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Abstract: The use of groundwater for cooling and heating purposes is of interest from both the economical and the ecological perspective. The groundwater heat pump (GWHP) system utilizes groundwater as alternative renewable and clean energy source for space heating and/or cooling, withdraws water from a production well, passes it through a heat exchanger and discharges the water into an injection well. By utilizing the relatively stable temperature of groundwater, GWHP system can achieve a higher coefficient of performance. Due to the utilization of groundwater stored in the aquifer, the assessment of the hydraulic capacity of the aquifer based on numerical groundwater models is always needed for the optimum design and the efficient performance of GWHP. In this paper, numerical methods of underground heat-water transfer, energy balance method and thermal storage method were presented to calculate the capacity of unit area of shallow groundwater aquifer. The model results indicate that the numerical method, which is based on performance efficiency of GWHP, represents the behaviour of groundwater pumping/recharging processes, and serves better than energy balance method and thermal storage method, in addition it has been proven itself that this method has the advantages of energy saving and environmental protection. The calculated capacity is positively related to aquifer thickness. It is found that it is easy for ground water recharge in alluvial and pluvial fan located at the piedmont, while the calculated capacity is relatively smaller compared with that of south-east plain where it is not easy for groundwater recharge. [Copyright &y& Elsevier]

• The replacing of a coal-fired boiler by a GWHP system is investigated. • The operation of each system has been monitored over one-year period. • The boiler has lower investments and covers lower thermal load than the GWHP. • GWHP shows higher economic performance considering Average Energy Price. • GWHP system may be cost effective over traditional boilers for applications. Currently in China, the replacement of coal-fired boilers by clean and renewable energy sources is considered as an essential measure to alleviate air pollution. This paper investigates the thermo-economic performance of replacing a coal-fired boiler by a Groundwater Heat Pump (GWHP) system for a greenhouse, where the GWHP system was constructed to reduce emission and also to provide cooling. The operation of this system has been monitored over a one–year period. The results show that the thermal efficiency factor of the boiler varies in the range of 0.53–0.68 and the Coefficient of Performance (COP) of the GWHP system averages at 4.1 for cooling and at 3.3 for heating. Although the boiler has both lower capital costs and lower operating costs, the analysis of Average Energy Price (AEP) shows that the GWHP system has a higher economic performance, since it has a lower AEP of 0.040 USD /kWh in heating and 0.023 USD/kWh in cooling over an expecting lifetime of 20 years, in comparison to the boiler at 0.052 USD/kWh over a lifetime of 10 years. This indicates that GWHP system may be considered as an alternative over traditional boilers in terms of thermo-economic performance for applications in other places of the world with similar climate condition. [ABSTRACT FROM AUTHOR]