Solar panels come with two main warranties: a product warranty covering defects and workmanship, and a performance warranty guaranteeing minimum power output over time. In Singapore, a good product warranty lasts 25 years for premium brands like REC and Panasonic, while performance warranties typically promise at least 85% of original power after 25 years. Understanding these warranties—and the installer’s own workmanship guarantee—protects your landed home investment. Use this checklist to compare offers and spot potential gaps.
Product Warranty vs. Performance Warranty
Product Warranty
This covers manufacturing defects, premature wear, and material failures. Standard term is 12 to 15 years for mass-market panels, while top-tier panels from REC (Alpha Pure-RX) and Panasonic (EverVolt) carry 25-year product warranties. If a panel fails within this period, the manufacturer will repair or replace it. Some manufacturers also cover the labour to swap the panel, but that’s not universal—check the fine print.
Performance Warranty
This guarantees the panel will still produce a set percentage of its rated power after a certain number of years. A typical two-tier promise: at least 97% of rated power in the first year, then a maximum 0.5% annual degradation, reaching 85% at year 25. Cheaper panels may start with a 2.5% first-year drop and 0.7% annual degradation, ending at 80% at year 25. That 5% difference in output over 25 years represents thousands of dollars in lost electricity savings for a typical landed home system.
Key Warranty Terms to Compare
| Brand | Product Warranty (Years) | Performance Warranty (End Year 25) | Annual Degradation Rate |
|---|---|---|---|
| REC Alpha Pure-RX | 25 | ≥ 92% (linear performance guarantee) | 0.25% |
| Panasonic EverVolt HK | 25 | ≥ 92% | 0.25% |
| Trina Vertex S+ | 15 | ≥ 84.8% | 0.55% |
| Jinko Tiger Neo | 15 | ≥ 84.8% | 0.55% |
| Longi Hi-MO 6 | 15 | ≥ 84.8% | 0.55% |
Data sourced from manufacturers’ 2025–2026 datasheets and warranty statements accessible on official product pages.
What Many Homeowners Overlook
Warranty Exclusions
Almost all manufacturers exclude damage from external causes like falling branches, lightning, and improper installation. If your installer uses a non-approved mounting system that stresses the frame, the warranty is void. That’s why I always use mounting kits listed in the manufacturer’s installation manual. Also, panels installed within 500 metres of the sea—such as in Sentosa or East Coast landed properties—may need salt mist certification. Not all panels carry that certification. Using a standard panel near the coast without approval can void the product warranty.
Installer Workmanship Warranty
A solar system is only as reliable as the installation. Reputable solar companies in Singapore offer a 2- to 5-year workmanship warranty on top of manufacturer warranties. This covers roof leaks caused by the mounting system, faulty wiring, and inverter commissioning errors. Ask for a written workmanship warranty that names the duration, what is covered, and response time for service calls. In my practice, I issue a 5-year workmanship warranty covering the entire DC and AC side of the installation.
Inverter and Optimiser Warranties
String inverters usually come with a 5-year product warranty, extendable to 10 or 20 years at extra cost. Microinverters, like those from Enphase, often include a 25-year warranty. Power optimisers from SolarEdge carry a 25-year warranty when registered online. Your system’s weakest warranty link determines the likely repair cost. Factor this into your comparison.
Checklist Before Signing a Solar Contract
- Does the panel product warranty extend to at least 15 years, preferably 25?
- What is the year-25 guaranteed output percentage? Insist on ≥ 84.8% as a minimum.
- Is the annual degradation rate stated as a linear guarantee or a stepped guarantee? Linear is more transparent.
- Does the manufacturer have a local office or authorised service partner in Singapore to handle warranty claims quickly?
- What does the installer’s workmanship warranty cover, and for how long?
- Are the inverter and power electronics warranties aligned with the panel life, or will you budget for a replacement at year 10?
- If your roof is near the coast, ask for a salt mist certification letter from the panel maker.
- Request a copy of the panel manufacturer’s warranty certificate with the serial numbers of your panels after installation.
Expert Tip: Future-Proofing Through Warranty Strength
I encourage landed homeowners to think of the warranty as an insurance policy. A slightly higher upfront cost for a 25-year product warranty panel with 0.25% degradation often yields a better levelised cost of electricity than a cheaper panel that degrades faster and may need replacement at year 15. If you ever sell your home, an existing solar system with a fully transferrable, long-dated warranty adds to property appeal. Both REC and Panasonic warranties are transferrable to a new homeowner, which is a strong resale advantage. Confirm the transfer process with the manufacturer before installation.
Before you commit, Enquire with Akando Solar for a detailed warranty comparison on the panel models we recommend for your specific roof. We also cover the full workmanship warranty on every landed project.
Browse our Residential solar panel selection to see which high-warranty panels fit your home.
References
- REC Group, Warranty & Product Certificates, https://www.recgroup.com/en/warranty
- Panasonic Solar, Warranty Information, https://na.panasonic.com/us/energy-solutions/solar/warranty
- Trina Solar, Warranty & Degradation, https://www.trinasolar.com/sg/resources/warranty
- JinkoSolar, Limited Warranty, https://www.jinkosolar.com/en/support/warranty/