Experimental study and analysis of a novel layered packed-bed for thermal energy storage applications: A proof of concept

Ameen, Muhammad Tahir; Ma, Zhiwei; Smallbone, Andrew; Norman, Rosemary; Roskilly, Anthony Paul

Abstract

This paper presents a study carried out as part of commissioning and testing of world’s first grid-scale 150 kWe Pumped Heat Energy Storage (PHES) demonstration system. The system employs two novel layered packed-bed thermal stores. The present study experimentally investigates one of the stores designated as “hot thermal store”, which has an energy storage density of 1072 MJ/m3 and stores heat at 500 °C and 12 bar. The layered store is an enhancement of a normal packed-bed store and offers a higher degree of thermal stratification. Experiments show that layering results in about 64 % reduction in pressure loss along with yielding considerably narrower thermocline. Round-trip efficiency, storage capacity and utilisation were calculated based on 1st Law analysis considering both simple and layered mode operation at nominal design conditions. Two cycle control scenarios were considered: time-based and temperature-based. In the time-based scenario, the store shows nearly similar performance in both modes. However, in temperature-based scenario, layered mode outperforms. During cyclic operation, layered mode outperforms as it reaches steady-state in merely 3rd cycle, without any loss in efficiency, capacity and utilisation; simple mode yields competitive efficiency but capacity and utilisation deteriorate after each successive cycle and steady-state is achieved in 20th cycle. 2nd Law analysis was additionally performed to gain insight into various losses and their impact on the performance.

Citation

Ameen, M. T., Ma, Z., Smallbone, A., Norman, R., & Roskilly, A. P. (2023). Experimental study and analysis of a novel layered packed-bed for thermal energy storage applications: A proof of concept. Energy Conversion and Management, 277, https://doi.org/10.1016/j.enconman.2022.116648

• Journal Article Type: Article
• Acceptance Date: Dec 20, 2022
• Online Publication Date: Jan 11, 2023
• Publication Date: 2023-02
• Deposit Date: Jan 26, 2023
• Publicly Available Date: Jan 26, 2023
• Journal: Energy Conversion and Management
• Print ISSN: 0196-8904
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 277
• DOI: https://doi.org/10.1016/j.enconman.2022.116648
• Public URL: https://durham-repository.worktribe.com/output/1182391