Solar Panel Installation
MCS-certified domestic install, 3-6kW typical. 0% VAT through March 2027. Tier 1 panels, hybrid inverter, SEG setup.
From £4,500Solar system not generating? Inverter warning lights? Output dropping? Get matched with a vetted Cornwall solar repair specialist — full fault diagnosis, then transparent quote before any work.
Solar PV systems are reliable but not bulletproof. Inverters typically fail first — they're the only major component with active electronics, and a 10-12 year service life is normal. Panels themselves usually last 25-30 years, but individual cells can fail (hot spots, micro-cracks, delamination) and the diode connectors in junction boxes can degrade. Isolators, DC cabling and AC switchgear all have finite lives too.
Common solar faults we diagnose in Cornwall:
Diagnosis first, then quote. A proper fault-find visit is £80-£150 in Cornwall, and includes electrical testing (Megger insulation test, DC voltage check, AC output check), inverter error-log download, and a written report. From there, repair costs depend on what's failed:
Typical Cornwall repair costs (at time of writing):
All repair specialists in our network work to BS 7671:2018+A2:2022 Section 712 (Solar PV electrical installations) and are MCS-aware. If your install is still under MCS workmanship warranty, we'll route to a compatible MCS-certified installer to preserve the warranty chain.
Getting a Cornwall MCS-certified solar panel repair specialist shouldn't be a fortnight of cold calls. Here's how it works.
Fill in the quick quote form. Tell us your Cornwall postcode, property type, the job (new install, battery, clean, repair, commercial, farm or holiday let) and rough timing.
We pair you with a vetted Cornwall MCS-certified, RECC-registered solar panel repair specialist near you. Site survey arranged direct — usually within 1-2 weeks, faster for repairs.
Survey, written quote, G98 or G99 DNO application, scaffolding, install, commissioning, MCS certification and Smart Export Guarantee paperwork — all handled by your matched installer.
Need something other than solar panel repair? We cover the full range of Cornwall solar work — domestic, commercial, farm, holiday let, batteries, cleaning and repair.
MCS-certified domestic install, 3-6kW typical. 0% VAT through March 2027. Tier 1 panels, hybrid inverter, SEG setup.
From £4,500Tesla Powerwall 3 (13.5kWh), GivEnergy 5.2-13kWh, Enphase IQ Battery. Hybrid or AC-coupled retrofit.
From £5,500Coastal grime, bird droppings, lichen reduce yield by 5-15%. Pure-water reach systems, annual clean recommended.
From £75/visitInverter replacement (10-12 yr lifespan typical), microinverter swaps, DC isolator failures, full fault diagnosis.
From £150 diagnosticHotels, holiday let portfolios, offices, retail, warehouses. 5-8 year ROI typical with G99 grid connection.
Bespoke quoteAgricultural roof and ground-mount installs. AIA-eligible plant and machinery. Diversification income.
Bespoke quoteOffset guest electricity, EV-charger integration, SEG export income on summer-peak generation.
From £4,500Indicative installed prices for typical 2026 Cornwall jobs. Your matched MCS-certified installer gives a firm written quote after survey.
Entry-level MCS-certified PV install — 7-9 Tier 1 panels, string inverter, SEG setup. 0% VAT to March 2027.
Most common 2026 spec — 10-12 panels, hybrid inverter, GivEnergy or equivalent battery. 0% VAT on full package.
13.5kWh Powerwall 3 fitted to existing PV — AC-coupled or hybrid inverter swap. App control, full home backup option.
Commercial roofs, holiday parks, farms. G99 DNO application included. AIA tax relief and 5-8 year ROI typical.
We cover the whole of Cornwall — find your nearest town to connect with a vetted local MCS-certified solar installer in your area.
Everything you need to know about solar panel repair in Cornwall.
8-12 years is typical for the inverter — it's the most likely component to fail first. Panels themselves last 25-30 years (with gradual output degradation, usually ~0.5% per year). When your inverter goes, the panels are still good — you replace the inverter, not the whole system. Budget for one inverter replacement over the lifetime of the panels.
£1,500-£2,800 installed for a typical 4-6kW hybrid inverter (Solis, GivEnergy, SolarEdge, Fronius). Add £500-£1,500 if you're upgrading to a battery-ready hybrid model that wasn't there before. Microinverter systems (Enphase) are different — individual unit replacement at £150-£300 each. Always get the diagnosis first to confirm it's the inverter, not a panel or isolator fault.
Most common causes: dirty panels (bird droppings, lichen, salt — 10-25% drop possible), inverter underperforming or failing, DC isolator corrosion (very common coastal Cornwall), string fault (one panel or connector failed, taking the whole string offline), shading changes (new tree growth, neighbouring structure). A diagnostic visit will tell you which.
Yes. The MCS workmanship warranty transfers to the MCS Installer Insurance scheme (formerly RECC IWA) if the original installer ceases trading — provided the install was registered with MCS at the time. For out-of-warranty work, any MCS-aware repairer can take it on. Bring the original MCS certificate if you have it; we'll route accordingly.
Sometimes. Storm damage, lightning strike and accidental damage may be covered under your home insurance (check the policy). Wear-and-tear failures (inverter end-of-life, isolator corrosion) usually aren't. MCS workmanship warranty covers installation defects for 2-10 years depending on the scheme; component warranties (panel, inverter) are separate and run 10-25 years.
Yes — it's the single most common solar fault in coastal Cornwall. Older isolator boxes (pre-2018 in some cases) had poor ingress protection; salt-laden air corrodes contacts and rain ingress trips the system. Replacement is £150-£300 and should be done as a priority — failed isolators can arc and in worst cases cause fires. New units are IP65-rated minimum.