Integration of standing column wells in urban context: A numerical investigation-case in the City of Montreal

Abstract

While the use of new technologies with low greenhouse gas emissions is growing quickly, ground source heat pump systems offer net advantages for urban environments. Standing column well, which exploits groundwater as a heat transfer fluid, requires less space and is less expensive than traditional closed-loop ground heat exchangers. However, a lack of information regarding standing column well is observed, especially in terms of interference with neighboring systems. A semi-regional finite element model was thus developed to emulate the thermal and hydraulic behavior of several standing column wells operated in an area of the City of Montreal. Five municipal and residential buildings were considered, with a total of 14 standing column wells and 5 injection wells. Numerical simulations indicate that infrastructure, such as buildings and roads, have a greater effect on increasing ground temperature than standing column wells. Results show the viability of each system over 10 years of operation without noticeable performance degradation and environmental impacts. Results also indicate that thermal modifications in the ground have a wider and greater extent than hydraulic modifications and decreases rapidly with depth. The study demonstrates that the operation of those systems in an urban context is viable in short and mid-term. • A semi-regional model emulated the impact of standing column wells in an urban area. • Operation of standing column wells in dense urban area is possible. • Results indicated no performance degradation or noticeable environmental impacts.