Performance Enhancement of Cold Thermal Energy Storage System using Nanofluid Phase Change Materials

Abstract

Cooling Thermal Energy Storage (CTES), for large air conditioning system is becoming paramount in maintaining building comfort, at the expense of huge energy usage. Water based Ethylene Glycol (EG) is used as Heat Transfer Fluid (HTF) with Phase Change Material (PCM) nodule. EG25 of 25% concentration by volume is added into HTF so that the freezing point falls below 0.0 ?C, and PCM could solidify from liquid to store latent energy. Energy use needed to be prudent and hence, nanofluid CuO was explored for heat transfer enhancement to current CTES system. This paper is to compare the efficiency of heat transfer of energy storage using PCM immersed in EG25 solution and nanofluid CuO. Numerical approach and simulation are conducted to study the improvement of specific heat, latent heat and the behaviour of energy release during melting. The result obtained has proven that nanofluid, EG based mixture is capable of increasing thermal conductivity, enhancing heat transfer. This increases the coefficient of performance and overall efficiency of thermal energy storage.