Delamination of Solar Panels – A Threat to the Profitability of Solar Projects?

Categories: 2013 26 Jun 2013
Delamination of Solar Panels

Momentum Gruppen is involved in a matter concerning delamination of solar panels in a German solar park. The park has been in operation since 2010 and is performing very well – as a matter of fact the solar panels produce, in average, 20 % above the estimated budget.

A year ago some of the solar panels started to show signs of delamination. A later investigation shows that the delamination problem primarily lies within specific manufacturing series. The panels in question have been in operation in 3 years. So far there is no concluding evidence that states whether or not the production is lower because of the delamination. But is this a false security?

The concern is about whether the expected longevity of minimum 20 years is correct. If not, it will cause a great blow to the profitability of the solar project. Moreover, it is not conclusive whether or not it is to be expected that the production output will drop significantly on the panels that show signs of the delamination.

Many things point in the direction that the delamination is a symptom of sloppy fabrication work in China. In the years where the demand for solar panels was at its maximum the production went on too hasty.

In addition, the quality check has probably been too poor. Visible imprints from hands lies under the cover glass on many of the solar panels – in itself this is a major point of critique that should have been discovered through simple visual control. 

As the figure to the right shows, a solar panel consists of several layers. It becomes obvious that the process of putting the layers together, in some cases, have been carried out manually with a poor quality as a result.

Technically speaking this means that air and damp has been allowed to enter between the layers in the solar panels that should be hermetical tight. The symptoms of un-tight layers are large white stains (discoloration) under the cover glass. The white stains become larger and more propagated on the mentioned panels series during a period of time.

Momentum Gruppen has contacted an analysis institute that quality tests solar panels. The institute will run a 1.000 hours test to unveil if the affected panels are performing under the minimum standard and therefore should get replaced.

Since it is often several thousand panels that are involved in solar parks on +1 MW the potential replacement task is not uncomplicated. This is why Momentum Gruppen, as a first step, has initiated a random check of the last row of a total number of 3 in the solar park. Further, Momentum Gruppen has identified 3 different solar panel series that causes delamination problems. The purpose of the random check is to get solid knowledge on the extent of the delamination problem. Next step will be to put 1 of the delaminated solar panels through the earlier mentioned 1000 hour test. Only after these steps, the extent of the delamination problem can be fully established and  the initiatives to get the problem solved can be initiated.

In the worst case scenario the delamination will mean the replacement of 100s of solar panels a long time before expected causing a reduction of the expected return on investment.

In the best case scenario the delamination only appears in a small portion of the panels, which can be replaced ad hoc when the production drops to under the minimum standard. A solar panel equivalent to the affected solar panel series can be purchased for an amount of € 110 per panel incl. guarantee.

The production of solar panels in China went too fast at the time the panels in question were produced. According to an analysis made by Eternal Sun B. V. delamination is in the top three of the most observed quality problems for solar panels (source: This states the importance of monitoring the panels thoroughly and to interfere in good time as well as to contact the panel producer or the supplier if needed.

For Danish investors with investments in solar panels abroad it is important that the quality of the panels is checked. As a manager for Danish investors’ investments abroad it is natural for us to ensure that the assets function optimally.

For further information please contact CEO Kim Madsen on +45 46 33 70 10 or