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
- Thermal Energy Storage (TES) Marketon August 5, 2020 at 3:40 am
WiseGuyRerports.com Presents “Global Thermal Energy Storage (TES) Market 2020 by Company, Regions, Type and Application, Forecast to 2025” New Document to its Studies Database The global Thermal ...
- Global Energy Storage Systems Market Outlook to 2025 - Market Expected to Proliferate During the Forecast Period, Despite the Outbreak of COVID-19on August 4, 2020 at 10:00 am
The "Global Energy Storage Systems Market Outlook to 2025" report has been added to ResearchAndMarkets.com's offering. Improving energy ...
- Sustainable Methods of Thermal Energy Storage to Bring Drastic Transformationon August 4, 2020 at 5:51 am
Market players are adopting more sustainable ways of storing thermal energy than before. Many startups have entered the market and introduced sustainable ways of thermal energy storage. Companies are ...
- Thermal Energy Storage Market is Expected to Grow at an Estimated CAGR of 12.6% during 2020-2027 | Grand View Research, Inc.on August 1, 2020 at 4:15 am
Market Research And Consulting.” According to report published by Grand View Research, The global thermal energy storage ...
- Impact of COVID-19 on the Energy Storage Systems Industry, 2025on July 31, 2020 at 5:01 pm
The "Global Energy Storage Systems Market Outlook to 2025" report has been added to ResearchAndMarkets.com's offering. Improving energy storage economics, innovations in financing and business models, ...
- Cold Cash In Cold Storageon July 30, 2020 at 8:00 am
After reeling from the sight of empty store shelves and regional shortages of various personal care and food products due to the COVID-19 pandemic, investors see the potential for consolidation and ...
- World Energy Storage Systems Market 2020-2025: Focus on Batteries, PSH, TES, FES and Others - ResearchAndMarkets.comon July 30, 2020 at 4:09 am
The "Global Energy Storage Systems Market Outlook to 2025" report has been added to ResearchAndMarkets.com's offering. Improving energy storage ...
- DOE funds power-plant energy storage, wastewater analysis research projectson July 29, 2020 at 9:05 am
DOE will fund two academic-industry projects with Lehigh University's Energy Research Center: A project to improve operating efficiency and system reliability of power plants in the context of plant ...
- Norwich Technologies wins U.S. Department of Energy grant for solar power research and developmenton July 27, 2020 at 6:34 am
WHITE RIVER JUNCTION, VERMONT, July 20, 2020 –Norwich Technologies announced today that the company has been awarded a $1.1 million dollar U.S. Department of Energy (DOE) grant to develop a low ...
via Bing News