Best Solar Panel Warranty Guide for Installers for 2026
- Sarah Lozanova
- Dec 23, 2025
- 7 min read
Updated: 47 minutes ago
Table of Contents
Installing a solar system is a major investment, often costing tens of thousands of dollars. The solar panels are usually the most expensive part of a PV system, which makes having a strong solar panel warranty essential for protecting long-term performance. Panels work under tough conditions—scorching heat, freezing winters, hail, heavy winds, and daily UV exposure, yet most solar panels are reliable.
With more than a decade of experience supporting solar permitting and engineering nationwide, GreenLancer has seen firsthand how the best solar panel warranties protect installers and homeowners from costly surprises. Understanding solar panel installation warranties, how coverage differs by manufacturer, and what happens when issues arise helps installers specify equipment confidently, manage liability, and set clear expectations with customers.
What Is A Solar Panel Warranty?
A solar panel warranty is a manufacturer's guarantee covering defects and performance issues. Typically lasting 10 to 25 years, it assures customers that the PV panels will meet specified standards. Solar panel warranties provide repair or replacement coverage for any issues that arise during the warranty period, serving as a form of consumer protection.
For residential solar systems, warranties usually focus on protecting homeowners from early panel failures or underperformance. For commercial solar installations, warranties are often more comprehensive, reflecting the higher system size and investment value. They can include extended coverage for performance, inverter replacements, and workmanship.
Typically, premium PV panels offer longer product warranties and stronger power performance guarantees. Many solar companies sell both a value panel and a premium panel, so customers can choose which one they want. The biggest difference between value and premium panels is usually the solar panel efficiency and the warranties.
Types of Solar Panel Warranties
There are three primary types of solar panel warranty coverage. Understanding how each one applies is essential for selecting equipment with the best solar panel warranty coverage and managing solar installation warranty liability.
Homeowner’s or commercial property insurance may also cover certain types of damage, such as fire, hail, or vandalism, but these events typically fall outside standard solar panel warranty claims.
Performance Warranty (Power Output Guarantees)
PV modules are regularly exposed to environmental conditions, which can lead to decreased efficiency in converting sunlight into electricity over time due to light-induced degradation.
A solar panel warranty typically includes power performance guarantees that ensure panels maintain a certain percentage of their original capacity over specified periods. For instance, a common guarantee states that panels will generate at least 90% of their initial capacity for 10 years and 80% for 25 years, as the manufacturer specifies.
However, solar panel warranties often vary across product lines from the same manufacturer, with some offering enhanced terms for specific models. For instance, the Jinko Tiger N-type panel comes with a power performance guarantee of 30 years, thanks to its lower rate of light-induced degradation. This extended warranty surpasses the typical 25-year coverage provided for other Jinko panels, making it one of the best solar panel warranty options available.
How Solar Performance Guarantees Work
Understanding how a solar panel warranty's performance guarantee works can be difficult to decipher. The guarantee is generally stated as a percentage of the nominal power in the first year and then a yearly decrease in power up to a certain percentage.
For example, Q Cells states 98% nominal power in the first year, and then the nominal decrease in output is not to exceed 0.5% annually from years 2 to 25. To calculate this solar panel warranty, remember that the nominal power in year one is calculated differently from years 2 to 25. Therefore, the minimum nominal power after 25 years is 86%. To calculate this: 0.86 = 0.98 - (24 x 0.005)
If you want to calculate the nominal power output after 11 years is: 0.93 = 0.98 - (10 x 0.005)
Keep in mind that sometimes solar panels underperform because they need to be cleaned, which isn't a solar panel warranty issue. Heavily soiled modules can produce less electricity because the solar radiation is blocked.
Solar Panel Warranty: Product & Materials Coverage
Product and materials warranties cover defects in manufacturing, materials, and workmanship of the solar module itself. While 10- or 12-year product warranties were once standard, many manufacturers now offer 20- or 25-year coverage, particularly on premium product lines.
Warranty length and terms can vary by model within the same brand. Installers should review product-specific documentation closely, especially when comparing options like Canadian Solar warranty, Mission Solar warranty, or extended coverage programs from manufacturers such as Silfab and REC.
Some solar module manufacturers provide flexible warranty options, making it easier to find the best solar panel warranty for your needs. For example, Silfab offers a standard 12-year warranty on solar panels with the option to extend it to 25 years when using a registered and approved Silfab solar installer. Likewise, REC offers a 20-year solar panel warranty for all installers and a 25-year product warranty for REC-certified contractors.
