Why Solar PV Maintenance Matters for UK Homes

Solar PV systems are highly reliable, but like any electrical installation, they require ongoing maintenance to remain safe, efficient, and compliant. In the UK, the importance of solar panel maintenance is growing rapidly as deployment increases and incident data highlights the risks of neglect.

Maintaining Energy Yield

The single biggest performance issue after sunlight availability is soiling — the gradual build-up of dust, pollen, bird fouling, or traffic pollution on panel surfaces.

• An international review estimated soiling reduced global PV output by 3–4% in 2018, rising towards 5% by 2023 (IEA-PVPS).

• In the UK, the effect varies with location. Homes near trees, farmland, or high-traffic routes typically see higher losses.

Routine cleaning and seasonal inspections (spring and autumn) can prevent avoidable yield loss and maximise return on investment.

Identifying and Preventing Safety Issues

Most technical failures begin as minor defects:

• loose connectors

• cracked tiles

• water ingress

• deteriorated cabling

• incorrectly set inverter parameters

If left unchecked, these issues can escalate into hotspots, nuisance trips, or—on rare occasions—fires.

📊 Key data points:

• A BRE/BEIS review logged 80 PV fire incidents in the UK, with ~30% linked to DC isolator failures.

• UK fire safety bodies report a six-fold increase in PV-related fires over the past decade.

Regular visual inspections and electrical testing identify faults before they become critical, helping homeowners avoid costly repairs and serious safety risks.

Compliance with UK Standards and Insurer Expectations

PV maintenance in the UK is not just good practice; it aligns with legal, technical, and insurance requirements:

• Legal: The Electricity at Work Regulations 1989 require dutyholders to control electrical risks, including through inspection and maintenance.

• Standards: IEC/BS EN 62446-1/2 set requirements for preventive and corrective maintenance, including verification tests and documentation.

• Insurance: The Fire Protection Association’s RC62 guidance outlines PV-specific risk control measures widely used by insurers.

• Professional frameworks: The IET Code of Practice for Grid-Connected PV and MCS MIS 3002 require handover and inspection documentation, supporting long-term system safety.

Adhering to these standards not only enhances safety but also protects warranties and ensures insurers recognise that systems are being responsibly maintained.

What “Good” PV Maintenance Looks Like

A professional solar PV maintenance visit should include:

• Electrical testing (per IEC 62446-1): polarity, insulation resistance, IV curves, thermal scans.

• Visual inspections: modules, frames, mounting systems, fixings, isolators, connectors, labels, and cable routes.

• Inverter and battery checks: firmware, export limits, and optimisation of settings.

• Panel cleaning: using deionised water and soft brushes (avoiding pressure washing).

• Reporting: a documented record of findings, photos, remedial recommendations, and inspection intervals.

If an O&M manual is missing, maintainers should re-establish it (system data, drawings, test records, inspection schedules). Proper records support warranty claims and provide assurance for insurers.

How Often Should PV Systems Be Maintained?

• Annually: Visual inspection, electrical verification, and panel cleaning.

• Every 6 months: In high-soiling areas (e.g. farms, coastal locations, heavy traffic zones).

• Immediately: If monitoring shows underperformance, or if there are visible defects, water ingress, or repeated inverter alarms.

Treat PV systems as you would any other electrical asset: planned inspection and maintenance protect performance, reduce risks, and extend system life.

Conclusion

With over 190,000 MCS-certified installations added in 2023, more UK homes than ever rely on solar PV. But as adoption grows, so does the responsibility to maintain these systems.

The data is clear:

• Soiling reduces efficiency.

• Minor faults escalate into costly failures.

• Fire risks, while rare, are increasing.

Regular, standards-based maintenance keeps systems safe, compliant, and efficient—ensuring your solar investment pays back for decades.