Complaints: What Goes Wrong

What are the most common solar panel complaints?

UK solar panel complaints — categorised from MCS, RECC, and consumer review data: CATEGORY 1 — INSTALLER COMMUNICATION (30%): Slow response to queries. Missed installation dates. Poor explanation of system operation. FIX: Choose installers with 4.5+ Trustpilot rating and recent reviews. CATEGORY 2 — OUTPUT BELOW EXPECTATIONS (25%): Actual generation lower than quoted estimate. Often caused by: shading not properly assessed, orientation overestimated, or unrealistic self-consumption assumptions. FIX: Demand PVGIS-based estimates. Ask what self-consumption rate they're using. CATEGORY 3 — POST-SALE SUPPORT (20%): Difficulty reaching installer for warranty issues. Some companies dissolved. FIX: Choose established companies (5+ years trading). Check Companies House for financial health. CATEGORY 4 — HARDWARE FAULTS (15%): Inverter failures (most common). Panel defects (rare). Mounting issues (very rare). FIX: Choose tier-1 panels and reputable inverters with 10+ year warranties. CATEGORY 5 — ADMINISTRATIVE (10%): DNO notification delays. MCS certificate not received. SEG registration issues. FIX: Confirm timeline for all paperwork in your contract. COMPLAINT RATE: approximately 3-5% of installations result in a formal complaint. 95%+ are resolved within 6 months. Sources: MCS complaints data (mcscertified.com), RECC (recc.org.uk), Citizens Advice.