U.S. Department of Energy

High-Efficiency Thermal Energy Storage System for CSP

ANL logo Photo of a black and white porous material magnified 50 times by a microscope.

Microstructure of the highly thermal conductive foam that will be used for the prototype TES system.
Image from ANL

Argonne National Laboratory and project partner Ohio Aerospace Institute, under the National Laboratory R&D competitive funding opportunity, will design, develop, and test a prototype high-temperature and high-efficiency thermal energy storage (TES) system with rapid charging and discharging times. By increasing the efficiency of TES systems, this project aims to lower the capital costs of concentrating solar power (CSP) systems.


The research team is developing and evaluating a novel approach for TES at temperatures greater than 700˚C for CSP systems. The approach uses high thermal conductivity and high-porosity graphite foams infiltrated with a phase change material (PCM) to provide TES in the form of latent heat.

The goals for this project are to:

  • Model the proposed TES system concept and ensure it meets the performance and cost targets
  • Develop the necessary technologies to construct a prototype
  • Build and test a laboratory-scale TES prototype
  • Use the data gathered from prototype testing to predict the performance of a full-scale TES system


TES based on latent heat storage can potentially provide higher volumetric TES capacity when compared to sensible energy storage systems. Infiltrating the foam with PCM compensates for the relatively low conductivity of the PCM and allows for quick, even distribution of thermal energy into the PCM, leading to rapid charge/discharge cycles. Using this concept, the team will design a TES system using PCM with high storage densities and high specific thermal conductivities, while maintaining a low thermal time constant. The enhanced thermo-physical properties of the PCM system using graphite foam will allow for significant reduction in charging and discharging times when evaluated against other PCM storage options. The potential high storage density of this system will also allow for the possibility of a smaller TES system volume, thereby lowering the capital costs.

Publications, Patents, and Awards

At this time, this project does not have published articles, patents, or awards.

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Learn about other DOE competitive awards for concentrating solar power research that are in progress.