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Renewable Heat on Demand

High-temperature thermal energy storage: a comprehensive study from material investigation to system analysis via innovative component design

Time: Fri 2022-04-01 13.00

Location: M3, Brinellvägen 64A, Stockholm

Video link: https://kth-se.zoom.us/j/68531114425

Language: English

Subject area: Energy Technology

Doctoral student: Silvia Trevisan , Kraft- och värmeteknologi

Opponent: Associate Professor Kurt Engelbrecht, DTU Energy Department of Energy Conversion and Storage

Supervisor: Professor Björn Laumert, Kraft- och värmeteknologi; Rafael Guédez, Energiteknik; Wujun Wang, Kraft- och värmeteknologi

Abstract

High-temperature thermal energy storage could enable widespread exploitation of renewable energy sources, providing the required energy flexibility. Technology and component development is needed to enhance the storage thermo-dynamic performance, and identify key design features. Similarly, system-level integration studies are required to fully understand the techno-economic potential of high-temperature thermal energy storage as integrated into different energy systems. This research work focuses on the development of an innovative packed bed high-temperature thermal energy storage and a multi-level investigation of the potential of this technology. The integration and techno-economic performance of a packed bed thermal energy storage have been studied focusing primarily on its application within concentrating solar power plants. Numerical studies and experimental tests have been conducted assessing the suitability of various coatings to optimize the heat transfer in high-temperature packed beds. A comprehensive design of an innovative packed bed thermal energy storage prototype and its experimental evaluation have been presented. Adapted numerical models have also been validated based on the experimental results, providing the ground for further technology development.The outcomes of this research work show that packed bed thermal energy storage could be a key component in air-driven concentrating solar powerplants, granting high capacity factor while limiting the capital costs. The designed radial flow packed bed storage showed thermal efficiency of about72 % and extremely low-pressure drops. Thermocline degradation control strategies and proper packing have been highlighted as key aspects to target for further development. This research also highlights that accurate boundary conditions should be accounted for when designing packed bed thermal energy storage. Innovative figures of merit, such as the Levelized Cost ofStorage, should be included in the design process. The outcomes of this work show also that coatings could be exploited to modify the particle surface properties while optimizing the heat transfer within packed bed units. In particular, high emissivity coatings could enhance the effective thermal conductivity, while coatings with low thermal emissivity could be exploited as a form of passive thermocline control. Finally, this work testifies that high temperature packed bed could represent a techno-economically valuable energy storage solution. Optimized packed bed designs and their system integration could enable higher renewable penetration, as well as the recovery of a large amount of waste heat from the hard-to-abate and energy-intensive industrial sector.

urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-309660