Thermal Energy Storage Systems
Thermal energy storage systems (TESS) store energy in its thermal form and rely on the transfer of heat. This approach differs from battery energy storage systems (BESS) that typically involve chemical reactions inside lithium-ion batteries for energy storage. That said, both TESS and BESS share the same basic purpose—to store excess energy for later use.
Types of Thermal Energy Storage
The U.S. Department of Energy’s “Technology Strategy Assessment” (July 2023) categorizes thermal energy storage into three groups: sensible, latent, and thermochemical.
1. Sensible involves increasing the temperature of molten salt or a solid medium like rock.
2. Latent relates to the heating and/or cooling of a “phase change material” like metal alloy.
3. Thermochemical, according to the DOE’s report, involves “storing energy in reaction heat, such as in reduction/oxidation cycles.”
Benefits of Thermal Energy Storage Systems
One of the obvious benefits of thermal energy storage is the lack of reliance on lithium-ion batteries, thereby overcoming certain supply chain bottlenecks and reducing the nation’s reliance on offshore manufacturing.
The DOE’s report points out additional benefits of TESS:
“TES systems provide many advantages compared with other long-duration energy storage (LDES) technologies, which include low costs, long operational lives, high energy density, synchronous power generation capability with inertia that inherently stabilizes the grid, and the ability to output both heat and electricity.”
—From the U.S. Department of Energy’s report: “Technology Strategy Assessment, Findings from Storage Innovations 2030 Thermal Energy Storage, July 2023”
Land-Related Aspects of TESS Projects
Nearby landowners may find comfort in knowing that TESS projects do not utilize lithium-ion batteries. That said, thermal energy likely involves high temperatures that could stir up negative publicity and local pushback. TESS project developers should also be aware of the following land-related challenges:
Semi-permanence: Compared to other types of projects, energy storage tends to be viewed as a long-term proposition. Landowners may have reservations about tying up their land for multiple generations.
Density and location: Energy storage sites may only require a few acres, but this land will be heavily populated with high-value, specialized equipment. Selecting the right location is key for maximizing return on investment and avoiding risk.
State and local issues: Statutes, ordinances, and pending legislation vary depending on the jurisdiction. Gaining a clear understanding of state and local requirements is essential for ensuring successful projects.
Contact Trigen to request on-the-ground support for thermal energy projects.