Solar panels and Perth weather: hail, storms, and high winds

Perth's climate is one of the best in Australia for solar generation — high sunshine hours, low humidity, and minimal extended cloud cover. But Perth also experiences summer thunderstorms, East Coast-style cold front systems in winter, and periodic severe weather events. Here's a realistic guide to how solar systems perform in Perth weather and what to do if an event causes damage.

Perth's typical weather hazards for solar

Summer thunderstorms (December–March): Perth experiences afternoon thunderstorms during summer, more frequently in the Perth Hills but occasionally reaching the coastal plain. These can bring hail, lightning, and gusty winds. The storms are typically shorter-lived than east coast convective events but can be intense.

Winter cold fronts (May–August): Perth's dominant severe weather pattern. Southern Ocean cold fronts bring heavy rain, gale-force winds (70–100km/h gusts are common), and occasionally large hail. The State Emergency Service (SES) Perth sub-centre responds to hundreds of storm damage calls during major fronts.

Coastal afternoon sea breeze: The Fremantle Doctor (afternoon sea breeze from the south-west) is a daily Perth summer occurrence. While typically pleasant, peak gusts during the onset (3–4pm) can reach 35–40km/h, and in summer storm conditions, significantly higher.

What standard solar panels can withstand

Solar panels sold in Australia must meet IEC 61215 performance and safety requirements. Part of this standard includes hail impact testing:

• Hail impact test (IEC 61215 standard): 25mm diameter hailstones at 23 m/s (83 km/h) from multiple angles
• This represents severe but not extreme hail — residential hailstorms in Perth rarely produce hailstones larger than 25–30mm

Wind load ratings: IEC 61215 requires panels to withstand static load of 2400 Pa (roughly 220 km/h equivalent wind pressure) in standard testing. Perth's wind loading zones (AS/NZS 1170.2) classify most of metropolitan Perth as Region B/C — standard engineering territory. Coastal suburbs have higher wind exposures classified under Region C.

A panel installed to Perth's required mounting standards should withstand normal winter storm conditions. Damage from hail within normal seasonal parameters typically indicates either an unusually severe event or a pre-existing defect.

Hail damage: what to look for

After a significant hail event, visually inspect the panels from ground level or (carefully) from inside the roof if accessible:

Signs of direct hail impact:

• Spiderweb cracks in the tempered glass (visible as radial fractures)
• Shattered glass (rare — tempered glass resists penetration but can crack from a direct strike)
• Dimpling of the frame at impact points

Signs of a damaged panel without obvious glass damage:

• Hot spots visible in thermal imaging (requires specialised equipment)
• Significant drop in output in your monitoring app immediately after the storm

What to do:

• If no visible damage and output is normal: the system is likely fine
• If you see cracked glass: stop using the system (isolate at the AC isolator on the switchboard) and call your installer immediately. Cracked solar panel glass can allow water ingress and represents a safety risk.

Wind damage: mounting and racking

Solar panel mounting systems are the most vulnerable component in high-wind events, not the panels themselves. Perth-installed solar must meet the structural requirements of AS/NZS 1170.2 for the local wind region, which determines fastener spacing, clamp load ratings, and rail specifications.

Signs of wind damage:

• Panels visibly shifted or tilted after a storm
• Racking rails lifted or bent
• Tile hooks or Colorbond clamps pulled from the roof

If panels have shifted, stop the system at the AC isolator and call your installer. A shifted panel may have damaged DC cabling — operating the system with damaged cables is a fire and electrocution risk.

After any storm: Check the monitoring app the following morning. A complete system offline event that coincides with a storm may indicate storm-related damage or a simple tripped circuit breaker. Check the AC isolator and circuit breaker for the solar circuit before assuming inverter damage.

Lightning: inverters and surge protection

Lightning is rare in Perth compared to the tropical north, but summer thunderstorms can bring lightning. Solar inverters contain sensitive electronics that can be damaged by a nearby lightning strike via the power grid, even without a direct strike on the system.

Surge protection devices (SPDs): Quality inverter installations include AC-side and DC-side surge protection devices. Ask your installer what surge protection is included in their proposal. An SPD on the DC side (between panels and inverter) and AC side (at the inverter output) provides protection against surge damage from nearby lightning.

If your inverter shows faults after a storm: Check fault codes in the monitoring app. "Grid fault" codes immediately after a storm typically indicate the inverter disconnected due to grid disturbance (normal, reconnects after 5 minutes). Persistent faults or inverter failure to restart may indicate surge damage — call your installer.

Home insurance and storm damage

Most Perth home and contents insurance policies cover storm damage to solar systems under the building sum insured, provided:

• The system is installed by a licensed contractor (a CEC-accredited installer meets this requirement)
• You notified your insurer when the system was installed (failure to notify can be grounds for a claim dispute)
• The damage is caused by a storm event (not general wear or manufacturing defect)

When making a storm claim:

1. Document the damage with photos before any temporary repairs
2. Call the SES (13 25 00) if the damage is causing an immediate safety hazard
3. Contact your insurer promptly — most policies require prompt notification
4. Keep your original installation documents (installer's certificate, NCN approval) — insurers may request them

What's typically not covered: Cosmetic damage that doesn't affect performance (small frame dents, minor glass surface marks), manufacturing defects discovered during a storm inspection, or pre-existing damage that wasn't reported.

After the storm: first checks

1. Visual inspection from ground level: visible glass damage, shifted panels, loose mounting
2. Check AC isolator: Is it still in the ON position? A tripped breaker is common after a grid disturbance.
3. Check monitoring app the next morning: Normal generation = no functional damage
4. If any doubt: Call your installer for a professional post-storm inspection

Perth solar systems are built to survive standard winter storms and summer hail events. After a significant weather event, check the monitoring app for output and visually inspect for glass damage or shifted panels. If you see cracked glass or shifted panels, isolate the system at the AC isolator and call your installer — don't wait for the next scheduled visit.