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$125.5 Million Solar Technologies R&D Funding Opportunity Announced by US-DOE

DOE describes the categories of Photovoltaic (PV) and Concentrating Solar Power (CSP) research & development proposals which will qualify for grant funds. Linecurrents reviews two CSP generating stations which were US Department of Energy loan guarantee recipients in the last decade.

North section of a 200 kiloWatt (KW) community solar site near Norwood, Colorado. The February 5, 2020 US DOE solar energy research & development funding opportunity includes PV and CSP projects which advance innovative and novel ideas. Linecurr…

North section of a 200 kiloWatt (KW) community solar site near Norwood, Colorado. The February 5, 2020 US DOE solar energy research & development funding opportunity includes PV and CSP projects which advance innovative and novel ideas. Linecurrents photo.

Funding opportunities for:

  • photovoltaic and concentrating solar power (CSP) hardware

  • manufacturing

  • microgrid integration

  • agricultural co-location

  • artificial intelligence

  • innovative small projects

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History of 2 US DOE-supported CSP generating stations reviewed: Crecent Dunes & Ivanpah.

Below are excerpts of a February 5, 2020 announcement by the Solar Energy Technologies Office (SETO) of the United States Department of Energy (DOE) -- Office of Energy Efficiency and Renewable Energy (EERE).

February 5, 2020
Washington, DC

Funding will support advancements in the following areas:

  • Photovoltaics (PV) Hardware Research
    $15 million for 8-12 projects that aim to extend PV system lifetimes and reduce hardware costs of solar systems made of silicon solar cells, as well as new technologies like thin-film, tandem, and perovskite solar cells.

  • Integrated Thermal Energy Storage and Brayton Cycle Equipment Demonstration (Integrated TESTBED
    $39 million for 1-2 projects that will develop a test site to accelerate the commercialization of supercritical carbon dioxide power cycles, a key component of low-cost concentrating solar power plants.

Falling Particle Tower - Example of Supercritical Carbon Dioxide (sCO2) Concentrating Solar Power system. Image: Mehos, Turchi, Vidal, et al, Concentrating Solar Power Gen3 Demonstration Roadmap, NREL/TP-5500-67464, January 2017. Energy.gov.

Falling Particle Tower - Example of Supercritical Carbon Dioxide (sCO2) Concentrating Solar Power system. Image: Mehos, Turchi, Vidal, et al, Concentrating Solar Power Gen3 Demonstration Roadmap, NREL/TP-5500-67464, January 2017. Energy.gov.

  • Solar Energy Evolution and Diffusion Studies 3 (SEEDS 3)
    $10 million for 6-8 projects that will examine how information flows to stakeholders to enable more efficient decision-making about solar and other emerging technologies, such as energy storage.

  • Innovations in Manufacturing: Hardware Incubator
    $14 million for 7-9 projects that will advance innovative product ideas from a prototype to a pre-commercial stage, with an aim for products that support a strong U.S. solar manufacturing sector and supply chain.

  • Systems Integration
    $30 million for 7-11 projects that will develop resilient community microgrids to maintain power during and restore power after man-made or natural disasters, improve cybersecurity for PV inverters and power systems, and develop advanced hybrid plants that operate collaboratively with other resources for improved reliability and resilience.

  • Solar and Agriculture: System Design, Value Frameworks, and Impacts Analysis
    $6.5 million for 4-6 projects that will advance the technologies, research, and practices necessary for farmers, ranchers, and other agricultural enterprises to co-locate solar and agriculture.

  • Artificial Intelligence Applications in Solar Energy with Emphasis on Machine Learning
    $6 million for 8-12 projects that encourage partnerships between experts in AI and solar industry stakeholders to develop disruptive solutions across the value chain of the solar industry.

  • Small Innovative Projects in Solar (SIPS): PV and Concentrated Solar Power (CSP)

    $5 million for 15-20 projects that advance innovative and novel ideas in PV and CSP that can produce significant results within the first year of performance.

 

Supercritical CO2 CSP:
more efficient for converting sunlight into electric energy

Excerpts from US Department of Energy - energy.gov. Full list of references at end of this report.

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Supercritical carbon dioxide (sCO2) power cycles have the potential to reduce the cost of concentrating solar power (CSP) by far more efficiently converting high-temperature solar heat into electricity. 

When carbon dioxide (CO2) is held above its critical temperature and pressure, it acts like a gas yet has the density of a liquid. In this supercritical state, small changes in temperature or pressure cause dramatic shifts in density - making sCO2 a highly efficient working fluid to generate power.

The Solar Energy Technologies Office pursues dramatic cost reductions in technologies to make solar electricity available to all Americans. Next-generation CSP system designs use sCO2 turbine power cycles to more efficiently convert solar thermal energy to electricity and reduce the cost of CSP technology.

Three DOE Offices (Nuclear Energy, Fossil Energy, and Energy Efficiency and Renewable Energy - SETO) are working together to reduce the technical hurdles and support foundational research and development of sCO2 power cycles.

Because sCO2 power cycles work best at very high temperatures and under intense pressure, a CSP system needs receivers and heat exchangers that can withstand these conditions. Heat exchangers contribute up to 60%−70% of the total cost of a CSP sCO2 turbine system, so low-cost, highly efficient exchangers are necessary to help make CSP cost-competitive.

Benefits of CO2 CSP

  • Potential to increase maximum temperature of the heat transfer media to <1,000 deg C .

  • Well-suited for scalability to 10-100 MWe power tower systems.

