Our first combined market survey on backsheets and encapsulation shows that leading manufacturers are active in both of these material segments that are key to protect a solar module for decades from the elements. The backsheet field continues to be dominated by two Chinese companies – Cybrid and Jolywood; in the encapsulation field it is one – Hangzhou First, followed by HIUV. While Chinese encapsulation market leader Hangzhou First also offers backsheet products, the global No. 1 in backsheets, Cybrid, has an encapsulation model in its portfolio as well as Crown, the third largest backsheet supplier in 2018.

A newcomer in the backsheet field, chemical company Borealis from Austria, is also addressing both segments backsheets and encapsulation.

Like with any other materials in wafer, cell and module processing, 2018 proved to be a very tough year for suppliers of backsheets and encapsulation products. After China’s 531 solar program restructuring announcement in May 2018, which led to dramatic module price drops, solar processing material sales prices got tremendously under pressure as well, which is having strong effects on market developments.

We are seeing the following major news and trends in the backsheets segment:

While fluoropolymer-based backsheets continued to dominate the market, demand moved even more towards lower-cost PVDF, which covered around 51% of the market last year. As PVDF prices are now close to non- fluoropolymer and coating-based products, it looks like PVDF will remain the leading backsheet material – and even increase its shares.

There are numerous materials and combinations for backsheets, however, the typical three-layer compound usually uses polymer-based polyester (PET) as the core, which has a proven track record and a good cost/ performance ratio. Now, Borealis is coming up with a solution to replace the PET core layer with something it says is cheaper and provides good quality but needs less material – a polypropylene based core solution from a major chemical company. If Borealis can really deliver on its promises, there is a good chance for them to break into the PET stronghold.

In fact, a few polypropylene based backsheets have been available in the past, but that was only as part of a complete backsheet product. Bischof + Klein (B+K) from Germany now comes with a full polypropylene solution – a core film and two protective layers. It is based on a low-cost co-extrusion process, which offers laminator companies to make the film on its own. With no fluorine content, the B+K product is promoted as 100% recyclable and environmentally friendly.

While polypropylene for the core is just being introduced and as a full backsheet solution also rather fresh, another new backsheet product has reached the stage that leading module manufacturers have been waiting for and are starting to use commercially – and that is transparent backsheets for solar’s hottest recent development, bifacial modules.

Clear backsheets have some advantages – among others weight, but basically every module manufacturer has been using glass for the backside of its bifacial modules so far. This was not a major problem for backsheets in the past, as bifacial’s share was rather small, but if the technology reaches a 30% share in 2021, as forecasted by ITRPV, this would be different. After DuPont introduced a new generation clear backsheet based on Tedlar last year, the world’s largest module manufacturer JinkoSolar has recently launched a bifacial module using a clear Tedlar- based backsheet – with a 30-year performance warranty. Such long warranties have been offered only for glass modules in the past (the ‘standard’ for glass-backsheet products is 25 years), which means

  1. backsheet makers are taking the glass-glass challenge seriously,
  2. DuPont and Jolywood are confident a Tedlar-based transparent backsheet can last 30 years.

Bifacial module technology is also on the mind of those backsheet companies active in the encapsulation segment. Interestingly, all of them listed in our survey offer polyolefin-based encapsulation products, which are almost exclusively used for glass-glass modules. That almost sounds like a back-up strategy in case glass-glass continues its success in the promising bifacial segment.

This article is the conclusions part of our first TaiyangNewsCombined Market Survey on Solar Backsheets & Encapsulation Materials, which was released in May 2019 and can be downloaded for free here.