Seasonal aquifer storage of wlnter-chil led groundwater is a potentially economical source of chilled water for district cool ing systems. During winter, groundwater would be pumped to the surface, cooled to near freezing using ambient winter air, and injected into a second well for seasonal storage.

Feasibility analysis of any district cooling system requires initial optimization of variables, including building load characteristics, market competition, distribution alternatives, and total system economics. Integration of seasonal aquifer storage with district cooling increases the complexity of the initial optimization analysis. The interaction of major variables in analyzing the feasibility of seasonal aquifer storage for district cooling systems is addressed, based on a feasibility study in downtown St. Paul, Minnesota.

In Minnesota and in similar climates, district cooling using aquifer storage can be economically feasible in areas undergoing substantial new development and/or redevelopment. However, the system was not economically competitive with the status quo in the already developed downtown St. Paul area.

Units: I-P