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.

Subscribe to our email list

Before using the PSI Ratings, you should subscribe to our email list to receive important updates from the Principal Solar Institute.

PSI Ratings – PV Solar Modules from alfasolar

Here are the PSI Ratings for modules from alfasolar, 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	alfasolar	alfasolar M6L60-265	Monocrystalline	265	8.61*	93
2	alfasolar	alfasolar M6L60-260	Monocrystalline	260	8.44*	90
3	alfasolar	alfasolar M6L60-255	Monocrystalline	255	8.27*	86
4	alfasolar	alfasolar M6L60-250	Monocrystalline	250	8.04*	77
5	alfasolar	alfasolar P6L60-250	Polycrystalline	250	7.96*	73
6	alfasolar	alfasolar M6L60-245	Monocrystalline	245	7.88*	70
7	alfasolar	alfasolar P6L60-245	Polycrystalline	245	7.79*	65
8	alfasolar	alfasolar M6L60-240	Monocrystalline	240	7.73*	61
9	alfasolar	alfasolar P6L60-240	Polycrystalline	240	7.63*	56
10	alfasolar	alfasolar P6L60-235	Polycrystalline	235	7.47*	46
11	alfasolar	alfasolar P6L60-230	Polycrystalline	230	7.26*	34
12	alfasolar	alfasolar P6L60-225	Polycrystalline	225	7.11*	26
13	alfasolar	alfasolar P6L60-220	Polycrystalline	220	6.96*	19

---

* 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.