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• A numerical model is proposed and validated to predict ground temperature profiles. • Three typical meteorological year databases are compared to provide the weather parameters for the numerical model. • Two-harmonic analytical correlation (THAC) with high accuracy is introduced to obtain ground temperature rapidly. • THACs of main cities in two climate regions in China are provided on the standard condition. • THACs of all types of soil can be derived according to the developed universal correction formulas and the standard THACs. The lacking of ground temperature measurement data has been preventing the development of underground engineering in China. Therefore, this paper proposed and validated a numerical prediction model that comprehensively considered the effects of short-wave solar radiation, long-wave radiation, latent evaporation energy, heat convection, heat conduction, soil freezing and thawing latent heat on ground temperature. Three frequently-used typical meteorological year databases were used to provide the weather parameters for the numerical model. Comparison of three city cases showed that the model using the "Chinese typical year weather" performed best in accuracy. Moreover, due to the much calculation time required for the numerical model, the two-harmonic analytical correlation (THAC) with higher accuracy than Kusada correlation and Baggs correlation was introduced to obtain ground temperature rapidly. Considering the variety of soil types, the universal correction formulas about the relationship between the THAC coefficients and the soil thermal diffusivity were developed through a series of typical city cases. Simultaneously, THACs of main cities in two climate regions corresponding to soil thermal diffusivity of 8.13*10-2 m2/day were provided as the standard THACs. The THACs of other types of soil were proved to be derived according to the universal correction formulas and the standard THACs. [ABSTRACT FROM AUTHOR]

• China has abundant SGE resources but the utilization of which remains still low. • SGE is mainly used for building heating and cooling via GSHP technology. • Energy efficiencies of GSHP systems are generally not high in China. • Some measures can be considered to enhance the utilization efficiency of SGE. • AI technology will be a significant measure for SGE resource evaluation. This paper summarized the shallow geothermal resources within a depth of 200 m in China. This geothermal resource is divided into five regions based on the geological structures, geomorphology, geology, and hydrogeology. The recoverable amount of shallow geothermal energy (SGE) is equivalent to 7 × 1012 kg of standard coal in a survey area of 1.69 × 105 km2, 60% of which is distributed in the mid-eastern region of China. SGE is mainly used for building heating and cooling via ground source heat pump (GSHP) technology since 1990s. The coefficient of performance (COPs) of the GSHP system exhibits large regional differences, and the energy utilizing efficiencies of GSHP systems are not high. The utilization rate of SGE is still low compared with those of other forms of renewable energy. Some measures, including a standardized and simplified management system, a feasible evaluation and utilization plan, modified technology and standards, an intelligence environmental impact assessment, and intelligence monitoring, can be considered to enhance the utilization efficiency of SGE. [ABSTRACT FROM AUTHOR]