Khawar Nehal’s Solar Panel Grading Criteria.Version 0.4

Date : 25 November 2018

http://atrc.net.pk

khawar@atrc.net.pk

+ 92 331 2036 422

Modules A Grade : Visual Appearance : Perfect. No flaws can be detected from max 1 feet away. Power : The power is within -2% to +10% of the tested rated power.

Color variation : Almost not noticeable.

Broken Glass : None Short Circuits : None

Modules B Grade : Visual Appearance : Some minor cosmetic flaws or issues. Flaws are apparent from withing 1 to 7 feet away. Flaws can not be detected from more than 7 feet away by comparing to an A grade flawless panel.

Tested power : -10% to +2% of rated power.

Price : Up to 35% less than A grade.

Broken Glass : None Short Circuits : None

Modules C Grade : Visual Appearance : Highly apparent visual flaws. Flaws are apparent from more than 7 feet away.

Tested power : -20% to +2% of rated power.

Power : Same as A grade. The power is within +- 5% of the tested rated power.

Price : Up to 50% less than A grade. Broken Glass : None Short Circuits : None Cells with horizontal cracks which intersect all the bus bars on the surface of the cell : PossibleNot recommended for high voltage applications. Can be used for less than 50V applications. Solar cells with microcracks : Plenty

Modules D Grade : Visual Appearance : Broken glass. Can be repaired. No peneration of dust or water. Flaws are apparent from more than 7 feet away.

Tested power : -30% to +2% of rated power.

Price : Up to 80% less than A grade.

Broken Glass : YesShort Circuits : PossibleCells with horizontal cracks which intersect all the bus bars on the surface of the cell : PossibleNot recommended for any application until repaired.Solar cells with microcracks : Plenty

Modules E Grade : Visual Appearance : Broken glass. Can be repaired by taking the whole solar panel apart and rebuilding. Shows penetration of dust or water. Flaws are apparent from more than 7 feet away.

Tested Power : Not to be tested in this dangerous condition. No testing should be done without full repairs.

Price : Up to 95% less than A grade.

Broken Glass : YesShort Circuits : YesCells with horizontal cracks which intersect all the bus bars on the surface of the cell : DefinitelyNot recommended for any application until completely rebuilt.Solar cells with microcracks : Plenty

Manufacturer time in the market : A Grade : At least 10 years. B Grade : At least 5 years C grade : At least 3 years D Grade : At least 1 year E Grade : Less than 1 year.

Supplier time in the market grading : A Grade : At least 10 years. B Grade : At least 5 years C grade : At least 3 years D Grade : At least 1 year E Grade : Less than 1 year. Supplier reliability : A : Grade At least three references which favor the supplier and are known by the buyer in the market for credibility. All three references have nothing bad to say about the supplier when asked.

B : Grade At least 2 references which favor the supplier and are known by the buyer in the market for credibility. All 2 references have nothing bad to say about the supplier when asked.

C : Grade At least 1 references which favor the supplier and are known by the buyer in the market for credibility. The references have nothing bad to say about the supplier when asked.

Power guarantee : A Grade : Minimum 90% power up to 12 years into the future after sales date. Minimum 80% power up to 25 years into the future after sales date. Guarantee method : Supplier directly imports from the manufacturer and is trusted by the buyer to make sure the warranty is not at risk.

B Grade : Power guarantee : Minimum 90% power up to 5 years into the future after sales date. Minimum 80% power up to 10 years into the future after sales date. Guarantee method : Supplier buys from a reliable importer or distributor is trusted by the buyer to make sure the warranty is not at risk.

C Grade : Power guarantee : Minimum 80% power up to 5 years into the future after sales date.

D Grade : Power guarantee : Minimum 80% power up to 3 years into the future after sales date.Power guarantee : Guaranteed by the shop. Direct link to manufacturer or distributor not checked or not verifiable.

E Grade : Power guarantee : Minimum 80% power up to 1 years into the future after sales date.Guarantee method : Guaranteed by a trusted and reliable shop. Direct link to manufacturer or distributor not checked or not verifiable.

F Grade : No guarantee

Manufacturing defect guarantee : A Grade : Up to 12 years into the future after sales date. Guarantee method : Supplier directly imports from the manufacturer and is trusted by the buyer to make sure the warranty is not at risk.

B Grade : Up to 10 years into the future after sales date. Guarantee method : Supplier buys from a reliable importer or distributor is trusted by the buyer to make sure the warranty is not at risk.

C Grade : Up to 5 years into the future after sales date. Guarantee method : Supplier buys from a reliable importer or distributor is trusted by the buyer to make sure the warranty is not at risk.

D Grade : Up to 3 years into the future after sales date. Guarantee method : Guaranteed by a trusted and reliable shop. Direct link to manufacturer or distributor not checked or not verifiable.

E Grade : Up to 1 years into the future after sales date. Guarantee method : Guaranteed by a trusted and reliable shop. Direct link to manufacturer or distributor not checked or not verifiable.

F Grade : No guarantee

Solar Cells A Grade Chipping of solar cells on the sides : Max 1mm x 1mmCells with horizontal cracks which intersect all the bus bars on the surface of the cell : None Solar cells with microcracks : NoneMaximum bending : Less than 2 millimeters.

Solar Cells B Grade Visual Appearance : Some minor cosmetic flaws or issues.Cells with horizontal cracks which intersect all the bus bars on the surface of the cell : None (Hot spot creation potential in high voltage arrays with even a little shading)Solar cells with microcracks : Some

Solar Cells C Grade Visual Appearance : Highly apparent visual flaws. Cells with horizontal cracks which intersect all the bus bars on the surface of the cell : Possible

Solar Cells D Grade Cells with horizontal cracks which intersect all the bus bars on the surface of the cell : Possible (Hot spot creation potential in high voltage arrays with even a little shading) Solar Cells E Grade Broken Solar CellsCan be wired into DIY Projects.

Manufacturer Ratings

Tier 1 Quantity manufactured : The manufacturer is in the top 50 of Manufacturers by quantity. Usually this means producing above 1GW per year. Process : Vertically integrated from silicon to panelsR&D Spending : More than 2% of revenue. History : More than 10 years of manufacturing operations. Solar Panel Manufacturing defects warranty : 10 or more years. Solar Cells in Panels Power warranty : Minimum 80% of rated power for a minimum of 25 years.

Tier 2Quantity manufactured : Small to medium scale 100MW to 1 GW per year. Process : Not complete. Buy Cells from others and make the modules. R&D Spending : 0 to 2% of revenue. History : More than 5 years of manufacturing operations. Solar Panel Manufacturing defects warranty : 5 or more years. Solar Cells in Panels Power warranty : Minimum 80% of rated power for a minimum of 10 years.

Tier 3Quantity manufactured : Less than 100MW per year.Process : Not complete. Buy Cells from others and make the modules. R&D Spending : 0 to 2% of revenue. History : More than 2 years of manufacturing operations. Solar Panel Manufacturing defects warranty : 1 or more years. Solar Cells in Panels Power warranty : Minimum 80% of rated power for a minimum of 5 years.

If you have a better idea or can help improve the standards. Feel free to email me.