Table 1.

Main features of the different class of PCMs.

Type of PCM	Composition	Melting Temperature (°C)	Heat of Fusion (J/kg K)	Cost
Organic	Paraffin	−12–71	190–260	Costly
	Non-Paraffin	8–187	130–250	Highly costly
Inorganic	Salt hydrates	11–120	100–200	Low Cost
	Metallic	30–96	25–90	Costly
Eutectic	Paraffin	4–93	100–230	Costly
	Non-Paraffin	−12–71	190–260	Costly