A solar performance audit is the most diagnostic tool available for understanding your plant true health. Unlike a routine maintenance visit, an audit systematically tests every component.
What Is a Solar Performance Audit?
A solar performance audit is the most diagnostic tool available for understanding your plant true health. Unlike a routine maintenance visit, an audit systematically tests every component and compares actual performance against theoretical potential.
For plant owners in India, where solar assets often run for years without independent assessment, a performance audit typically reveals 5–20% recoverable losses — generation that is being lost right now but can be fixed.
What a 30-Point Solar Performance Audit Covers
Visual and Physical Inspection (Points 1–10)
- Panel glass condition — cracks, delamination, bubbling
- Frame integrity and corrosion
- Junction box sealing and condition
- Cable routing and support
- MC4 connector condition and locking
- Mounting structure integrity
- Earthing connections and continuity
- Cable management — UV and rodent protection
- Inverter physical condition and ventilation
- AC distribution board condition
Electrical Testing (Points 11–22)
- Open circuit voltage (Voc) per string
- Short circuit current (Isc) per string
- IV curve tracing — identifies degraded panels per string
- Insulation resistance (IR) test — all DC strings to earth
- Earth leakage test (AC side)
- String voltage balance
- Inverter input parameters — MPPT voltage ranges
- Inverter output parameters — power factor, THD
- Grid voltage and frequency verification
- Protection relay settings verification
- Surge protection device status
- MCB rating verification
Thermal Imaging (Points 23–26)
- Full-plant panel thermography
- Junction box thermal scan
- Connector thermal scan
- Inverter thermal profile
Performance Analysis (Points 27–30)
- Historical generation vs. design generation (PR analysis)
- Shading analysis
- Specific yield calculation and benchmark comparison
- Degradation rate estimation based on historical data
How to Interpret the Results
Performance Ratio (PR)
- PR above 75%: Good. System is performing within acceptable parameters.
- PR 65–75%: Below standard. Investigation needed.
- PR below 65%: Significant underperformance. Multiple issues likely.
Indian C&I plants with no professional maintenance typically show PR in the 65–72% range. After SolarTrust intervention, we typically bring plants to 78–83% PR within 60 days.
What a Solar Performance Audit Costs in India
- Free audit: SolarTrust offers a free 30-point audit for all plants being considered for an AMC plan
- Standalone audit (up to 100kW): Rs. 5,000–10,000
- Standalone audit (100kW–1MW): Rs. 10,000–25,000
- Large plant audit (1MW+): Rs. 25,000–75,000 depending on capacity
All audit prices include the full 30-point assessment, thermal imaging, and written report.
When to Commission a Performance Audit
- Immediately if your plant has never had a professional audit
- Immediately if generation has dropped more than 10% year-over-year
- Immediately if you are acquiring or selling a solar plant
- Annually as part of your preventive maintenance cycle
- Before warranty expiry to document the plant condition