Session: 03-04 Sensible Energy Storage

Paper Number: 106662

106662 - Fabrication, Modeling, and Testing of a Prototype for Particle Thermal Energy Storage Containment 

Increasing penetration of variable renewable energy resources requires the deployment of energy storage at a range of durations. Long-duration energy storage (LDES) technologies will fulfill the need to firm variable renewable energy resource output throughout the year. Conventional electrochemical batteries (e.g., lithium-ion) are uneconomical in this role due to high energy capacity costs. Thermal energy storage (TES) is one promising technology for LDES applications because of its siting flexibility and ease of scaling. Particle-based TES systems use low-cost solid particles that have higher temperature limits than the molten salts used in traditional concentrated solar power systems. A key component in particle-based TES systems is the containment silo for the high-temperature (> 1100 °C) particles. This study combined experimental testing and computational modeling methods to design and characterize the performance of a particle containment silo for LDES applications.

A containment silo prototype was built at laboratory scales and used to validate a congruent transient finite element analysis (FEA) model. The validation compared the actual and predicted temperature profile through the prototype over 6 days as the particles cooled from their initial temperature. The performance of a commercial scale (> 5 GWh_th) was then characterized using the validated model. The transient FEA model was put through several charge-discharge cycles to mimic a possible operating schedule. The commercial-scale model predicted a round-trip thermal efficiency above 95% after 5 days of storage with a design storage temperature of 1200 °C. Insulation material and concrete temperature limits were considered as well. The sensitivity of this metric was examined to different assumed ambient temperature conditions and operating schedules. The round-trip thermal efficiency was minimally impacted by changes in ambient temperature conditions but did have significance for the design of the insulation due to material temperature limits. The validation of the methodology means the FEA model can simulate a range of scenarios for future applications. This work supports the development of a promising LDES technology with implications for grid-scale electrical energy storage, but also for thermal energy storage for industrial process heating applications.

Presenting Author: Jeffrey Gifford Colorado School of Mines

Presenting Author Biography: I am a PhD Candidate in the Advanced Energy Systems program at the Colorado School of Mines. My dissertation research focuses on using computational tools to answer key questions about the performance, economics, and operations of particle-based thermal energy storage components and systems for long-duration energy storage applications. Additionally, I have technical interests in the research and development of fuel cell and electrolysis systems, solar fuel production, and long-duration thermal energy storage; which are/have been the focus of my research at the National Renewable Energy Laboratory (NREL) for the past four years. I also have an interest in energy policy and economics and how my engineering background can be complemented by these other topics.