This roadmap envisages development and deployment of CSP along the following paths:
By 2050, with appropriate support, CSP could provide 11 .3% of global electricity, with 9.6% from solar power and 1.7% from backup fuels (fossil fuels or biomass).
In the sunniest countries, CSP can be expected to become a competitive source of bulk power in peak and intermediate loads by 2020, and of base-load power by 2025 to 2030.
The possibility of integrated thermal storage is an important feature of CSP plants, and virtually all of them have fuel-power backup capacity.
Thus, CSP offers firm, flexible electrical production capacity to utilities and grid operators while also enabling effective management of a greater share of variable energy from other renewable sources (e.g. photovoltaic and wind power).
This roadmap envisions North America as the largest producing and consuming region for CSP electricity, followed by Africa, India and the Middle East.
Northern Africa has the potential to be a large exporter (mainly to Europe) as its high solar resource largely compensates for the additional cost of long transmission lines.
CSP can also produce significant amounts of high-temperature heat for industrial processes, and in particular can help meet growing demand for water desalination in arid countries.
Given the arid/semi-arid nature of environments that are well-suited for CSP, a key challenge is accessing the cooling water needed for CSP plants. Dry or hybrid dry/wet cooling can be used in areas with limited water resources.
The main limitation to expansion of CSP plants is not the availability of areas suitable for power production, but the distance between these areas and many large consumption centres.
This roadmap examines technologies that address this challenge through efficient, long distance electricity transportation.
CSP facilities could begin providing competitive solar-only or solar-enhanced gaseous or liquid fuels by 2030. By 2050, CSP could produce enough solar hydrogen to displace 3% of global natural gas consumption, and nearly 3% of the global consumption of liquid fuels.
Key actions by government in the next ten years
Concerted action by all stakeholders is critical to realising the vision laid out in this roadmap. In order to stimulate investment on the scale required to support research, development, demonstration and deployment (RDD&D), governments must take the lead role in creating a favourable climate for industry and utilities.
Specifically, governments should undertake the following:
Ensure long-term funding for additional RD&D in: all main CSP technologies; all component parts (mirrors/heliostats, receivers, heat transfer and/or working fluids, storage, power blocks, cooling, control and integration); all applications (power, heat and fuels); and at all scales (bulk power and decentralised applications).
Facilitate the development of ground and satellite measurement/modelling of global solar resources. Support CSP development through long-term oriented, predictable solar-specific incentives. These could include any combination of feed-in tariffs or premiums, binding renewable energy portfolio standards with solar targets, capacity payments and fiscal incentives. Where appropriate, require state-controlled utilities to bid for CSP capacities.
Avoid establishing arbitrary limitations on plant size and hybridisation ratios (but develop procedures to reward only the electricity deriving from the solar energy captured by the plant, not the portion produced by burning backup fuels).
Streamline procedures for obtaining permits for CSP plants and access lines. Other action items for governments, and actions recommended to other stakeholders, are outlined in the Conclusion.
California Approves 1,000-Megawatt CSP Plant
The California Energy Commission (CEC) approved the construction and operation of four concentrating solar power (CSP) plants, which, if constructed, will combine to make the world’s largest CSP facility, generating about 1,000 megawatts (MW) of electricity. The project will be located about 215 miles northwest of San Diego near Blythe, California, near the Arizona border on land owned by the U.S. Bureau of Land Management (BLM).
Jointly developed by Solar Millennium LLC, of Oakland, and Chevron Energy Solutions, the project will use solar parabolic trough technology to generate electricity. Arrays of parabolic mirrors spread across roughly 7,000 acres will collect heat from the sun and focus it on receiver tubes, where a heat transfer fluid will be heated to 750°F. The hot fluid will be piped through a series of heat exchangers which will release the heat to generate high pressure steam. That steam will then be fed to steam turbine generators at each of the four plants to produce electricity.
The project is expected to prevent roughly 2 million tons of carbon dioxide emissions each year, compared to fossil-fueled energy production. The 20-year power purchase agreements between Solar Millennium and Southern California Edison for the first two solar power plants were approved by the California Public Utilities Commission in July.
The BLM must still approve the project, but Solar Millennium expects that approval to come in October. The company plans to begin construction on two of the four plants later this year.
California Governor Arnold Schwarzenegger said, "I applaud the California Energy Commission’s decision to approve the construction of the Blythe Solar Power Project—the world’s largest—and am excited to see other solar projects move forward. Projects like this need our immediate attention, as solar and renewable power are the future of the California economy."
The Blythe project is the fourth concentrating solar power project approved by the CEC since mid-July. For more information, see the CEC Web pages on the Solar Millennium Blythe Project, the 250-MW Abengoa Mojave Solar Project, the 250-MW Beacon Solar Energy Project, and the 50-MW Victorville 2 Hybrid Power Project.
