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The ground-coupled ground-source heat pump (GSHP) system is a common method for shallow geothermal energy exploitation and utilization. GSHP has a great heat exchange rate and wide application range. In order to effectively exploit shallow geothermal energy in the central urban area of Danyang City, Jiangsu Province, based on finite volume method, it is adopted to simulate the amount of recoverable shallow geothermal energy in the study area through ground-coupled heat exchange. The simulation is conducted on the development trend of thermal transport and thermal balance in the study area from early June 2015 to the end of May 2025 to obtain the temperature distribution at different times. Under the presupposed working conditions, with the operation of a ground-coupled GSHP, thermal accumulation occurs in parts of the study area. To mitigate the problem of thermal accumulation, two schemes are proposed: (1) adding auxiliary cooling towers and (2) increasing the amount heated domestic water in spring and autumn. Both schemes mitigate thermal accumulation. For Scheme 1, the total heat supply for shallow geothermal energy in the central urban area of Danyang City in winter is 2.91 × 106 kW, and the total heat release in summer is 3.53 × 106 kW. For Scheme 2, the total heat release in summer is 3.52 × 106 kW and the total heat supply in winter is 2.90 × 106 kW. A ground-coupled GSHP system has significant applicability in the central urban area of Danyang City, where shallow geothermal energy has good exploitation prospects.

Plenty of mathematics researches provide feasibility to calculate the weights of geothermal controlling factors and have been applied in geothermal potential assessment. In order to avoid the disadvantages of subjective and objective weighting calculation methods, an extension theory integrated weighting method was put forward, by combining with the process of AHP and mean variance method. The improved method can reach an agreement on subjective understanding of impact factors’ roles and data-based calculation weights. Then by replacing the point values with intervals, the extension theory was used in classification of geothermal assessment, according to extension judgment matrix. The evaluation results showed perfect performance in classification of impact factors, especially in Wudalianchi area, where 10 out of 11 selected impact factors agreed well with the actual evaluation grades. The study can provide a guidance for primary stage of geothermal investigation including the impact factor selection, weights calculation for impact factors, and the factors’ classification in geothermal assessment.