A commercial-scale ice pond refrigeration system was designed and built a Tokachi, Hokkaido, to store 180 metric torts of potatoes until next July following the harvest. The system was capable of producing an ice pond of 1200 m3 capacity of dimensions 26m in length, 18m in width, and 3.5m in depth. The ice-making performance of the system was tested during two winter seasons. The final height of the ice pond was about 3.1m, and its volume was approximately 970m3. Although the expected ice volume was 1200m3, the two consecutive relatively mild winters of the testing period prevented from attaining the optimum dimensions of the ice pond. The average voltlmetric thermal purity of ice, as measured by the ratio of latent heat of fusion of produced ice per unit volume to that of pure ice, was in the range of 0.76 to 0.78 which showed relatively high thermal quality of the ice. The average electric cost of producing an unit volume of ice was 100 yen/m3 which demonstrated the cost-effectiveness of the system.HomePageKeywords: ice pond refrigeration, potatoes, storage, ice making