PV modules: Branding and bankability do not always correlate to quality

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To date, there have been no consumer reports on the quality or long-term reliability of photovoltaic products, so buying modules can be a dicey and pricey undertaking. Even a module that looks good to the average customer may have tiny defects in lamination or soldering that, over time in the field, will become microcracks or even overheat – requiring expensive repairs or full replacements.

That was the message conveyed by the management team of SolarBuyer LLC during a webinar on May 31, "Mitigating Widespread Module Risks with Innovative Procurement," sponsored by Boston-based GTM Research. The global procurement company, with offices in Berlin, Boston, Melbourne, and Shanghai, was founded by former solar manufacturing professionals who saw a gap on the purchasing side of the business and had the qualifications to fill it.

Large recalls

What they didn’t realize, but have rushed to resolve on behalf of their customers, was that industry certifications and Tier-1 classifications related to branding and bankability do not correlate to quality. Large recalls have been seen from Tier-1 manufacturers, including Renewable Energy Corp. (REC) in 2008, and First Solar in 2011 (See the June edition of pv magazine for a look at First Solar’s business).

In addition, although modules have reached the commercial stage of "commoditization," Ian Gregory, managing director of SolarBuyer LLC (USA), commented, "They are not all the same. There are multiple reasons for underperformance or failure, especially with the industry being in the downturn it is today. Manufacturers are beginning to take shortcuts, which have implications for quality and reliability."

Even more daunting is the fact that those shortcuts may elude attention because the solar supply chain is not transparent. "Right now," said Gregory, "it’s not clear to the buyer just where a module was manufactured, how it was made, or whether certified materials actually went into the production process."

What’s more, quality, itself, is extremely difficult to investigate and quantify. According to GTM senior analyst, Shyam Mehta, who moderated the webinar, "Quality is, quite frankly, outside the scope of market research and analysis."

Risk mitigation

With all these impediments, how can a purchaser mitigate the risks? Factory auditing and field inspections are essential, based on the experience of SolarBuyer. In fact, during the past five years, the firm has audited more than 30 major module manufacturers and independently inspected significant quantities of modules. Based on the results to date, defect rates in new modules range from five to 22 percent of products shipped.

Self-audits by manufacturers can provide additional information, but are not to be trusted as scrupulous appraisals. Customers should finance their own reviews, advised Gregory. "It’s quite common for manufacturers to pay for audits. We certainly don’t ignore those results, but sometimes we assess their findings alongside ours and find major discrepancies that could change the nature of the deal. In the end, it’s more cost-effective for customers to pay for auditing, themselves."

Continual updates also are essential. "The market is very dynamic," noted Gregory. "The top manufacturers of yesterday quite rapidly become questionable today, and manufacturers that struggled in the past can quickly become vendors of choice."

In addition, on-site inspections of purchased equipment, before it leaves the plant, reap benefits. Defective modules are never shipped; they are replaced at the source. The problems that contribute to module rejection are poor cell quality (in 38.6 percent of cases) and poor build quality (60.3 percent).

The worst is yet to come

Once the modules finally arrive, and are deployed to rooftops or ground-mounted, quality really comes into play. Field inspections help determine how the equipment is holding up to environmental stresses and continual operation. Premature failures or safety hazards, such as short circuits, can raise system costs significantly and reduce return on investment.

Unfortunately, the firm’s recent field inspections have found arrays that are fraught with problems. "Particularly in Europe, where deployments are the most mature, we are finding degradation of equipment, ranging from cell damage, to snail trails, to wind- or snow-related destruction, to burnouts, that could not have been predicted," said Kristina Loge, European sales manager for SolarBuyer, adding, "The science behind such defects is not well understood. Microcracks have appeared in the field in the last two years only."

In some areas, she stated, the worst is yet to come. "Some of the major problems in the field, in the younger markets, especially the United States, have not surfaced yet. Only time will tell, but the sustainability of the industry is at stake."

Loopholes

SolarBuyer believes that all of this attention to quality assurance (QA) will benefit its customers in three ways: integrating QA into procurement puts more onus on the manufacturer; applying QA during the buying process is cheaper than doing it afterward; and bundling QA for multiple buyers makes it cheaper for everyone.

By contrast, according to Peter Rusch, managing director (Europe), "Traditional risk mitigation is either expensive or questionable. Comprehensive insurance costs are high and the buyer usually must fight with the manufacturer over the validity of the claim. Warranties provide more loopholes than remuneration, and they often depend on the manufacturer’s continuing existence. Instead, proactive quality assurance can mitigate manufacturing risk, in many cases."

Finally, Rusch points out, risk is the manufacturer’s problem, but the customer must take responsibility for avoiding poor purchases. "Buyers need to push for stronger standards," he said, "but they also need strong advocates on their side, with experience in manufacturing and technical expertise. That’s why we come in, before and after the equipment goes out."

Edited by Becky Beetz.