A large-scale seasonal ice storage cooling system using an ice pond has been designed, built, and operated at a commercial office building complex in Princeton, NJ. Ice is produced as artificial snow during winter using ski-slope snow machines and naturally cold outside air. During the cooling season, cold melt water is circulated through the cooling system of a 130,000 ft2(12,0002) three-floor office building. The design is discussed and data from the first full year of operation are presented. The annual coefficient of performance is 10, based on total cooling energy delivered and total electricity consumed by snow machines in the winter and by circulating pumps in the summer.Units: Dual