Energy storage is crucial for taking full advantage of solar power, which otherwise suffers interruptions from cloudy skies and nightfall. In the past few years, concentrating solar power plants have begun producing additional electricity at night and during peak demand periods by using stored heat energy to propel a steam turbine.
Current thermal energy storage systems rely on materials that store less energy per kilogram, requiring more material at a greater cost to meet energy storage requirements.
Now, researchers at the U.S. Department of Energy’s (DOE’s) Argonne National Laboratory have designed an inexpensive thermal energy storage system that will be significantly smaller and perform more than 20 times better than current thermal systems.
With funding from DOE’s SunShot Initiative, the Argonne team is building a pilot-scale prototype of their high-efficiency latent heat thermal energy storage system (LHTES) for testing. The SunShot Initiative is a national collaborative effort to make unsubsidized solar energy cost-competitive with other forms of electricity production by 2020.
Argonne’s thermal energy storage system relies on a “phase-change” material that melts as it stores thermal energy and releases energy as it re-freezes — similar to the charge-discharge cycle in a battery.
Inexpensive salts like rock salt (sodium chloride) can be used as phase-change materials, but their use in existing thermal storage systems is limited because of the poor thermal conductivity of the salts.
However, the Argonne LHTES system drastically improves the conductivity of these salts by integrating them with a high-conductivity graphite foam. This combination reduces the overall amount of material needed to build the system and its cost, while making the thermal energy transfer significantly more efficient and still providing up to 8 to 12 hours of energy storage — a typical night of storage for a concentrating solar power plant.
“Phase-change materials tend to have low conductivity but meet the heat energy storage requirements,” said Dileep Singh, leader of Argonne’s Thermal-Mechanical Technologies group. “High-conductivity graphite foam meets the conductivity requirements, so we thought: why not combine the two?”
The porous graphite foam traps the salts in pores, facilitating rapid melting and freezing. The team demonstrated that this rapid phase change holds up over time. After building and testing an initial prototype about the size of a blender, the team is now scaling up the prototype size by 50 times.
Although still smaller than a full-scale power plant system, the pilot-scale modular system will be tested this fall and could expand on applications, such as providing back-up power on a microgrid or storing waste heat from another energy source. The pilot system will also further improve 3-D thermal modeling used for estimating performance and planning the design of a full-scale system.
“We are looking at developing the full-scale power plant system as a modular system, and the pilot-scale system we are building this year can actually be used as one module within a full-scale system that is made of many modules stacked or organized together,” said Argonne mechanical engineer Wenhua Yu. “Therefore, the performance characteristics we will measure from testing the pilot can directly reflect those of a power plant system.”
The full-scale design is expected to meet the needs of current power plants that operate steam turbines at about 450 to 600 degrees Celsius (850-1100 degrees Fahrenheit) using magnesium chloride as the storage medium. When advanced supercritical carbon dioxide turbines — which are more efficient than steam turbines but operate at a hotter 700 degrees Celsius (1,300 degrees Fahrenheit) — come online, the same design can be used with sodium chloride.
This work is supported by the DOE SunShot Initiative.
The SunShot Initiative is a collaborative national effort that aggressively drives innovation to make solar energy fully cost-competitive with traditional energy sources before the end of the decade. Through SunShot, the DOE supports efforts by private companies, universities, and national laboratories to drive down the cost of solar electricity to $0.06 per kilowatt-hour. Learn more at energy.gov/sunshot.
The Latest on: Thermal energy storage
via Google News
The Latest on: Thermal energy storage
- Energy Storage Research Center opens in Birminghamon July 17, 2019 at 1:31 pm
The center’s aim is to speed the development of the next generation of clean and sustainable energy storage technology. It will test chemical, mechanical and thermal energy storage systems. It will ... […]
- Thermal Energy Storage Market - Growth Opportunities in Emerging and Established Marketson July 15, 2019 at 6:37 am
San Francisco, CA -- (SBWIRE) -- 07/15/2019 -- Thermal energy storage systems consist of an insulating medium or combination of media that can hold on to captured heat for long periods. Thus, thermal ... […]
- Liquid-air storage offers cheapest route to 24-hour wind and solaron July 10, 2019 at 8:53 am
So in a way we are replacing decommissioned thermal power generation with energy storage.” While the initial string of LAES plants will be used to balance the grid, they could also be built at wind or ... […]
- Thermal Energy Storage Marketon July 5, 2019 at 4:46 am
A new research report titled, 'Global Thermal Energy Storage Market' has been added to the vast repository The Insight Partners. The intelligence report provides an in-depth analysis of the global ... […]
- EPRI to Lead $5 Million DOE/NETL Project to Test Concrete Thermal Energy Storage Technologyon July 1, 2019 at 7:14 am
PALO ALTO, Calif., July 01, 2019 (GLOBE NEWSWIRE) -- The Electric Power Research Institute (EPRI) has been selected by the U.S. Department of Energy (DOE) and the National Energy Technology Laboratory ... […]
- Which energy storage technology is going to power Australia’s future?on June 28, 2019 at 1:28 am
Recent events in Australia indicate a growing appetite for renewable energy and energy storage in the energy sector. Pumped hydro, thermal energy storage, hydrogen—which form of storage will reign ... […]
- Thermal Energy Storage Market Covering Trends, Market Share and Forecast to 2020on June 27, 2019 at 8:27 am
Albany, NY -- (SBWIRE) -- 06/27/2019 -- In order to study the various trends and patterns prevailing in the concerned market, Market Research Reports Search Engine (MRRSE) has included a new report ... […]
- MA Cold Storage Facilities Gain 1.3 MW of Thermal Energy Storageon June 13, 2019 at 9:34 am
(Photo: A frozen food warehouse that has Viking Cold Solutions thermal energy storage systems. Credit: Viking Cold Solutions) Viking Cold Solutions installed eight behind-the-meter thermal energy ... […]
- Thermal Energy Storage (TES) Market, 2024 - Evolving IoT Standard and Upcoming Smart Cities to Fuel Large Scale Adoptionon June 11, 2019 at 6:10 am
Dublin, June 11, 2019 (GLOBE NEWSWIRE) -- The "Thermal Energy Storage (TES): Global Market Analysis, Trends, and Forecasts" report has been added to ResearchAndMarkets.com's offering. This report ... […]
via Bing News