  • Reduces water consumption compared to current Rankine process.

  • Makes smaller, more dispatchable power plants cost viable.

  • Reduces capital costs by increasing the efficiency of converting sunlight into energy.

 

Nevada CSP powerplant supported by US DOE loan guarantee risks bankrupcty

Crescent Dunes Concentrating Solar Energy Project near Tonapah, Nevada. Electrical generating capacity is 110 megaWatts (MW). U.S. Department of Energy photo.

Crescent Dunes Concentrating Solar Energy Project near Tonapah, Nevada. Electrical generating capacity is 110 megaWatts (MW). U.S. Department of Energy photo.

Excerpts from US Department of Energy - energy.gov. Full list of references at end of this report.

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In power tower concentrating solar power systems, a large number of flat, sun-tracking mirrors, known as heliostats, focus sunlight onto a receiver at the top of a tall tower. A heat-transfer fluid heated in the receiver is used to heat a working fluid, which, in turn, is used in a conventional turbine generator to produce electricity. Some power towers use water/steam as the heat-transfer fluid. Other advanced designs are experimenting with high temperature molten salts or sand-like particles to maximize the power cycle temperature.

. . . Crescent Dunes features a solar receiver that sits atop a tower and absorbs sunlight from over 10,000 mirrors. These mirrors follow the sun over the course of a day and magnify the sun’s power 1,200 times, heating molten salt to high temperatures. This molten salt circulates through the tower and is then used to heat a steam cycle that generates electricity. The plant also features an automated system that controls the flow of molten salt to the receiver.

. . . the molten salt heats more than 60 million pounds of salt each day to reach a consistent 1,050 degrees Fahrenheit. The salt continually circulates in a loop, enabling its reuse by storing it in tanks for use at a later time.

. . . the plant’s energy storage integration delivers solar energy captured during the day to the grid during the late afternoon and evening when the demand for power is at its highest.

. . . Since the molten salt absorbs 90% of the solar energy it receives and is used as both a heat transfer fluid and a storage medium, the plant is highly efficient. Crescent Dunes also eliminates reliance on fossil fuels as a backup energy source, enabling solar to operate as baseload generation and reliably deliver peak-period electricity to more than 75,000 homes in Nevada.

. . . Crescent Dunes is the first deployment of solar power tower technology in the United States that uses molten salt as a primary heat transfer fluid. The heat absorbed by the salt can be stored and produce electricity when required. This enables the plant to generate clean, renewable power during times when direct sunlight is not available. The innovative molten salt storage allows the project to generate power at full load on call (dispatched) for up to 10 hours without any sunlight.

In November 2015, Crescent Dunes successfully reached commercial operation and every year delivers 110 MW of electricity, plus 1.1 gigawatt-hours of storage under a 25-year power purchase agreement with NV Energy, the largest utility in Nevada.

- End of excerpts -

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Owner sues US DOE and plant operator, utility cancels contract

The US Department of Energy finalized a $737 million loan guarantee to Tonopah Solar Energy, LLC to develop the Crescent Dunes Solar Energy Project in September 2011. The site is 14 miles northwest of Tonopah, Nevada on land leased from the Bureau of Land Management - U.S. Interior Department.

Contractual and legal problems developed for Crescent Dunes in October 2019. The Las Vegas Review-Journal reported that Crescent Dunes owner SolarReserve sued the U.S. Department of Energy and plant operator Tonopah Solar Energy.  SolarReserve claims in its lawsuit that US-DOE’s takeover of Tonopah's Board of Managers leaves SolarReserve without board representation, and no voice in decisions such as bankruptcy proceedings, according to reports from multiple energy news sources, including Newsdata.com.

Electric utility NV Energy terminated its 25-year contract to purchase electricity generated at Crescent Dunes October 4, 2010 - (Newsdata.com). The NV Energy - Crescent Dunes Power Purchase Agreement would was to have expired in 2040 - (Mineral County Independent-News). Electricity generated at Crescent Dunes cost NV Energy about $135 per ­megaWatthour - , (13.5 cents per kiloWatthour) compared with less than $30 per MWh today at a new Nevada photovoltaic solar farm, according to January 6, 2020 report by - (Bloomberg Green). Crescent Dunes had been shutdown since April 2019.

 

Mojave Desert CSP generating since 2013

Ivanpah Solar Electric Generating Station - Mojave Desert, California. Electrical generating capacity is up to 400 megawatts (February 2017 data). US Department of Energy image.

Ivanpah Solar Electric Generating Station - Mojave Desert, California. Electrical generating capacity is up to 400 megawatts (February 2017 data). US Department of Energy image.

Ivanpah CSP quick facts

Federal loan guarantees
US Department of Energy issued three loan guarantees for $1.6 billion in total to finance Ivanpah, April 2011.

Generating Capacity

Unit MW
Ivanpah 1 126
Ivanpah 2 133
Ivanpah 3 133
Total 392

Electric utility power purchasers
Pacific Gas & Electric (PG&E) and Southern California Edison.

Energy storage capacity
None.

Land area
3,500 acres on federal land managed by the Bureau of Land Management.

Towers height
459 ft

Number of Heliostats
173,500

Heliostat description
Each heliostat consists of two mirrors.

Receiver type
Solar receiver steam generator.

Receiver inlet temperature
480 F

Receiver outlet temperature
1050 F

Wildlife habitat support (videos)
Bird acoustical deterrent.
Desert tortoise population analysis, juvenile relocation.
- see Stewardship of Natural Resources at Ivanpah videos

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