Using existing cold stores as thermal energy storage.

The industrial cold stores can act as thermal energy stores that can store the energy as passive thermal energy. The cold stores have intentions to contribute with flexible consumption but need some knowledge about the potential. By cooling the cold stores and the goods further down when the energy is cheaper, there is a potential of an attractive business case, especially if the elspot price can be predicted further into the future. The cold stores can provide flexibility by load shifting to the energy grid by moving their extensive energy use to off-peak hours. To fulfill the potential, it is necessary to measure some data in the cold stores to be able to control them and ensure food safety. A case study was tested and revealed that by cooling further in periods of low-cost electricity could results in 30% savings. With proper elspot price forecasting this percentage could reach up to 40%. Theoretically, by utilizing the full capacity of cold stores in Denmark for thermal energy storage, it is possible to use 2% of the average wind electricity production.