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The key technical points of lightning protection for solar water heaters are presented through the theoretical analysis of lightning disasters and the related researches on various lightning protection standards from the following three aspects: the protection of direct lightning strokes for solar collectors, the LEMP (Lightning electromagnetic impulse) protection of electric and automatic control systems, and the protection of user’s personal safety. It is suggested that the risk of lightning damage should be estimated according to the heights of the buildings on which solar water heaters are installed and the annual mean numbers of lightning days in the related areas to decide whether it is necessary to install a lightning arrester around the collector. For the LEMP protection of electric and automatic control systems, the oneoff investment and the ratio of maintenance fee to equipment cost should be considered in determining whether such measures is necessary as shielding, equipotential bonding, flashover protection (rational wiring), and SPD (Surge Protective Device) installation.