A Study of Geothermal Heat Pump and Standing Column Well Performance

Standing column wells can be used as highly efficient ground heat exchangers in geothermal heat pump systems, where hydrological and geological conditions are suitable. A numerical model of groundwater flow and heat transfer in and around standing column wells has been developed. This model has been used in a parametric study to identify the most significant design parameters and their effect on well performance. For each case in the study, performance has been evaluated in terms of minimum and maximum annual temperatures and design well depth. Energy consumption and annual costs have also been calculated. Groundwater “bled” from the system is one of the most significant parameters a system designer can use to improve well performance for a given load. The effects of bleed rate, well depth, and rock properties on heat transfer and energy consumption are discussed.