Kiribati double glass module production customization

Another major change that is also incorporated for glass-glass modules is swapping EVA for polyolefins as an encapsulant. This is due to the free radicals produced during the cross-linking lamination process of EVA. While traditional backsheets are somewhat permeable to the free radicals, the double-glass module is not.

Recently several double-glass (also called glass–glass or dual-glass modules) c-Si PV modules have been launched on the market, many of them by major PV manufacturers. These modules use a sheet of tempered glass at the rear of the module instead of the conventional polymer-based backsheet. There are several reasons why this structure is appealing.

Glass-Glass module designs are an old technology that utilises a glass layer on the back of modules in place of traditional polymer backsheets. They were heavy and expensive allowing for the lighter polymer backsheets to gain the majority of the market share at the time.

Therefore. over a 30 year lifetime it can be expected to still operate at 85% of the nameplate capacity. The weight of glass-glass modules are still an issue, with current designs using 2 mm thick glass on each side for framed modules, the weight is about 22 kg, while 2.5 mm on each side will increase the module's weight to 23 kg.

Double-glass PV modules are emerging as a technology which can deliver excellent performance and excellent durability at a competitive cost. In this paper a glass–glass module technology that uses liquid silicone encapsulation is described. The combination of the glass–glass structure and silicone is shown to lead to exceptional durability.

The double-glass bifacial module in 2019 is going to spread its wing starting from the domestic market. Under the pressure of subsidy-free plant development, such modules will be widely applied to utility-scale PV plants and then to distributed PV projects.