Determining quality of solar panels 

Field tests data are restricted and takes years to assess performance over a long period of time. According to GTM Research, 85% of the global PV capacity has been installed in the past five years. This makes it challenging to examine what will happen in the next 15 to 25 years.

The TUV Rheinland released a study evaluating 2000 IEC certification tests performed during 10 years and still 10% of the tests led to failure. 
 

Globally established seal for photovoltaic modules quality

How do you define the quality of a panel? To ensure a product is of qualitative construction, we’re referred to a globally established seal for photovoltaic modules quality. This is the IEC 61215 certification for crystalline panels. The IEC certification is the outcome of commitment of the renewables industry for quality improvement.

To evaluate quality of panels, outdoor performance data must be utilized. As it is hard to wait for long periods, the concept was, from failures observed outdoors, to create accelerated stress tests that could recreate failures in a shorter period of time. This began in the mid 70’s at the NASA’s Jet Propulsion Lab (JPL) that created “five blocks buys” of accelerated stress tests from 1976 to 1981. Several different sets of modules were used. Tests were improved with the biggest leap forward.

Based on the success of JPL, the solar community, and the Research Center of the European Commission, creating more accurate testing tactics  led to the enforcement of the IEC 61215 in 1995. It’s second edition came out on 2005 that became the standard for the industry. Unfortunately, there are misunderstandings about IEC certifications and evaluating the quality of a solar module.

The IEC certification was initially developed to decrease infant mortality. John Wohlgemuth, from NREL discusses how a module that obtained the IEC 61215 certification should be considered: “passing the qualification test means the product has met a specific set of requirements. Those modules that have passed the qualification test are much more likely to survive in the field and not have design flaws that lead to infant mortality”. 
 

IEC 61215 doesn’t guarantee service lifetime

Surprisingly, this says very little about the behavior of panels in the 20-25 years time frame investors are taking into account. The IEC certification doesn’t state it’s ability of the product to fulfill guarantees. The evaluation of the long term behavior of solar modules is realistically at risk in this industry. Studies about the service lifetime of solar panels are few and far in between. The IEC 61215 is doesn’t guarantee the service lifetime of panels for the next 25 years.

If you want to find out what solar panels are right for you, go to HahaSmart.com and try our price checker tool. You can see how much you can save over the next 20 years by going solar, and we can help find local solar installers who can help. For more information relating to going solar, don't forget to visit our solar blog section for more handy guides and articles.