10 - Standing column wells

Abstract

Standing column well (SCW) systems present a strong potential for energy savings, especially in dense urban areas with suitable geological conditions where lack of space constitutes an impediment to the use of closed-loop systems. This chapter aims at presenting some design considerations and recent advancements relative to the thermal, hydraulic, and chemical simulation of SCWs and identifies specific research needs to foster their use. It is shown how a thermal resistance and capacity model can assess the performance of a hybrid system operated under different bleed ratios in a fractured aquifer. Additionally, this chapter shows how to perform coupled thermo-hydrogeochemical simulation to predict the dissolution and precipitation of calcite that occurs along the well as a function of operating conditions. The approach helps to foresee possible operation problems with the SCW and to select suitable mitigation measures to sustain long-term performance of SCW.