Solar Panel Warranty Guide for Bihar
Understanding the three types of solar warranties helps you make better decisions and ensures you know exactly what is covered by whom. This guide applies to all on-grid rooftop solar systems installed in Bihar.
Three Types of Solar Warranties
- Manufacturing defects
- Delamination and cell defects
- Junction box and connector failures
- Frame and glass integrity issues
- Physical damage from external causes
- Damage from improper installation
- Acts of nature (hail, flood)
- ≥97% of rated power at year 1
- ≥90% of rated power at year 10
- ≥80% of rated power at year 25
- Degradation not exceeding 0.5%/year
- Performance loss due to shade
- Soiling or dirt accumulation
- Improper tilt or orientation
- Wiring and cable quality
- Mounting structure integrity
- Roof waterproofing at penetration points
- Earthing and protection systems
- Panel or inverter product defects
- Performance warranty claims
- Damage from external events
Inverter Warranty
Grid-tied inverters are typically warranted by the manufacturer for 5 years. Extended warranty options (up to 10 years) are available from most Tier-1 brands at additional cost. Unlike solar panels which last 25+ years, inverters typically have a lifespan of 10–15 years and may need replacement during the panel's lifetime.
What to Check at Project Handover
Ask your installer to provide all of these at handover:
- Original panel manufacturer invoice with serial numbers
- Panel product warranty certificate (from manufacturer)
- Panel performance warranty document
- Inverter warranty card / registration confirmation
- Earthing test report (< 5 Ohm resistance reading)
- Net-metering / generation meter commissioning receipt
- DISCOM net-metering approval letter
- As-built wiring diagram / system layout drawing
- Installer workmanship warranty document (if provided)
- IoT monitoring app login credentials
Frequently Asked Warranty Questions
Product warranty covers physical defects in the panel (like delamination, cracking or junction box failure) for typically 10–12 years. Performance warranty guarantees the panel will generate at or above a certain power output (usually ≥80% of rated power at year 25). Both are different documents from the module manufacturer.
Product and performance warranties are issued directly by the panel manufacturer (e.g., Waaree, Adani Solar, Vikram Solar) and are separate from the installer. The installer provides a workmanship/installation warranty covering the civil work, wiring and structure. Always check both documents at the time of project handover.
Workmanship warranty covers defects arising from the installation process itself — improper wiring, mounting structure failure, roof waterproofing damage, or earth connection issues. This is the responsibility of the installing company, not the manufacturer.
Standard inverter warranty is 5 years from most Tier-1 brands like Growatt, Solis and Delta. Extended warranty options (up to 10 years) are available from most manufacturers at additional cost. Inverters typically have a shorter lifespan than panels and may need replacement around year 10–12.
You need to raise a warranty claim directly with the module manufacturer through their official warranty portal or service network. The installer cannot process manufacturer warranty claims on your behalf, but should provide you with all original documentation and invoice copies at handover to support future claims.