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 Day4 Energy

Here are the PSI Ratings for modules from Day4 Energy, 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	Day4 Energy	Day4 60MC-I 250	Polycrystalline	250	7.61*	55
2	Day4 Energy	Day448MC 190	Polycrystalline	190	7.50*	48
3	Day4 Energy	Day4 60MC-I 245	Polycrystalline	245	7.46*	45
4	Day4 Energy	Day4 60MC-I 240	Polycrystalline	240	7.32*	37
5	Day4 Energy	Day448MC 185	Polycrystalline	185	7.31*	36
6	Day4 Energy	Day4 60MC-I 235	Polycrystalline	235	7.12*	27
7	Day4 Energy	Day448MC 180	Polycrystalline	180	7.11*	26
8	Day4 Energy	Day4 60MC-I 230	Polycrystalline	230	6.98*	20
9	Day4 Energy	Day448MC 175	Polycrystalline	175	6.91*	18
10	Day4 Energy	Day4 60MC-I 225	Polycrystalline	225	6.81*	15
11	Day4 Energy	Day448MC 170	Polycrystalline	170	6.71*	12
12	Day4 Energy	Day4 60MC-I 220	Polycrystalline	220	6.68*	11
13	Day4 Energy	Day4 60MC-I 215	Polycrystalline	215	6.55*	8
14	Day4 Energy	Day448MC 165	Polycrystalline	165	6.51*	8
15	Day4 Energy	Day4 60MC-I 210	Polycrystalline	210	6.39*	6
16	Day4 Energy	Day448MC 160	Polycrystalline	160	6.28*	5
17	Day4 Energy	Day4 60MC-I 205	Polycrystalline	205	6.22*	4
18	Day4 Energy	Day448MC 155	Polycrystalline	155	6.11*	4

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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.