What Solar Warranties Should Filipino Homeowners Check Before Buying?

Going solar is a big investment. For most Filipino homeowners, it ranks right up there with renovating a house or buying a car. So before you sign anything or hand over a downpayment, there's one part of the deal that deserves more attention than it usually gets: the warranty.

Most buyers spend a lot of time comparing panel wattage and upfront costs. The warranty documents? They get a quick glance and a nod. That's a mistake.

A solar system is something you're supposed to live with for 25 to 30 years. The warranty is what protects you during that entire period. Here's what you actually need to check before buying.

There Are Four Separate Warranties, Not One

This is the part most homeowners miss. When a solar company says "25-year warranty," that doesn't mean everything is covered for 25 years. A solar system has multiple components, and each one carries its own warranty with its own terms.

Here are the four warranties you need to ask about:

1. Solar Panel Product Warranty

This covers physical defects in the solar panels themselves. We're talking about frame damage, delamination (when the panel layers start peeling apart), faulty junction boxes, or manufacturing defects that cause early failure.

The industry standard for quality panels has been moving upward. A decade ago, 10 years was common. Today, reputable brands offer product warranties of 15 to 25 years. For Tier 1 panels from brands like LONGi, JinkoSolar, or Canadian Solar, a 25-year product warranty is increasingly the baseline.

What to watch out for: warranty cards that are vague about what counts as a "defect" and what doesn't. Read the exclusions.

2. Solar Panel Performance Warranty

This is separate from the product warranty and often more important in the long run. All solar panels lose a small percentage of their output over time, a process called degradation. The performance warranty puts a cap on how much degradation is acceptable.

A typical performance warranty guarantees that your panels will still produce at least 80% of their rated output after 25 years. Better panels will guarantee 85 to 90%. The first-year degradation rate is also worth checking. Some manufacturers allow up to 3% in year one, while premium panels cap it at 1 to 2%.

If your panels degrade faster than the warranty allows, the manufacturer owes you replacement or compensation. But only if you have this in writing.

3. Inverter Warranty

Your inverter is the component that converts the DC power your panels generate into the AC power your home actually uses. It works constantly, every day, which means it wears out faster than your panels.

Standard inverter warranties run from 5 to 12 years depending on the brand and type. String inverters from brands like Growatt or Solis typically come with 5 to 10 years. Hybrid inverters may carry 5 to 7 years. Some premium microinverter brands go longer.

The gap between a 25-year panel life and a 5 to 10-year inverter warranty means you will likely need to replace or repair your inverter at least once during the life of your solar system. Factor this cost into your budget when comparing proposals.

4. Workmanship or Installation Warranty

This one comes from your solar installer, not the manufacturer. It covers problems caused by how the system was installed: improper wiring, roof penetrations that weren't sealed correctly, mounting that wasn't done right, and so on.

Installation warranties in the Philippines typically run from 1 to 5 years. One year is the bare minimum. Anything less than that should raise a flag.

This warranty matters a lot because installation errors are not always visible right away. Some problems only show up after the first heavy rain or after a strong typhoon hits your area.

What About Battery Warranties?

If your solar system includes battery storage, that's a fifth warranty to review.

Lithium iron phosphate (LiFePO4) batteries, the type most commonly used in Philippine residential solar systems today, are typically warranted for 3,000 to 6,000 charge cycles or 10 years, whichever comes first. Some premium brands go up to 15 years.

Pay attention to the cycle count and the capacity retention guarantee. A battery warranty that guarantees only 60% capacity retention at end of warranty is a weaker promise than one guaranteeing 80%.

Key Questions to Ask Before You Sign

Beyond just the number of years, ask these questions for every warranty:

Who backs the warranty? A manufacturer warranty is only as good as the manufacturer's ability to honor it. If the brand has no local distributor or service center in the Philippines, a 25-year warranty on paper may mean very little in practice. Ask where you file a claim and how long the response process takes.

Is the installer an authorized dealer? Buying from an unauthorized reseller can void your manufacturer warranty. Always confirm that your installer is an authorized dealer or certified installer for the brands they are proposing. If something breaks and your installer sourced the equipment through unofficial channels, you may be left with no manufacturer support.

