Abstract
A phase change material (PCM) alters the heat flow across the building envelope by absorbing and releasing heat in response to cycling ambient temperatures. The benefit of a PCM is reduction in heating and cooling loads and in many cases a shift in peak-load demands and the time of day of the peak load.
Ambient or interior temperature cycling past the phase change temperature range is necessary for the PCM to function. The design of a PCM application requires selection of material, identification of PCM location and bounding thermal resistances, and specification of the amount of PCM to be used. PCM can be distributed in an insulation or building material or packaged for localized application. This paper describes small-scale laboratory testing, large- scale laboratory testing, and field studies undertaken to evaluate the energy savings potential for PCM in the building envelope.