China Tries a New Tack to Go Solar
As it moves rapidly to become the world’s leader in wind energy and photovoltaic solar panels, China is taking tentative steps to master another alternative energy industry: using mirrors to capture sunlight, produce steam and generate electricity.
So-called concentrating solar power uses hundreds of thousands of mirrors to turn water into steam. The steam turns a conventional turbine similar to those in coal-fired power plants. The technology, which is potentially cheaper than most types of renewable power, has captivated many engineers and financiers in the last two years, with an abrupt surge in new patents and plans for large power operations in Europe and the United States.
This year may be China’s turn. China is starting to build its own concentrating solar power plants, a technology more associated with California deserts than China’s countryside. And Chinese manufacturers are starting to think about exports, part of China’s effort to become the world’s main provider of alternative energy power equipment.
Yet concentrating solar power still faces formidable obstacles here, including government officials who are skeptical that the technology will be useful on a large scale in China.
Much of the country is cloudy or smoggy. Water is scarce. The sunniest places left for solar power are deserts deep in the interior, far from the energy-hungry coastal provinces that consume most of China’s electricity. Provinces deep in the interior have few skilled workers or engineers to maintain the automated gear that keeps mirrors focused on towers that transfer the heat from sunbeams into fluids.
Concentrating solar power “is not very suitable for China,” wrote Li Junfeng, a senior government energy policy maker, in a detailed e-mail reply to questions this week.
Yet the private sector in China is racing to embrace the technology anyway.
A California solar technology company and a Chinese power equipment manufacturer sign a deal for the construction of up to 2,000 megawatts of power plants using concentrating solar power over the next decade, executives from both companies said this week. That is equivalent to the output of a couple of nuclear power plants. They will start with a 92-megawatt plant in Yulin, a town in a semi-desert area of Shaanxi Province in central China.
The Chinese equipment manufacturer, Penglai Electric, hopes to work with other Chinese manufacturers to drive production costs down precipitously, clearing the way for exports, although these would require further approval from the California licensor of the technology, eSolar.
Eric Wang, the senior vice president for international business development at Penglai Electric, said that manufacturing mirrors, turbines, towers and other equipment in China instead of the United States could cut costs by at least half. That could make concentrating solar power more competitive with other forms of power generation around the world.
China’s Ministry of Science, the Beijing municipal government and the Chinese Academy of Sciences are already building Asia’s first concentrating solar power plant on the outskirts of Beijing, although it is only a pilot operation to generate 1.5 megawatts.
Preparations are also under way for the construction of a 50-megawatt concentrating solar power plant in Gansu Province in northwestern China, said Min Deqing, a renewable energy consultant in Lanzhou, the provincial capital of Gansu.
But while wind power and photovoltaic solar panels have strong backing from China’s political leaders and enormous financing by government-owned banks, concentrating solar power still faces deep-rooted skepticism in senior ranks of the government.
Unlike in the United States, the roots of that skepticism do not lie in concerns about disrupting the habitat of rare species in sunny, desert areas — a worry that may block some attempts to build concentrating solar power plants in the Mojave Desert.
Mr. Li wrote that concentrating solar power works best when cheap water, cheap land and lots of sun are available in the same place — a rare combination in China. Mr. Li also expressed concern that concentrating solar power would prove more expensive per kilowatt-hour generated than photovoltaic solar power, a technology in which China is already the world’s low-cost supplier.
Mr. Li has a lot of influence on these issues. He is a deputy director general for energy research at the National Development and Reform Commission, the top economic planning agency in China. And he is the secretary general of the government-backed Chinese Renewable Energy Industries Association, which helps oversee these industries’ operations in China.
But Mr. Li did say that he saw a limited role for concentrating solar power, particularly in places where it could be combined with other power plants, or where it could be combined with a way to store power overnight. Penglai and eSolar hope to do both.
Water consumption, mainly to condense the steam after it has been used to generate electricity, is another potential weakness of the technology. Water tends to be scarce in deserts, of course. Penglai and eSolar are leaning toward air cooling instead of water cooling, at the price of cutting the efficiency of their plant.
Mr. Gross said the eSolar technology could also be used to create extra heat during the day, with the heat being stored and used to generate power at night — a form of the electricity storage sought by Mr. Li.
Despite the government’s skepticism, renewable energy investors remain enthusiastic about the potential for concentrating solar power projects in China. K. K. Chan, the chief executive of Nature Elements Capital, a renewable energy investment fund in Beijing, said that he had been looking at such deals in recent months after concluding that the valuations for photovoltaic solar projects were unreasonably high, possibly because that technology had such strong government backing.
Mr. Min in Lanzhou said that while there was little data yet on the cost of concentrating solar power, the price tag was likely to fall in China. “Eventually, when 100 percent domestically produced mirrors are used,” he said, “the cost will be lower than solar panel power plants.”