What does the workmanship warranty cover exactly? Get this in writing. Does it cover roof damage caused by installation? What about wiring issues that show up two years later? Vague workmanship warranties are a common source of disputes.

Is local service available? Ask if the manufacturer has a regional service center or authorized service partners in the Philippines. According to a consumer guide from Solar Scout PH, your serial numbers and warranty certificates are your ticket to manufacturer support. Keep every document you receive at handover.

What happens if the installer closes down? This is a real risk in a growing market. If your installer shuts down, your workmanship warranty becomes worthless. Ask if the manufacturer's product and performance warranties can be claimed directly without the installer's involvement.

The DTI Is Now Tightening Solar Product Standards

Here's something worth knowing as a buyer. As of 2026, the Department of Trade and Industry (DTI) is pushing for mandatory product certification for solar energy systems sold in the Philippines.

According to reports from the Manila Bulletin and The Manila Times, the DTI's proposal would require solar panels, inverters, charge controllers, and battery storage systems to comply with Philippine National Standards (PNS) and carry a PS certification mark from the Bureau of Philippine Standards. The intent is to keep substandard and potentially unsafe equipment out of the market.

This is a move in the right direction. In the meantime, as a buyer, you can protect yourself by asking for proof that the equipment you're buying comes from verified Tier 1 manufacturers with a track record of honoring warranties globally.

You can read more about this development directly from Manila Bulletin and The Manila Times.

Why Your Installer's Credentials Are Part of the Warranty Picture

Here's something that often gets overlooked: the quality of your installer directly affects how meaningful your warranties are.

If your installer is not Department of Energy (DOE) accredited or does not hold a valid Philippine Contractors Accreditation Board (PCAB) license, you are taking on more risk than you might realize. DOE accreditation means the installer has met technical, financial, and regulatory requirements set by the country's highest energy authority. PCAB licensing is a legal requirement for construction contractors, and solar installation counts as construction work.

An installer without these credentials may still do decent work. But if something goes wrong and you need to escalate a complaint, your options become limited. The DOE's Renewable Energy Management Bureau (REMB) handles complaints related to accredited contractors. If your installer isn't in that system, that channel is closed to you.

Red Flags to Watch Out For

Vague warranty periods. "25-year warranty" with no breakdown of what it covers is not a warranty. Ask for the warranty document itself, not just a verbal assurance.

No local service presence. If the manufacturer has no office, distributor, or service partner in the Philippines, claims will be complicated and slow.

Warranty voiding conditions that are too broad. Some warranty documents include exclusions that practically nullify coverage. Read them carefully before signing.

Panels sourced from marketplace platforms. As noted by industry resources, solar panels purchased through Lazada or Shopee without a verifiable local distributor can make warranty claims nearly impossible to pursue.

Full payment required upfront. A reasonable payment structure is 30 to 50% downpayment, the bulk upon completion, and a final holdback upon net metering approval. Full upfront payment removes your leverage if installation quality issues come up later.

A Quick Warranty Checklist Before You Buy

Before you commit to any solar installation, check that you have clear answers to all of these:

• Solar panel product warranty: how many years and what defects are covered

• Solar panel performance warranty: guaranteed output percentage at year 10 and year 25

• Inverter warranty: duration and what happens when it expires before your panels do

• Workmanship warranty: duration, what's covered, and who covers it if the installer closes

• Battery warranty (if applicable): cycle count, years, and capacity retention guarantee

• Manufacturer's local service presence in the Philippines

• Installer's DOE accreditation and PCAB license status

  
  

Work With a Solar Company That Stands Behind Its Systems

At Solaready, we install solar panels across the Philippines for homes and businesses that want honest, long-term value from their investment. We walk every client through their warranty documents before installation begins, not after. No fine print surprises.

Whether you're comparing proposals or ready to move forward, we're here to help you make the right call.

Contact Solaready today for a free solar consultation. We'll review your options, explain every warranty term in plain language, and recommend a system that's built to last.

📞 Message or call us now to get started.

Solaready is a solar panel company in the Philippines offering residential and commercial solar installation with full warranty support and after-sales service.