What happens to solar panels during a lightning strike
A lightning strike can send a sudden surge through a rooftop photovoltaic system, but the glass module is rarely the first component to fail. Current often reaches wiring, earthing, switchgear or the grid connection, where protective devices and sensitive inverter electronics determine the outcome.
Many Australian homes in Sydney, Melbourne, Brisbane and Perth carry rooftop solar. Summer thunderstorms, metal or tile roofs, nearby trees and long cable routes make lightning protection a practical concern. A well-designed system usually contains the event, although no installation is immune to a direct hit.
The result depends on where the lightning current travels and how quickly it is diverted. Visible damage may include a scorched connector or cracked glass, while a subtler failure can appear as an inverter fault, safety trip or sudden loss of generation.
This guide explains how a strike affects panels and connected equipment, what owners can safely check after a storm, and which protection measures suit Australian conditions. It avoids advice that would require handling high-voltage equipment or climbing onto a wet roof.
How lightning reaches a solar array
Lightning does not have to strike a panel directly. A close strike can send current through a tree, mast, roof edge or service line and produce a side flash into the array. It can also induce a voltage spike in nearby wiring without making physical contact.
Ground current raises the voltage of buried or metal services, while a distant cloud-to-ground event creates an electromagnetic surge. The array may therefore see a brief voltage spike at its DC inputs, on the AC output or through communications cables.
On a typical installation, current follows engineered paths: module strings, junction boxes, isolation switches, protective devices, earthing conductors and the property’s main switchboard. The weakest link, rather than the strongest sunlight or the panel surface, often determines the damage.
Damage that can occur across the system
Module damage may include cracked cells, a failed bypass diode, heat damage to a junction box, melted connectors or degraded insulation. Individual cells can be bypassed, but a series string may stop producing if its protective diodes or connections fail. Water can then reach conductors.
The inverter is usually more vulnerable to a large surge than the laminated cells. Its printed circuit boards, relays, communications interface and grid connection can be damaged, causing no output, constant resetting or an insulation alarm. A protective device may disconnect the system correctly, even when no component has burned.
A powerful event may also damage roof-mounted equipment, antennae, cabling or the main switchboard, and it can leave moisture around the array. Fire is uncommon, but charred insulation, arcing or a hot cable requires isolation by a qualified electrician and, where necessary, emergency services.
Safe checks after a storm
After a close strike, keep people away from the array, damaged cables, metal roof structures and any wet area. Do not touch wiring or attempt to retrieve a loose module. If smoke, fire or arcing is visible, call 000 and remain clear until the site is safe.
From the ground, check the inverter display or monitoring app and note any error code, abnormal indicator or unexplained loss of production. A normal protective trip may reset once the cause is gone; repeated resets, burnt smells, visible damage or persistent faults need an electrician rather than further toggling.
Remember that disconnected modules can still generate lethal DC voltage whenever light reaches the cells. Do not climb onto the roof or open a combiner box. Switch off a visibly damaged system only if you can do so from a normal, accessible control point; otherwise leave it isolated and call a qualified solar electrician.
Australian conditions and installation rules
Lightning risk varies across Australia. Darwin and Cairns experience intense tropical thunderstorms, while the humid east coast around Brisbane and Sydney, and widespread storms across Victoria, Melbourne and inland New South Wales, can produce damaging seasonal events. Tree proximity and roof design matter as much as the city postcode.
Installations should follow AS/NZS 5030 for solar arrays, AS/NZS 3000 for electrical wiring and the relevant state Electricity Safety legislation, including NSW’s Electricity Safety Act 2023 or Victoria’s Electricity Safety (General) Regulations 2022. Grid-connected inverter settings are also governed by AS/NZS 4777 series requirements and the network operator’s rules.
Australia’s large rooftop market now includes string inverters, microinverters and battery systems, often paired with apps and utility-controlled relays. A licensed electrician should coordinate surge protection, earthing and switching with the retailer, distribution network service provider and manufacturer instructions, because each device has a different isolation role.
Protection measures that reduce the risk
Lightning protection is a coordinated design, not simply a metal rod on the roof. Where a risk assessment justifies it, an air terminal, down conductor and correctly engineered earth electrode can intercept a strike and carry current safely into the ground under AS/NZS 1760.
Surge protective devices provide another layer at the DC, AC or communication entry points. Equipotential bonding reduces voltage differences between metalwork, correctly sized overcurrent protection isolates faults, and short, suitable cable routes limit surge strength. Many modern SMA inverters also provide monitoring and controlled grid-protection functions, but their safety depends on the surrounding installation.
No surge device absorbs unlimited energy, and a failed protector can leave the system exposed. Replacement parts should match the inverter and array design, and damaged modules should be handled through a reputable recycling pathway. When premature replacement is unavoidable, consider the solar manufacturing environmental impact alongside safety and lifecycle cost.
Comparing likely outcomes after a lightning event
The same storm can produce very different outcomes. The deciding factors are the strike path, distance, earthing quality, protective coordination and whether a damaged component was isolated before more energy entered the system.
| Event | Usual result | What to look for | Appropriate response |
|---|---|---|---|
| Distant strike or induced surge | Protective devices may disconnect briefly; inverter returns to normal | Intermittent grid error, brief shutdown | Record the event and monitor; investigate repeated trips |
| Close side flash | Current can enter the roof, array or service conductors | Tripped breakers, scorch marks, damaged cabling | Keep clear and arrange a licensed electrician’s inspection |
| Direct strike or severe ground event | Multiple electrical components can fail together | Burning smell, arcing, broken glass, persistent fault | Isolate safely, call 000 for fire or arcing, and seek urgent electrical assessment |
A protective trip is therefore not proof that damage occurred, and an undamaged-looking panel is not proof that the system is safe. Compare the inverter state, metering data, breaker labels and physical observations before deciding whether a simple reset is reasonable or a full inspection is needed.
Storm-ready checks for Australian solar owners
Two short checklists can help owners prepare for severe weather and respond consistently afterwards:
- Have a licensed electrician verify earthing, equipotential bonding, surge protective devices, cable routing and isolation points before storm season.
- Trim vegetation only within safe distances and with suitable equipment; never approach trees or metal structures during a storm.
- Confirm the inverter app, emergency shut-off and monitoring contacts work, and keep the system’s serial number and installer details handy.
- Review household insurance and temporary arrangements for essential medical equipment or refrigeration.
Following a nearby strike, use this sequence:
- Stay clear of the roof, wiring, water and any damaged component, and call 000 for smoke or fire.
- Check the inverter and energy monitor from a safe, dry location, then record the displayed fault and the time.
- Avoid repeated resets if there is burning, arcing, water intrusion or a persistent insulation or isolation error.
- Arrange an inspection by a qualified solar electrician and provide the event date, system model and photographs from ground level.
Take action before the next storm: contact a licensed solar electrician for a protection review, or use the Andre C Week resource hub to gather installation guidance. Record the findings, correct any failed protective device, and keep the final report with the system’s warranty and insurance documents.