Integration of latent heat thermal energy storage system in a commercial South African cold room

Nearly 60 to 70% of electrical energy in cold storage facilities is used for refrigeration. By infusing Latent Heat Thermal Energy Storage System (LHTESS) with convectional refrigeration systems, electrical costs are reduced. During peak load and Eskom’s load shedding period, the LHTESS releases energy to maintain a compartments’ temperature constant. During normal hours it is charged through a refrigeration system connected parallel to it. This study investigates the integration of an LHTESS in a South African cold room connected on Eskom’s Business rate tariff. A heat load analysis was done to determine the number and initial cost of eutectic plates needed to maintain a temperature of -18°C. Eskom’s tariff plans were used to capture and compare the daily operational costs of a cold room with and without an LHTESS from the year 2021 until 2022. The electrical costs of running a cold room for 17 hours on a business tariff plan is estimated to be R4800, by incorporating an LHTESS operating for 16 hours would reduce this amount to R2260/year. it initially costs R15000 for this system and takes 6 years to recuperate the initial cost. Inexpensive eutectic plates should be designed and manufactured locally for low-cost integration.