Four different paraffin-based nanocomposite phase change materials (PCMs) were prepared by dispersion of 20 v. % of graphene, multi-walled carbon nanotubes (MWCNTs), aluminum, or TiO2 nanoparticles into a paraffin matrix. It was found that the two carbon-based nanoparticles reduced the time required for melting and solidification of the PCM by a greater amount than the two other nanoparticles. The graphene-paraffin PCM was found to reduce the melt and re-solidification time by the ...