ITU-T Recommendation K.105 provides the lightning protection procedures for protecting dedicated photovoltaic power supply systems used to provide electric power for radio base stations. This Recommendation describes the bonding and earthing procedures applied to the metallic supports of the photovoltaic array, considering the following scenarios for the installation of the photovoltaic array: on the ground surface, on the rooftop, and on the tower. For each scenario, it is considered the possibility of installing the electronic controller either close to the photovoltaic array or close to the DC load. This Recommendation also provides the configuration and rating of protection modules required to protect the electronic controller and the photovoltaic array against lightning surges.