36. Maintenance, Repair & Repower
Learning objectives
- Plan preventive and corrective maintenance over the asset’s life.
- Handle component replacement, repowering, and end-of-life.
36.1 Preventive maintenance
Scheduled care: visual inspection, cleaning where soiling is significant (often rain-sufficient, but not in dusty/low-rain areas), connector and torque checks, periodic insulation/thermal scans, and vegetation/shading control. Documentation maintains warranty validity.
36.2 Corrective maintenance and repower
- Inverters are the most-replaced component, typically wearing out at ~10–15 years versus the modules’ 25–30. Plan for at least one inverter replacement in the system’s life.
- Modules are swapped individually for failures; ⚠️ matching an old module’s electrical characteristics gets hard as products change (mismatch, Ch 5.2).
- Batteries have their own maintenance and end-of-life replacement.
- Repowering upgrades aging arrays (often inverter or module-level) to restore or boost output.
- End-of-life: modules and batteries enter growing recycling streams; responsible decommissioning is an emerging professional expectation (Ch 45).
36.3 A maintenance schedule at a glance
| Interval | Task |
|---|---|
| Continuous | Remote monitoring; alert review; PR tracking (Ch 34) |
| Annual / semi-annual | Visual inspection; cleaning (if soiling-prone); vegetation/shade control |
| Periodic | Connector & torque checks; insulation & thermal scans |
| ~10–15 yr | Inverter replacement (the expected wear-out item) |
| As needed | Module swap (mismatch care); battery service/replacement; repower |
| End-of-life | Decommission; module/battery recycling |
Chapter 36 summary
Maintain preventively (inspect, clean, check connectors/torque, scan, manage shade) to protect output and warranties. Expect to replace the inverter at ~10–15 years, swap modules with mismatch care, maintain batteries, repower aging arrays, and recycle at end-of-life.
- Preventive maintenance: scheduled inspections, cleaning, connector/torque checks, and thermal scans that protect output and warranty validity.
- Corrective maintenance: reactive work to diagnose and fix failures, including component replacement.
- Repowering: upgrading an aging array (inverter or module level) to restore or increase output.
- Mismatch: output loss caused by pairing modules with different electrical characteristics.
- End-of-life / recycling: responsible decommissioning of modules and batteries into established recycling streams.
Full definitions: Appendix A (glossary).
Practice Problems: Chapter 36
- Which component should you expect to replace during a system’s life, and roughly when?
- Why is swapping a single failed module harder years later than at install?
- In many climates, what natural process handles much of the soiling, and where does that assumption break down?
- What does “repowering” mean?
- Why does keeping maintenance records matter beyond good practice?
Solutions: Chapter 36
- The inverter, at roughly 10–15 years (vs 25–30 for modules).
- Module products change; matching the electrical characteristics of a discontinued module is difficult, risking mismatch losses.
- Rainfall cleans panels in many areas; the assumption breaks down in dusty, low-rain, or high-pollution climates where manual cleaning is needed.
- Upgrading an aging array (often inverter- or module-level) to restore or increase output.
- Records maintain warranty validity and document the asset’s condition for service, resale, and claims.
PART VII–IX: CONSOLIDATION
You can now keep people safe and put a system in the ground or on a roof and keep it running. That means working at height and around always-live DC and batteries without getting hurt (Part VII), surveying a site and executing the mechanical and electrical install to spec (Part VIII Ch 30–32), commissioning it to IEC 62446-1 for inspection and PTO (Ch 33), and monitoring, troubleshooting, and maintaining it across a 30-year life (Part IX). Combined with Parts I–VI, this is the complete technical competence of a professional installer.
Part X steps out of the technical and into the business: the economics, incentives, sales, permitting, and project management that turn competence into a livelihood. Part XI then maps the industry and the career itself.
Technical skill installs a system; business skill sustains a livelihood. This part covers the money, the paperwork, and the process. ⚠️ The incentive chapter (38) is the most time-sensitive material in this primer: federal solar policy changed dramatically in 2025, and the specific values and deadlines below are stated as of mid-2026 and must be re-verified before relying on them.