Solar PV installations come with a stack of overlapping warranties that protect different system elements over different time horizons. Understanding what each warranty covers — and how to claim against it — protects your investment over the 25+ year system life. Here's the 2026 picture for UK farm installations.
The four warranty layers
**Panel manufacturer warranty.** Two components: product warranty (covers manufacturing defects) typically 12-25 years; performance warranty (guarantees output stays above a stated percentage of rated output) typically 25-30 years. Top brands: LONGi (15-yr product, 30-yr performance at 84.8%); JA Solar (12-yr product, 30-yr performance at 84.8%); REC (25-yr product, 25-yr performance at 92%); Q-Cells (12-yr product, 30-yr performance). The product warranty pays for replacement panels; the performance warranty pays compensation if the panels underperform their guaranteed output curve.
**Inverter manufacturer warranty.** Typically 10 years standard, extendable to 20-25 years through manufacturer programmes. SolarEdge extends to 25 years via registration; SMA, Huawei, Fronius offer 5-10 year extensions through paid programmes. Inverter warranty pays for replacement units; some manufacturers also cover labour for swap (others pay parts only).
**Installer workmanship warranty.** Covers the installer's work — connections, fixings, cabling, racking installation, system design. Typically 10 years for reputable installers. Pays for repair/replacement of faulty workmanship and any consequential damage during the warranty period.
**IWA insurance-backed warranty.** The critical fourth layer — provides 10 years of workmanship cover that pays out even if the original installer goes out of business. Without IWA backing, your workmanship warranty is worthless the day the installer becomes insolvent. We register every install with IWA as standard.
What's typically not covered
Fair-wear-and-tear (panel cleaning, inverter air-filter replacement, vegetation management around the array); damage from external events (lightning, storm damage, vandalism — these go through your insurer); modifications by other contractors (any third-party work that wasn't part of the original install scope); incorrect operation (running the system outside specified operating limits — rare, but possible).
How to claim — the practical process
Step 1: notice the fault. This is where active monitoring is critical — the portal raises an alarm; we (or your monitoring contractor) confirm the fault diagnosis.
Step 2: classify the fault by warranty layer. Panel defect → manufacturer warranty. Inverter failure → manufacturer warranty. Cable/fixing/connection failure → workmanship warranty (and IWA insurance backstop). Storm damage → buildings/contents insurer.
Step 3: lodge the claim with the appropriate party. For panels and inverters, we lodge directly with the manufacturer on your behalf — this is the standard service we provide. For workmanship, we attend site and repair/replace under our own warranty. For IWA-backed claims (if we're insolvent), IWA can be contacted directly using the policy reference in your handover pack.
Step 4: resolution. Manufacturer warranty claims typically resolve within 4-12 weeks (depending on shipping and lab testing for failed panels). Workmanship claims resolve within 1-4 weeks. IWA claims (rare) resolve within 6-12 weeks.
Cost coverage during claim
During the warranty period: parts covered by the relevant warranty (manufacturer or workmanship). Labour for swap-out: typically covered by manufacturer programmes for inverters; varies for panels (some manufacturers cover, some require farm to pay labour). For workmanship claims during our 10-year warranty: parts and labour both covered.
During the IWA backstop period (years 1-10 after installer insolvency): IWA covers up to £25,000 per claim and up to £100,000 lifetime per site. Excludes consequential losses (lost generation revenue while system is offline).
What to keep for warranty claims
The handover pack we provide at commissioning contains: panel and inverter serial numbers; manufacturer warranty registrations; IWA policy reference; installer details and contact information; complete electrical drawings; MCS commercial certificate. Keep this pack accessible for the system life. We retain digital copies indefinitely.
Insurance considerations
Beyond warranty: every farm should ensure the PV system is covered under buildings insurance. Most NFU Mutual and Aviva farm policies include PV up to a notification threshold (typically £100,000-£250,000); above this, declare the system explicitly. Premium impact is minimal — typically 1-3% of the system value annually. Don't proceed without confirming insurance position.
Long-term warranty trajectory
Years 1-10: full warranty stack active. Years 10-12: workmanship warranty expires; IWA backstop expires; panel and inverter warranties continue. Years 12-15: typical first inverter replacement (out of warranty unless extended). Years 15-25: panel performance warranty continues; system in mature operational phase. Year 25-30: end-of-life decisions — re-power with new modules, complete refurbishment, or decommission. We assist clients with re-powering analysis as the original system approaches year 25.
Practical recommendations
For every farm solar install: ensure full four-warranty stack at commissioning; register all manufacturer warranties at installation; keep the handover pack accessible; declare the system to your insurer; sign up to manufacturer warranty-extension programmes where cost-effective; use active monitoring to detect faults early (before they become harder/more expensive to fix); choose installers who carry IWA backing (avoid those without).