Abstract: To address the issues of inaccurate thermal storage regulation and low solar fraction in solar heating systems caused by environmental changes in Northwest China, an adaptive mode-switching control strategy based on operational status is proposed for a multi-tank thermal storage system. During the charging process, the system dynamically switches between series and parallel modes according to irradiance levels. In parallel mode, the fmincon optimizer is employed for dynamic flow distribution. During discharging, the system intelligently selects either a high-temperature single tank or an isothermal cluster to supply energy. MATLAB-based modeling and simulation of a residential community in Lanzhou combined with comprehensive economic and environmental evaluation results indicate that compared with the single-tank system, the solar fraction and collector thermal efficiency of the dual-tank system are relatively increased by 4% and 6.1%, respectively; the system net present value is substantially raised by 34.26% relatively, the life cycle cost is relatively reduced by 4%, the static investment payback period is shortened by 0.8 years, and the average annual CO₂ emission reduction is additionally increased by 11.5%. Sensitivity analysis revealed that energy prices and discount rates are the most critical factors affecting economic viability, while subsidy policies can notably shorten the payback period. The study confirms that this multi-tank thermal storage strategy effectively enhances solar heating contributions in regional district heating networks, achieving both strong economic benefits and environmental advantages.