Microencapsulated phase change materials may be used in a powder form or dispersed into a carrier fluid, e.g. water, to significantly enhance heat transfer efficiency of the carrier fluid. This kind of suspension was named as microencapsulated phase change material slurry (MPCS) [14] and [15]. The addition of nano-particles to MPCS was suggested by Zhang et al. [16] to improve the thermal conductivity of MPCS. However, the major limitations of the MPCS contained nano-particle are the instability and agglomeration of nano-particles and MEPCMs in carrier nano-fluid.