Solar Panels Grades A, B, and C (Explained)

Different kinds of solar panels are better suited to different environments. The expensive monocrystalline panels vs. the cheaper polycrystalline or the easy-to-install thin-film solar panel may be the best for your needs.

And once you’ve figured out what kind of solar panels, made of which material, you need to decide what grade to get. There’s a lot to consider and figure out; however, understanding the properties and suitability of the different grades available is the first step to figuring out what you need.

What Is a Grade B Solar Panel?

Grade B solar panels have some visual defects that do not affect performance. Grade B naturally falls below grade A in this grading system. So how does Grade B stack up against the other grades?

Grade A solar panels are entirely free of defects. Grade B has some visual flaws but still meets performance standards. Grade C has visual and performance deficiencies, and Grade D is broken and unusable.

Naturally, this system leads to many interpretations of visual and performance defects. One company may not consider bends in solar panels defective, while another believes bends are flawed.

Before buying any grade of solar panels, take the time to read through the company’s standards for solar panels or listen to an explanation from an agent. A good solar company will have strict standards and a well-defined grading system the employees understand.

Some companies also have warranties on their grade B solar panels, the same as their grade A’s, and is a good indication of how confident the manufacturers are in the performance of the grade B solar panels. If you’re nervous about grade B solar panels’ performance, look for a business that sells them with warranties.

Ultimately, grade B solar panels have visual defects that wouldn’t do well in a conspicuous place but would do well in a less-trafficked area since they have no performance problems.

It all comes down to whether you want performance and visual appeal or if performance is the only thing that matters to you.

A, B, or C, the Grading System for Solar Panels

Like elementary school, solar panels are graded on several factors, mainly visual and performance flaws. While this grading system follows similar logic, different manufacturers and distributors can have other criteria for their grading systems.

Before buying any solar panels, please read up on the company you’re looking at to see their grading system and understand how they grade them. Some companies consider flaws in their product before grading, considering some of them defective and others okay.

Ultimately, it comes down to this: Grade A solar panels have no visual defects and meet performance standards. Grade B solar panels have some visible defects but meet performance standards.

Grade C solar panels have visual defects and do not meet performance standards. Grade D solar panels are unusable, and entirely broken.

See also: Types of Solar Panels: A Comprehensive Guide for Buyers

How Many Grades Are There?

There are four grades of solar panels, but only three of them are usable. Some manufacturers may expand upon this with pluses and minuses to show how individual solar panels rank, but this is rare.

The grading system goes A for the best, B for visually defective panels but meet performance benchmarks, C for visually and performatively defective solar panels, and D for broken solar panels.

Most manufacturers and distributors only sell grade A and B solar panels, scrapping C solar panels and recycling D solar panels. A’s are typically the most advertised and sold. However, some do sell grade B solar panels upon request.

Most factories keep grade B solar panels for testing as they can’t be sold at the same price as grade A panels but perform the same. However, overflow grade B panels are sold to the public.

How are Solar Panels Graded?

Grade A solar panels have no visual defects and meet performance specifications. These are the most popular solar panels and are sold at market value.

They typically come with manufacturer warranties and are the best solar panel for businesses and suburban homes as they provide ample power and look good.

Grade B solar panels have visual defects but meet performance specifications. These solar panels are less common than grade A solar panels but are typically available from manufacturers upon request.

Most manufacturers keep these panels for testing purposes but sell them with warranties like grade A solar panels.

Grade B solar panels typically fall under the market value and are sold at lower prices than grade A solar panels. If you need solar panels for a countryside barn or remote location, or they’ll be far from prying eyes, they are great for performance at a reasonable price.

Grade C solar panels have visual and performance defects, causing them to fall far behind in desirability. Grade C solar panels usually sold overseas at far lower prices in third-world countries.

Buying these solar panels is not worth it as they break down much faster and don’t make nearly as much power as grade As and Bs.

Most manufacturers sell Grade C solar panels overseas as they are qualified as hazardous materials, and it’s more profitable to sell them at a loss than pay the fees to dispose of them.

Grade D solar panels are entirely broken. Usually caused by a disastrous mistake in the manufacturing process, these solar panels do not work.

They’re traditionally scrapped or recycled by the manufacturers as there’s little else you can do with them.

Solar panels on a house roof fitted vertical and horizontal 1

Which Type of Solar Panel is Best For Home Use?

So, which type of solar panel suits your needs best? The performance and pleasant appearance of grade A solar panels? The ugly appearance, yet the excellent performance of the grade B solar panels? Or can you get a group of grade C solar panels entirely free?

