TY - JOUR
T1 - A comprehensive review on pit thermal energy storage: Technical elements, numerical approaches and recent applications
AU - Xiang, Yutong
AU - Xie, Zichan
AU - Furbo, Simon
AU - Wang, Dengjia
AU - Gao, Meng
AU - Fan, Jianhua
PY - 2022/11/25
Y1 - 2022/11/25
N2 - Pit thermal energy storage (PTES) is one of the most promising and affordable thermal storage, which is considered essential for large-scale applications of renewable energies. However, as PTES volume increases to satisfy the seasonal storage objectives, PTES design and application are challenged. These difficulties trigged an interest in PTES investigations. This paper aims to identify the success factors and research gaps of PTES by an up-to-date evaluation of 160 recent publications. Existing technical elements that affect PTES thermal properties inclusive geometry design, inlet/outlet design, cover design, and materials, are outlined in depth. Numerical studies are categorized in terms of their mathematical theory and research purposes for a systematic discussion. The current application status of PTES systems worldwide is summarized from four aspects: storage material, geological design, operation strategy, and storage duration. For projects in operation, special attention is given to gathering and comparing operational data on solar fraction, storage efficiency, storage cycle, and PTES tem-perature. This review outlines the progress and potential directions for PTES design and numerical studies by identifying the research gaps that require further effort.
AB - Pit thermal energy storage (PTES) is one of the most promising and affordable thermal storage, which is considered essential for large-scale applications of renewable energies. However, as PTES volume increases to satisfy the seasonal storage objectives, PTES design and application are challenged. These difficulties trigged an interest in PTES investigations. This paper aims to identify the success factors and research gaps of PTES by an up-to-date evaluation of 160 recent publications. Existing technical elements that affect PTES thermal properties inclusive geometry design, inlet/outlet design, cover design, and materials, are outlined in depth. Numerical studies are categorized in terms of their mathematical theory and research purposes for a systematic discussion. The current application status of PTES systems worldwide is summarized from four aspects: storage material, geological design, operation strategy, and storage duration. For projects in operation, special attention is given to gathering and comparing operational data on solar fraction, storage efficiency, storage cycle, and PTES tem-perature. This review outlines the progress and potential directions for PTES design and numerical studies by identifying the research gaps that require further effort.
KW - Pit thermal energy storage
KW - Recent applications
KW - Floating cover
KW - Liner and insulation material
KW - Simulation approaches
KW - DISTRICT-HEATING SYSTEMS
KW - UNDERGROUND WATER PIT
KW - INSULATION MATERIALS
KW - SEASONAL STORAGE
KW - RADIAL DIFFUSERS
KW - CONDUCTIVITY
KW - SIMULATION
KW - STRATIFICATION
KW - OPTIMIZATION
KW - INTEGRATION
U2 - 10.1016/j.est.2022.105716
DO - 10.1016/j.est.2022.105716
M3 - Review Article
SN - 2352-152X
VL - 55
SP - 1
EP - 30
JO - Journal of Energy Storage
JF - Journal of Energy Storage
M1 - 105716
ER -