Considerations about the lightning protection system of mains independent renewable energy hybrid-systems—practical experiences

In the paper, a lightning protection design concept for a renewable energy hybrid-system without power mains connection, VATALI on the Greek island Crete, is described. Based on the risk analysis protection measures against direct strikes and overvoltages are defined. VATALI, not lightning protected at that time, was a victim of a lightning strike in the year 2000 causing destructions and damages of some mechanical and electrical components with costs of approx. €60,000. The hardware costs for the protection measures were about €15,000: about 50% of the costs are due to protection measures against direct strikes, 50% are due to overvoltage protection.