A Study on the Suitability of Operating Strategies for PV/T-Medium-to-Deep-Ground-Source Heat Pump Heating Systems Based on Peak-and-Off-Peak Electricity Rates - Dong Wei; Yu-ping Zhang; Quan-hui Liu; Yi-chao Zhao; Hao Wu; Sheng-ji Xu; Yu Cao; Jia-yuan Li; Ling-ling Bao (Applied Geophysics, 2026)