PCM-STORE - PCM-based low-temperature Thermal Energy Storage for a more sustainable food industry

PCM-STORE gathers dairies, fish industries, food processing plants, technology suppliers and power grid operators to work towards a common goal: Solving energy storage challenges in support of a more energy-efficient industrial future. More renewable energy means greater variations in the electricity grid, hastening the need to develop more energy-efficient industry. Better energy storage solutions can reduce peak power demands for intermittent processes, facilitate load shifting, and hedge against any shortage in energy supply. Compared to traditional storage methods for electricity, thermal energy storage (TES) stores large amounts of thermal energy at both low- and high temperatures more efficiently and at much lower cost. Although highly relevant for Norwegian food industries, the competence on cold TES (CTES) is still limited in Norway. To meet this challenge, PCM-STORE will develop low-temperature TES systems based on phase change materials (PCM) for industrial cooling and freezing processes. Three case studies representing different temperature ranges are identified as potential candidates for implementation of PCM-CTES: industrial batch freezing processes, cold storage in food processes and refrigerated display cabinets. Application of PCMs requires a thorough understanding of limiting phenomena such as supercooling, low thermal conductivity, phase separation and low heat transfer rate. PCM-STORE will combine detailed numerical modelling of these phenomena, dynamic system modelling of the PCM-CTES units integrated in selected industrial applications, experimental validation of the models as well as lab-scale pilot demonstrations. Industrial partners are at the heart of PCM-STORE. Utilization of PCM-CTES will enable partner industries to cover their peak cooling while reducing peak power demands, increase cooling capacity, and decrease food waste. This will reduce both operational and investment costs, leading to a more sustainable Norwegian industry. Since the project started, a number of commercial PCMs have been characterized in our lab facilities. This is both to develop competences in PCM characterization and to establish a database of relevant PCMs that could be directly implemented in relevant applications for PCM-STORE's partners. This work has been carried out jointly with partner University of Pau (France). A new numerical model of the PCM-pillow-plate heat exchanger has been developed to represent the actual behaviour of the PCM cold storage in dynamic system models. This work has been carried out together with partner TLK-Thermo (Germany), using experimental data from SINTEF-NTNU lab facilities. The new component will be key to investigate the user partners' industry processes and identify the most beneficial integration path for the PCM-CTES technology. Through site visits and regular dialogue, we have started the extensive modelling of industrial processes from our partners Norsk Kylling, Pelagia and Rørosmeieriet. These models, together with process and energy data showing the dynamic behaviour of their energy needs will allow us to investigate where PCM-CTES would be best integrated. For most of the user partners, peak shaving remains the priority target for PCM-CTES implementation. Two new types of heat exchangers, including one provided by Alfa Laval, are in the design phase to be experimentally tested with PCM in order to investigate novel PCM-CTES configurations which could contribute to lower the current investment costs for implementing PCM-CTES technologies.

Energy storage is vital for future energy efficient industries to supply peak power demands for intermittent processes, to facilitate load shifting, and to hedge against shortage in energy supply. Thermal energy storage (TES) enables storing large amounts of thermal energy at both low- and high temperatures more efficiently and at significantly lower costs than electrical energy storage. There is a great need for low-temperature TES in the food industry with high and highly varying cooling and freezing demands. PCM-STORE addresses this challenge by developing low-temperature TES systems based on phase change materials (PCM) for industrial cooling and freezing processes. Although highly relevant for Norwegian food industries, the competence on cold TES (CTES) is currently limited in Norway. Three case studies representing different temperature ranges are identified as potential candidates for implementation of PCM-CTES: industrial batch freezing processes, cold storage in food processes, and refrigerated display cabinets. Application of PCMs requires thorough understanding of the phenomena limiting the application of PCMs, such as supercooling, low thermal conductivity, phase separation and low heat transfer rate. PCM-STORE will combine detailed numerical modelling of these phenomena, dynamic system modelling of the PCM-CTES units integrated in selected industrial applications, experimental validation of the models as well as lab-scale pilot demonstrations. PCM-STORE is a joint effort gathering various industrial actors: dairies, fish industries, food processing plants, technology suppliers and power grid operators. Utilization of PCM-CTES will enable the partner industries to cover their peak cooling while shaving peak power demands, to enhance cooling capacity, and to reduce food losses. This will reduce both operational and investment costs and enable more stable operation of the cooling system, leading to a more sustainable Norwegian industry.