This resource suggests that the frost line in Calgary is about nine feet underground: http://www.urecon.com/applications/municipal_ambient_below.h... . That's the depth at which the ground temperature is above freezing for the whole year. That means that a heat pump can exchange heat via pipes buried nine feet under your property. Technologically, it's extremely feasible. Whether or not it makes sense for you will depend on economic factors, of course.