I get the sense that in the PV market at present, there is a growing appreciation for the quality of components of PV power plants. What is your take on the level of awareness amongst investors, developers and manufacturers about the importance of quality?
The awareness has reached the level of insurance companies and investors, who have a better understanding on that side than in previous years. There was a time when an understanding of what was quality was mainly restricted to those who built components themselves, but now there is a better technical understanding from those who actually buy them. So there are more questions as to what exactly a manufacturer does as well as what is done on project level.
How would you say those questions about quality are best answered then?
Third party certification is important, but as such, is not sufficient anymore. Investors want to know, ‘is a manufacturer able to maintain quality in a day-to-day production process.' A second question is also, ‘how is it assured that a lifetime assessment has been carried out.' And this second question doesn't mean a type approval but what a manufacturer is doing to show that its modules will last long enough in a certain climate.
Does this also apply to the financial standing of a manufacturer, which extends more the bankability area?
Bankability comprises several parts, and one would be the product bankability, where, e.g., extended stress tests and manufacturer audits come to play. The other one would be the company bankability — is the company insured well enough and is there a chance that it can maintain its position in the market?
Our organization doesn't get involved in these latter questions, but in companies' abilities to secure quality, while the financial power of a company is better judged by banks who know their business better than we do.
If you say certification alone is not sufficient to ensure quality for investors, do you think that quality of PV park components may in fact be declining?
It is true that certification alone is insufficient, but without it poor quality products would find their way onto the market easily. No I think the misconception has been, for a while now, that certification equals a lifetime testing. Certification is a ‘type approval' and ‘type approval' should ensure there are no design flaws so to eliminate the risk of early mortality, the risk that you have a false design. And of course it's comprised of tests that do simulate some environmental stresses that occur in nature. However, because nobody knows what exact environment the module that is built will end up in, you can't say IEC Certificate equals 1000 hours damp heat test equals twenty years life in Germany. That's just not possible because the diversity of technology is huge.
Another factor is that the experience of the industry is just not long enough. Of course there are modules in the market that have lasted 20 years, but they were built very differently than modules are today. So there is this factor of the lifetime correlation and a ‘type approval' can never give that.
What is the best way of providing lifetime assurances?
I think there is a need to implement a requirement for repetitive testing of modules in the market. That's something that's missing at the moment, market surveillance. At the moment manufacturers have their modules tested once and they have their certification via the standard.
Testing organizations have implemented — and we were the first, I think seven or eight years ago — factory inspections, which were not required by the standard. It means that the certification agent comes to the factory and sees if the quality control is good and the materials are actually the same as they were in the test samples. This is voluntary for the test agencies, but it's required for the test mark from TÜV Rheinland, for example. So the modules need not only to pass the test in the laboratory, but also pass the factory inspection repeatedly.
What I would expect is that there would be an improvement to have such inspections more frequently, maybe unannounced, and also to have some market surveillance testing — where modules are actually bought off the market. This, however, requires quality awareness and differentiation from minimum requirement certification.
Do the factory inspections that you're talking about also apply to the processes manufacturers employ and also their willingness to remedy certain processes if you find fault with them?
I can currently only speak for TÜV Rheinland, but when we carry out a factory inspection we check mainly three things. One is to look at materials to ensure that the correct ones are in stock and in use and they are not stored over their expiry date. We also look at processes, particularly, what is the lamination profile, for example, and to see whether that is maintained and that there are process records. The third one would be the quality control, to investigate what measures the manufacturer is taking to ensure this quality.
Also when we carry out one of these inspections it is always done by a PV expert who would make a deviation report that also includes recommendations. In follow up inspections, this expert would check whether the deviation as well as the recommendations have been ignored or implemented.
And how would you describe the level of uptake of ongoing factory inspection processes? How many manufacturers are open to it and ready and willing to open their doors?
It's a requirement for our test mark. What we don't have in our standard system and certification is a ranking system, so manufactures don't get a good or bad mark, they get a pass or fail. I know that some companies have asked us and others to do inspections additionally to the ones that are required by the certification processes and to produce an actual ranking.
We do have such reports that are voluntary or are requested by third party investors who would like someone like TÜV Rheinland to produce a ranking. They can then see on a ranking where a certain manufacturer is on quality control or on production or whatever. But this is not a pass of the certification scheme, which is assessed on a pass-fail basis.
Are their more players coming into the certification and inspection field now, as concerns and awareness about quality grows?
For the certification, not currently, there are actually players exiting the field. The entry of many new certification agencies in recent years, however, also led to a decrease in the value of certificates, as some of them posed only the minimum requirements. But for the due diligence services section, actually going to the factories and reporting on how well firms are set up for quality, yes there are a number of smaller new players.
What would your reaction be to suggestions that, with the more rapid growth in installations in the boom years of 2008 and 2009, that there may be large amounts of sub-standard components currently in PV power plants, in the field, from that time?
I fear that we will see the failures of that period coming soon. We've seen already after from the boom years in Spain that many of the power plants failed miserably after only one year or so into operation — not only because of the products, but a lot of it because of bad installation quality. More attention needs to be paid to installation quality. It's something that we're going to see more attention being paid to, we learned in Germany, particularly from times when we had these unplanned changes in FITs very rapidly. We had these rushes to install as many MW as possible in a very short time, by whatever person available could do it, trained or untrained.
How big a challenge will it be then, to remedy some of these installations — although I am aware this is not strictly your area of concern?
Actually it is partly our field, because we do not only do the product testing, but we also offer power plant services. We do yield assessments; either we do power plant inspections during the construction phase or as due diligence acceptance inspections while the plant is being set up, which is the best case because you can prevent the mistakes, make deviation reports and fix it. Or we are called to the power plant when it is too late and when there is a problem.
In this field though, there are many freelancers who do this job and do these assessments. On the side of the assessments however, there is no quality standard for quality assurance. There is also no standard level of training, one assessor or inspector might say that the the reason for a failure is one thing, while another might not even find this fault. With such diversity on the consultant side, it will be difficult to reach the required level of quality awareness, which is also a problem.
Would these additional quality assurances, of components and parks, add significant actual cost to the industry, at a time when the industry can't really afford higher costs?
What I was mentioning in the beginning was that to get a good view of quality in the market, you need good market surveillance and with that there would be an additional cost. What is happening is that investors and lenders do require additional test reports or additional extended tests — the double IEC as an example. But this is not a good situation because the requests are diverse and it becomes very complex. Everyone has a different opinion and there are so many different test methods.
I think it has come to the time when we need a conclusion as to what is the best test method and for me that requires taking products off the market for inspection. And that is after certification. First a ‘type approval' is needed to get in the market. But to have a market surveillance to buy products off the market and do some selective testing is important. These tests do not have to be too expensive as they may eliminate the need to do multiple tests for multiple investors. They can make sure that there is an acceptance in the market of quality but also to ensure the future of the Energiewende [energy transition], because if we have the experience that power plants fail miserably and the number of failures increase, then the industry as a whole will get bad press and there won't be acceptance of our technologies by the general public.
Jörg Althaus will be speaking at the Solarpraxis Quality for Photovoltaics conference on September 12, in Berlin, Germany.
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