Quality of solar panels: quantifying the difference between "cheap" and "good" ones

[mascip]

Hi, do cheap chinese solar panels really perform less well than better constructed panels? (and how would you identify these better constructed panels?)

I am curious about whether they lose efficiency quicker over the years. Are there any numbers out there to quantify this loss of power over the year?

Also, how would you go about measuring it, considering the scenario of solar panels on a boat, so you are rarely in the same location. Can the ageing and efficiency of the panels be measured by measuring the short-circuit current and open circuit voltage?

 

[SolarCity]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

Depends what you mean by 'cheap'. Any MCS certified Chinese solar panel is going to be a decent one. This idea that Chinese panels are of a lesser quality is no more than salesmen nonsense and outdated sinophobia.

 

[mascip]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

I'm guessing that I am not allowed to post a link to the actual website where I am thinking of buying the panels. The panels are second hand, model SESE48-156M, and it doesn't say that they are MCS certified (but it doesn't say that the "british manufactured A grade" ones are, either). They are sold for cheap because they were installed on a solar farm, half of which was damaged in a hail storm so the insurance company is paying to replace the whole installation. These panels have been tested by an independent laboratory, and I know people who bought them and they work well.

I am only worried about aging: will they still be as good as they are now, a few years down the line?

Shall I ask the seller whether they are MCS certified?

 

[SolarCity]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

If they were installed on a solar farm in the UK then they almost certainly are MCS certified. I'd say go for it. But be aware you won't be able to claim FIT payments from them.

 

[mascip]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

I am not planning to claim FIT payments, and I'm not sure where the solar farm was. I will ask the seller whether they are MCS certified. Thank you for this important piece of vocabulary

 

[Gavin A]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

I'd be a bit concerned about their statements about the snail trails.

 

[mascip]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

They say that the snail trails do not affect performance, and that each panel has been tested by an independent laboratory.

Obviously, I cannot test then before getting them. But it's a pretty reliable shop. I'm hoping they wouldn't make fake statements in fear or losing their good reputation.

But maybe I'm being too naive.

 

[meeb]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

I currently work as an asset manager with over 400MW of installs, and we have module defects across about 40% of our portfolio - which is ok as long as you pick it up during the acquisition phase! Symptoms such as snail trails may not immediately affect the generation but it is a sign that there is a inherent issue there; either the wafer is cracking or there is a chemical reaction between during the sealing process which has leaked, causing the snail trail.

Snail trails = bad/avoid!

Meeb

 

[Gavin A]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

I just did a comparison for a tender we just narrowly lost, and realised that not all salt mist certification is the same.

Futura Sun panels claim to have salt mist certification, but on investigating their warranty it seems that the warranty excludes any panels installed within 500m of the sea.

This tender being for a coastal location with a significant proportion of the panels within that exclusion zone, I'd be of the opinion that those panels are clearly inferior, and hopefully we've picked this issue up for this client before they end up with several roofs full of failing panels in a few years time.

 

[whinmoor]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

The pdf below talks about module degradation which might help to answer this question.

I'm pretty happy with the conclusion as we've got a fair few Phono Solar installations out there. I always thought they were a decent brand at a fair price.

We've got a couple on Solar Edge (due to mixed orientations) where you can see just how tight the tolerances are as adjacent panels are performing very similarly.

Sadly, Baywa & Waxman seem to have dropped them from their portfolios.

View attachment PV Module Reliability Scorecard.pdf

 

[The Solar King]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

I posted in the Green Lounge a link to an Australian Facebook page called crap solar. If we ever loose MCS certtification of panels, this is the kind of stuff that will be heading our way. It is also kept out by Minimum Import Pricing in the EU. as in all things, you will get what you pay for.

The bitterness of poor quality remains long after the sweet taste of low price is forgotten

 

[sgt_woulds]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

I know this is an old post but I thought I'd add my tuppence worth!

The MCS certification of panels is only a mild indication of quality at best, since they have don't have the slightest interest in policing and quality control. Once MCS has pocketed the money they don't give a damn!

The problem with a lot Chinese producers, and those 'European' or 'Canadian' manufacturers who just re-brand Chinese panels, is that they only care about producing a decent product up until the point where they have the certificate in their hands. After that it's pot luck.

Compare JA (brilliant) or Panasonic (beyond brilliant) to Renesolar (thieving lying scumbags) for a true example of good vs bad.

The trouble is you cannot always tell the quality just by looking at the panels. Renesolar all black panels look good from a distance - it's only when you take the panels apart and discover poly cells mixed with mono that you realise how bad it can get...

Oh and then that company pulls out of the UK and you get zero contact - and despite the fact that they are still MCS registered, MCS itself doesn't give a crap and offers no help.

Rant over.

What to look for:

Vertically integrated company who make the cells, assemble the panels, and sell them themselves.

Positive tolerance of panels. This can only really be seen with Solar Edge or micro inverters to allow comparisons. Not all positive tolerance panels are actually positive and it's down to the customer to catch them out.

If they've been trading less than 8 years run away.

If they don't have a UK rep run away

If they make a huge thing of their cell efficiency but hide their module efficiency in the small print run away

 

[LeeH]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

That's nice to now, I have 20 JA Percium panels on route.

 

[LeeH]

Re: Quality of solar panels: quantifying the difference between "cheap" and "good" on

Know...