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 UE Solar

Here are the PSI Ratings for modules from UE Solar, 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	UE Solar	ZHM-60-260P	Polycrystalline	260	8.11*	80
2	UE Solar	ZHM280P	Polycrystalline	280	7.96*	73
3	UE Solar	ZHM-60-255P	Polycrystalline	255	7.95*	73
4	UE Solar	ZHM275P	Polycrystalline	275	7.80*	65
5	UE Solar	ZHM-60-250P	Polycrystalline	250	7.79*	65
6	UE Solar	ZHM-60-245P	Polycrystalline	245	7.68*	58
7	UE Solar	ZHM270P	Polycrystalline	270	7.67*	58
8	UE Solar	ZHM265P	Polycrystalline	265	7.53*	49
9	UE Solar	ZHM-60-240P	Polycrystalline	240	7.53*	49
10	UE Solar	ZHM260P	Polycrystalline	260	7.39*	41
11	UE Solar	ZHM-60-235P	Polycrystalline	235	7.37*	39
12	UE Solar	ZHM185	Monocrystalline	185	7.31*	36
13	UE Solar	ZHM255P	Polycrystalline	255	7.25*	33
14	UE Solar	ZHM-60-230P	Polycrystalline	230	7.21*	31
15	UE Solar	ZHM230P	Polycrystalline	230	7.15*	28
16	UE Solar	ZHM180	Monocrystalline	180	7.11*	26
17	UE Solar	ZHM250P	Polycrystalline	250	7.10*	26
18	UE Solar	ZHM225P	Polycrystalline	225	6.97*	20
19	UE Solar	ZHM245P	Polycrystalline	245	6.96*	19
20	UE Solar	ZHM175	Monocrystalline	175	6.91*	18
21	UE Solar	ZHM240P	Polycrystalline	240	6.83*	15
22	UE Solar	ZHM220P	Polycrystalline	220	6.82*	15
23	UE Solar	ZHM235P	Polycrystalline	235	6.75*	13

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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.