Whatever type you are considering, each has its market and purpose.

Grade A

These are the gold standard in solar panels, all the high performance you expect with a great look to boot. These solar panels look great on roofs and businesses while generating power. If you’re in doubt, these solar panels are your safest bet.

Their performance and looks come hand-in-hand with a high price tag. There is a price to pay for quality, and it’s evident with this grade of solar panels. However, the adage “you get what you pay for” rings especially true for electricity-generating solar panels.

Grade A solar panels also come with manufacturer warranties, guaranteeing their quality and performance, letting you know the manufacturer’s confidence in their solar panels.

Grade B

Grade B solar panels look bad but are perfectly operational. Their defects are entirely visual, meeting all the performance specifications set by the manufacturer. If you only want performance out of your solar panels and don’t care about looks, you can save money by getting this grade solar panel.

Manufacturers often keep these solar panels for testing purposes but usually sell them upon request. Moreover, they sell them at a discount as their visual defects keep them from being sold at market value.

Manufacturers often have warranties on grade B solar panels, either the same length as grade A solar panels or a shorter length of time. Nevertheless, warranties show the manufacturer is confident in the quality of the product and is always something you should look for.

Grade B solar panels are best suited for places where performance, not visual appeal, matters. Remote locations, solar farms, rarely accessed rooftops are all great locations for these solar panels.

However, businesses and homeowners may want to spring for grade A panels, as the visual defects cause the grade B solar panels to look shabbier than their pricier counterparts.

Grade C

Grade C solar panels fall behind in both looks and performance. They look shabby, perform shabbily, and break down sooner than grade As and Bs. Manufacturers sell grade C solar panels at a loss to third-world countries to avoid the hazardous material fee. 

So under what circumstances would you buy grade C solar panels? Buying them in first-world countries is typically more expensive than grade B solar panels, as you have to pay to have them shipped from overseas.

The severe drop in the price of these solar panels puts them more in range of tighter budgets and lower wages. In addition, the main attraction of solar panels is that they can be set up anywhere to take advantage of the sun. This leaves buyers in third-world countries.

So these solar panels are mainly sold to areas without conventional power grids for locals to have some access to electricity. And while they don’t produce the same amount of power as grade As or Bs, there is a difference between having access to electricity and having none.

These solar panels help give power to struggling communities and narrow the energy and digital divide, making them perhaps the most essential grade of the solar panel.

Damaged solar panel cracked glass

Types of Defects

At the heart of the grading system are defects. These defects in solar panels are the basis for how they are graded, and knowing them can help you determine your grading stem for determining which grade solar panels fall into.

Keep in mind that most of these flaws are on a solar cell level, too small to be seen from afar. However, cells of similar grades are grouped to create solar panels.

Color Deviation

Color deviation is a purely visual flaw that causes the deep blue of the cell to turn yellow. This section of the cell doesn’t have the efficiency as the blue. However, it usually falls well within specifications.

Paste Leakage

Paste leakage is caused by the paste that lines the solar cells leaking out slightly, causing a small white dot to form along the lines, blocking a minimal surface area. Again this flaw is purely visual as the cell typically performs well with specifications.

Large Bend

A bend in the cell or panels is purely visual and doesn’t affect its performance. However, it does cause the sunlight to hit the panel differently, perhaps causing it to absorb less daylight, though not by much.

Chipped Cell

Chipped cells usually affect performance, as the breakage affects how power is gathered and flows. Manufacturers can salvage chipped cells by cutting off the chip or pasting the broken piece back on, meaning this flaw is at least salvageable.

Corner Breakage

When a corner is broken off of a cell, it affects the cell’s performance similarly to chips. However, Manufacturers can still salvage it as the broken piece can be cut off and the rest reused.

Missing Busbars

A missing busbar is a significant defect in solar cells that is both a visual and performance defect. It affects how power is generated in the cell, and you have to cut out a significant portion of the cell to reuse it.

Missing Print

Missing print on the front of the cell affects both its looks and performance, and most of the time, the cell cannot be salvaged. However, this cell is frequently used in grade C solar panels since it still performs.

Water Marks

Watermarks indicate water during the solar cell formation, which leaves both stains and altered chemical composition. While the damage done depends on the size of the watermark, this is typically a hallmark of grade C cells.

Depending on the position of the watermark, the cell could still be salvageable if manufacturers could cut out the watermark without compromising too much of the cell.


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Elliot has 20+ years of experience in renewable technology, from conservation to efficient living. His passion is to help others achieve independent off-grid living.

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