* Minimum warranty period length or power performance guarantee varies by the series
Solar Panel Warranty: Labor Warranties
While most PV modules include a solar panel installation warranty for the equipment itself, labor costs are often excluded. Replacing malfunctioning modules can be labor-intensive, requiring trained technicians to access rooftops, remove panels, and reinstall equipment safely. As a result, labor can represent a significant portion of total solar installation warranty liability when issues arise.
To address this gap, many solar companies offer separate labor warranties that cover labor reimbursement for solar warranty claims over a defined period, typically ranging from 1 to 10 years. For both residential and commercial projects, labor coverage can play a key role in providing the best solar panel warranty for installers, helping reduce out-of-pocket repair costs and improve long-term customer satisfaction.
What a Solar Panel Warranty Covers
A solar panel warranty typically covers manufacturer defects and premature light-induced degradation. If issues arise, manufacturers often address warranty claims by either repairing the defect, replacing the faulty panel, or refunding the original purchase price of the module. This coverage ensures that consumers are protected against unforeseen problems that could affect the performance of their solar investment.
However, proper installation plays a vital role in maintaining warranty coverage. For instance, ensuring that the racking system is adequate for the wind load of the project site can help prevent damage to the solar panels. Additionally, it's essential to diagnose whether the issue lies with the solar panel itself or if it stems from other components, such as the inverter or power optimizer.
What Can Void a Solar Panel Warranty
Several factors can potentially void warranties on solar panels, leaving consumers unprotected against defects or performance issues.
Here are some common reasons:
Improper Installation:Â Modules not installed according to the manufacturer's specifications can void a solar panel warranty. This includes failure to use the recommended mounting equipment or improper wiring.
Lack of Maintenance:Â Lack of regular solar maintenance, such as cleaning the panels or inspecting for damage, can lead to issues that may not be covered under the warranty. Neglecting to maintain the system could decrease efficiency and void the warranty.
Environmental Damage:Â Damage caused by extreme weather events, such as hurricanes, hail, or floods, may also void a solar panel warranty, especially if the installation is not adequately protected or reinforced.
Modifications or Repairs:Â Unauthorized modifications or repairs to the solar system can void the warranty. For instance, if a third-party technician attempts to repair or alter the solar panels, this action could invalidate the warranty.
Not Registering the Solar Panel Warranty:Â Some manufacturers require that customers register their warranties on solar panels within a certain timeframe. Not doing this may result in the solar panel warranty being voided.
Vandalism or Theft: Damage caused by vandalism or malicious acts typically falls outside the warranty coverage. This includes any intentional damage and solar panel theft.
Solar Panel Warranty Costs
Most solar panel warranties are included in the upfront cost of the modules and do not carry a separate fee. The primary exception is optional extended coverage, which is uncommon for solar panels but more frequently offered for inverters or other balance-of-system components. From an installer's perspective, these costs are typically embedded in the overall solar panel installation warranty structure rather than itemized separately.
In practice, clients are more likely to rely on homeowner’s or commercial property insurance for events that fall outside standard warranty coverage, such as hail or storm damage. Increasing insurance limits to account for the PV system may result in a modest premium increase. If a claim is filed, customers must meet their insurance deductible before coverage applies, which can factor into overall solar installation warranty liability discussions.
For example, with a $500 deductible and $3,000 in hail-related damage to a solar PV system, insurance would typically cover the remaining $2,500 after the deductible is satisfied.
Why Solar Panel Warranties Are Important
Investing in solar panel systems typically costs thousands or even tens of thousands of dollars. While these systems can lead to substantial savings over time, those benefits can be jeopardized if the system malfunctions. A warranty on solar panels provides customers with peace of mind, assuring them that their investment is protected against potential defects and performance issues.
Also, offering a labor and workmanship warranty for several years is essential. This coverage protects customers from additional costs associated with installation errors and helps ensure that necessary repairs are handled promptly.
Educating customers about solar panel warranties can facilitate closing deals and enhance their understanding of what they are purchasing. When designing photovoltaic (PV) systems, consider warranty options as a critical factor before finalizing equipment choices. Collaborating with companies like GreenLancer can further streamline the process by providing expertise in PV design, permitting, and engineering support.
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FAQs on Solar Panel Warranties
Get answers to your most common questions on PV module warranties.