Polymer encapsulated nano phase change materials (paraffin) in particulate form (nano PCM) are added in water to enhance the heat transfer performance of jet impingement and spray cooling. The nano PCM particles absorb heat when paraffin changes from solid to liquid phase. The encapsulation prevents paraffin leakage and agglomeration. The volume fraction of nanoparticles plays an important role on pressure drop and heat transfer. Slurry with 28% particle volume fraction enhances heat transfer coefficient by 50% and 70% when compared to base solution for jet impingement and spray cooling, respectively. The structural integrity of shell encapsulation has been demonstrated by repeated use in a closed loop.