Optimizing the Thermal Performance of an Ice Based Latent Heat Storage System for an External Melt

Abstract

The reasons for the use of an Ice Based Latent Heat Storage System are mainly of economic and environmental nature. Ice Based Latent Heat Storage System systems will improve the energy systems as it reduces load during on-peak hours. It also increase environmental standards as it contributes to the phase-out of synthetic refrigerants. It uses the lower electricity tariff rates available during off-peak hours for state electricity boards of different states. Application of ice based latent heat storage systems are for refrigeration installations which are used in many industries, mainly food industries and HVAC systems. For these applications it is important that they reduce the energy losses and that too should be cost effective improvement. In the present study theoretical investigations of ice based latent heat storage system for an external melt are carried out. The system consists of tank with tubes submerged in water, a condenser, compressor, accumulator and primary as well as secondary refrigeration cycles. A case study is performed to optimize the ice based latent heat storage system. Optimization of the ice that can be formed around the tubes during on-peak hours is done using the energy saving that is achieved by operating the system during off-peak hours. The optimum ice thickness achieved is 30 mm. This amount of ice can be built during on-peak hours of running without any extra cost. The saving achieved by operating during off-peak hours is 30.5% with respect to on-peak hours. To find the energy efficient and economic option and a more efficient design is proposed, having better efficiency then the conventional system. Proposed design will lead to reduction in work of compression and increment in coefficient of performance of the system. An experimental verification is performed on ice based latent heat storage system for industrial applications.