|The total market for flexible substrates will grow to US$1.2 bln by 2017, as per NanoMarkets. Demand for these materials is being driven by a wave of interest of adding flexibility in displays, solar panels and sensors as a way to expand markets in difficult times. Despite the considerable hype about flexible displays, much larger revenues for flexible substrate makers will come from the building-integrated PV (BIPV) sector. Substrates for flexible solar panels will account for US$536 mln in 2017. BIPV introduces a new architectural aesthetic and enables the costs of PV to be shared with the building fabric costs; flexible substrates will be a key enabling technology for these trends. Flexible solar panels will also be easier to transport and install. The earliest flexible substrates revenues will come from roll-to-roll (R2R) fabrication. R2R promises low-cost displays, lighting, RFID, etc. But there are still major challenges to be overcome in R2R since such processes often produce lower performance devices. These problems are expected to be resolved and the market for R2R flexible substrates will then explode. Meanwhile, the materials used for flexible substrates will change. The report predicts a major trend towards low-cost polymer substrates such as PET, as dramatic reductions in processing temperatures occur. This will also require more use of organic semiconductors. In addition, NanoMarkets sees flexible glass becoming a substantial market, if this material can support the same process technologies used for rigid glass displays. There will also be niche market for such novel flexible substrates as paper and textiles. Nonetheless, it is expected that the flexible substrates that are used to today will continue to take a significant share of the market. Metal substrates are already in widespread use (notably in the PV industry). Where strong, inert, cheap substrates are desired, stainless steel will remain a popular choice. Polyamide films are most likely to succeed in the long run where processing conditions are gentlest; printed PV would be an example here.
The high sensitivity to air and water vapor of thin-film PV (TFPV) is a factor that increasingly retards the market for this technology. TFPV got its big chance during the silicon shortage era, during which conventional crystalline silicon was held back by lack of availability of its main raw material. Now that the silicon shortage is over, there is a burden on the manufacturers of the newer forms of PV to find new ways to compete with c-Si modules. Newer forms of PV are often touted for their flexibility, but the fact is that today they consist overwhelmingly of fully glass-encapsulated modules. Rigid substrates also prevent new types of PV achieving cost advantages to the extent that they are barred from adopting R2R manufacturing processes. The apparently natural fit of TFPV for mobile PV and building integrated PV (BIPV) will also only be realized if more flexibility and higher performance encapsulation becomes possible. Nonetheless, flexible PV options have been slow to develop, in many cases primarily because flexible encapsulation options are considered cost prohibitive or technically inferior. As a result there seems to be opportunities for materials firms to come up with improved encapsulation and substrate options; ones that enable TFPV to better meet its promise.
In total, the TFPV substrate/encapsulation market is expected to reach US$1.3 bln by 2015, going on to reach US$1.8 bln by 2017. And while some of the most advanced encapsulation systems have proved difficult to develop and come with a high cost, several areas have been identified where these systems are beginning to make economic sense, most notably in the CIGS sector.