstration facilities tailored to the particular environments where

growth is anticipated in the near to medium future. Additionally, they should offer provisions,

included in deployment assistance, that help mitigate or distribute the heightened risks associ-

ated with implementing new and innovative components and designs, thereby encouraging

cautious developers to pursue and experiment with groundbreaking technical advancements

[28].

Enacting these two policy frameworks simultaneously could offer the CSP sector a harmonious

blend of appealing profits and competitive dynamics, establishing a foundation to grow CSP

while also decreasing expenses, preparing it for widespread implementation when necessary

[28].