How to Protect Solar Panels Against Lightning, Wind and Corrosion

Solar PV systems are exposed to the outdoors for long periods. Lightning protection, wind resistance and corrosion resistance directly determine safety, service life and power generation income. This article provides practical solutions based on industry standards and engineering best practices.

1. Lightning Protection: Defend Against Direct and Induced Lightning

PV arrays in open areas are highly vulnerable to lightning. A three-level protection system is applied: external direct lightning protection + internal surge protection + equipotential grounding, in accordance with QX/T 263 and GB/T 36963.

• Direct lightning protection: Metal frames of PV modules can act as air terminals. Lightning rods or strips are installed around the array without shading. Down conductors use hot-dip galvanized flat steel or copper          cables.

• Grounding and equipotential bonding: Combined grounding resistance ≤ 4Ω. All supports, frames, cables and equipment enclosures are connected equipotentially to eliminate potential differences.

• Surge protection: SPDs are installed on DC and AC sides of combiner boxes, inverters and grid connection points.

• Maintenance: Test grounding resistance and check SPD status after thunderstorms.

2. Wind Resistance: Stable Structure and Reinforced Installation

Designed according to local 50-year return wind speed (GB 50009), focusing on preventing uplift, overturning and fatigue failure.

• Supports and foundations: Ground systems use screw piles or concrete foundations; flat roofs use ballasts; pitched roofs use structural hooks.

• Materials and structure: Q355B steel, 6061‑T6 aluminum alloy with qualified wall thickness. Tracking systems are equipped with typhoon return and shutdown functions.

• Installation: Modules are firmly fixed with clamps; lock nuts and washers are used in high-wind areas.

3. Corrosion Protection: Material Selection and Coating Protection

Designed for C4‑C5 high-corrosion environments (GB 50797), extending service life to 25 years.

• Support corrosion protection: Hot-dip galvanizing for carbon steel; zinc‑aluminum‑magnesium coating for coastal areas.

• Fasteners: 304 stainless steel for normal environments, 316L for coastal/salt fog areas.

• Special environments: Sacrificial anodes for offshore PV; drainage and isolation for saline‑alkali areas.

• Maintenance: Regularly inspect coating damage, rust and loose fasteners.

4. Integrated Design and Maintenance Checklist

• Design: Calculate wind load, corrosion zone and lightning protection level based on region.

• Construction: Complete on-site corrosion repair; ensure qualified grounding and torque.

• Operation: Quarterly inspection; half-yearly grounding test; special inspection after typhoons.

Conclusion

Lightning protection ensures safety, wind resistance stabilizes the structure, and corrosion protection extends service life. Combined with standard design, construction and maintenance, the PV system can operate stably and reliably with high benefits over its lifetime.