Energy Storage for Effic ient Energy Utilization in Buildings

ABSTRACT Phase change materials (PCMs), which melt and solidify at a specified temperature range, can be employed effectively to store energy as latent heat of melting in a large number of applications. They can be used to increase thermal mass of buildings by mixing them with the building materials such as gypsum or concrete. Our constructed research facilities show that the application of PCM could significantly reduce variation in the indoor temperature of buildings by absorbing heat during daytime and releasing it at night. The objective of this paper was to show experimentally and through a computer simulation using SUNREL that PCM impregnated in building materials can provide thermal energy storage benefits. For these simulations Paraffin (RT21), which is a mixture of paraffin has been used as the PCM because of its desirable thermal and physical attributes including its melting temperature of 21 o C, which is close to human comfort temperature. The simulated results show that the use of PCM can effectively reduce the daily fluctuations of indoor air temperatures and maintains it at the desired comfort level for a longer period of time.