Erratum to: Numerical modelling of phase-change material used for PV panels cooling Assia Sellami, Rabie Elotmani, Khalid Kandoussi, Mohamed Eljouad, Abdelowahed Hajjaji and M’Hamed Boutaous Eur. Phys. J. Plus, 133 7 (2018) 255 Published online: 10 July 2018 DOI: 10.1140/epjp/i2018-12115-x