Principal Solar Institute

A community for development and installation professionals in the solar industry

The Principal Solar Institute Module Ratings

The Principal Solar Institute’s scientifically designed and certified combination of tests and performance standards provide an unbiased, comprehensive rating system – the PSI PV module rating. Seven essential characteristics related to initial and long-term PV module performance are combined to create the PSI Rating:

  • Actual Tested Maximum Power vs. Advertised
  • Temperature Coefficient at Maximum Power
  • Power at Low Irradiance to Power at High Irradiance Ratio
  • Normal Operating Cell Temperature (NOCT)
  • Total Area Efficiency
  • Negative Power Tolerance
  • Annual Power Reduction

These ratings allow you to make comparisons when analyzing PV modules and help you select the optimal PV module.

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PSI Ratings – PV Solar Modules from Webel SL Energy Systems

Here are the PSI Ratings for modules from Webel SL Energy Systems, calculated based on initial performance test data. If you don’t see a solar module that you are considering, contact us and we will try to add it.

Rank Manufacturer Model Type Power
(W DC)
PSI Rating Percentile
1Webel SL Energy SystemsW 2300-240 WpMonocrystalline2407.35*38
2Webel SL Energy SystemsW 2100-220 WpMonocrystalline2207.29*35
3Webel SL Energy SystemsW 2300-235 WpMonocrystalline2357.20*31
4Webel SL Energy SystemsW 2100-215 WpMonocrystalline2157.12*27
5Webel SL Energy SystemsW 1750-180 WpMonocrystalline1807.10*26
6Webel SL Energy SystemsW 2300-230Monocrystalline2307.05*23
7Webel SL Energy SystemsW 2100-210 WpMonocrystalline2106.96*19
8Webel SL Energy SystemsW 1750-175 WpMonocrystalline1756.90*17
9Webel SL Energy SystemsW 1750-170 WpMonocrystalline1706.56*9

* Modules denoted with an “*” use estimated values for one or more characteristics. Manufacturers can contact us to provide the missing data for these PV modules.

NOTE: PSI Ratings are based on publicly available data, and are subject to change as additional data and proprietary analyses become available for long-term performance.