Greece – Lightning Overvoltage Protection for Weak Island Grids

Project Background

Greece has over 3,000 islands, many powered by weak island grids – low short-circuit capacity, low inertia, and high sensitivity to voltage fluctuations. The Aegean Sea region experiences frequent summer lightning storms, causing:

• Repeated lightning trips on overhead lines
• Arrester failures and transformer burnouts
• High outage costs during peak tourist seasons

An island distribution utility urgently needed a 15-36kV overvoltage protection solution tailored for weak grid + high lightning exposure.

Fuerte Solution

Zhejiang Fuerte provided an integrated island grid protection package:

1. High-Energy Distribution-Class Arresters (YHSeries)

• Fast response MOA varistors per IEC 60099-4
• High energy absorption capability for multiple successive lightning strikes
• Composite housing for salt-fog and humidity resistance

2. Fully Insulated Drop-out Fuses

• Enclosed structure prevents oxidation and moisture ingress in seaside environments
• Prevents nuisance tripping caused by salt contamination

3. Customized Insulation Coordination

• Recalculated protection parameters based on actual island short-circuit capacity and insulation levels
• Achieved optimal coordination between arresters, fuses, and transformers – no protection dead zones

4. Full Technical Support

• Pre-sales insulation coordination and protection grading study
• On-site installation and commissioning support

Project Results & Customer Feedback

After the 2024 lightning season, the utility reported:

• 55% year-on-year reductionin line trip-outs due to lightning
• Zero transformer burnouts– eliminated by proper arrester-fuse coordination

“We had tried several suppliers, but the problems never went away. Fuerte’s team took time to understand our weak grid characteristics. Their solution finally fixed the problem. Good price, fast delivery, and real engineering capability.”
— Technical Director, Greek Island Distribution Utility