一种新型钻孔热能储存系统的实验研究：通过低品位能量的有效分配提升性能

Abstract Borehole Thermal Energy Storage (BTES) systems play a crucial role in decarbonizing building energy systems, yet face significant limitations, including high heat losses, extended preheating periods, and structural inefficiencies. This study introduces an innovative BTES configuration that addresses these challenges through a partitioned operational mechanism and a High- & Low-Grade Reservoirs layout. Unlike conventional radially series-connected systems, our design strategically utilizes multi-grade energy inputs to optimize thermal performance. Through comprehensive sandbox experiments comparing three distinct configurations (High- & Low-Grade Reservoirs, Single Reservoir-Parallel, and Single Reservoir-Series), we demonstrate that parallel connections outperform series configurations by 19 % in heat storage capacity during seasonal storage. Integrating a low-grade energy barrier in peripheral areas increased the charging rate by up to 39 % and storage capacity by 12–15 % during the charging phase while enhancing heat storage by 28 % and reducing exergy destruction by 30 % during seasonal storage. Energy density decay in all configurations follows a precise logarithmic distribution (R 2 ≥ 0.998), with our innovative design extending storage duration by up to 33.8 days. This research reveals the evolution of subterranean temperature fields within a non-uniform heat storage mechanism and provides essential data for advancing BTES applications in net-zero carbon building energy systems. The proposed configuration represents a significant advancement in sustainable energy integration by synergistically optimizing energy collection, storage, and supply within building thermal systems.