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
1	Webel SL Energy Systems	W 2300-240 Wp	Monocrystalline	240	7.35*	38
2	Webel SL Energy Systems	W 2100-220 Wp	Monocrystalline	220	7.29*	35
3	Webel SL Energy Systems	W 2300-235 Wp	Monocrystalline	235	7.20*	31
4	Webel SL Energy Systems	W 2100-215 Wp	Monocrystalline	215	7.12*	27
5	Webel SL Energy Systems	W 1750-180 Wp	Monocrystalline	180	7.10*	26
6	Webel SL Energy Systems	W 2300-230	Monocrystalline	230	7.05*	23
7	Webel SL Energy Systems	W 2100-210 Wp	Monocrystalline	210	6.96*	19
8	Webel SL Energy Systems	W 1750-175 Wp	Monocrystalline	175	6.90*	17
9	Webel SL Energy Systems	W 1750-170 Wp	Monocrystalline	170	6.56*	9

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* 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.