JinkoSolar, frontunner in solar energy bifacial technology modules

Driven by the rapid development of the solar technical and commercial landscape in recent years, JinkoSolar, a global leader in the solar industry, has utilized its technical leadership as a springboard to make jumps in the global industry.

It has also greatly strengthened the firm’s leadership position in terms of photovoltaic research and development with an advanced manufacturing process, faster mass production speeds, and better quality control than our peers.

These advantages have allowed JinkoSolar to reach unprecedented module shipment numbers. Through a commitment to R&D, state-of-theart manufacturing processes, and tight quality control, JinkoSolar has created the ideal production conditions for industry-leading cell and module innovation.

JinkoSolar’s ambition is to lead the way in technology. The company has been a frontrunner in the recent development of high-efficiency bifacial technology modules.

Efficacy of the solution PV module conversion efficiency is increasing continuously, at the same time c-Si cell efficiencies are approaching a ceiling.

Bifacial technology, which enables the absorption of light energy from both the front and rear sides of the panel, could be the new frontier to maintain the current development trend, thus effectively increasing the overall PV generator yield.

Jinko Solar P-type bifacial modules (Bi-PERC) can reach a bifaciality of over 80% in laboratory tests and above 70% in mass production. Field data show that the output power of bifacial PV module is significantly higher than single-face ones; STC total power can exceed 320 Wp or 380 Wp respectively in a 60-cell or 72-cell module. When installed in an optimized PV system design and in an environment with a white painted ground, the incremental power of bifacial modules can range as high as 30%. When paired with applicable tracking system, the power generation capacity of bifacial modules can be over 40% compared to conventional modules.

The double-glass structure in JinkoSolar’s bifacial products protects the panel from permeation of oxygen and moisture. This protection enables higher reliability, increasing outdoor operational lifecycle (up to 30 years) and use of Jinko’s bifacial products in solar farms even for applications or regions that are not suitable for traditional PV modules based on glass-backsheet laminate technology. Also its frameless design has been used to reduce the likelihood of developing  potential-induced degradation phenomena.

Additionally, compared to conventional modules, bifacial modules can endure test conditions 3 times more severe than standard tests; the dynamical load test for JinkoSolar bifacial PERC modules have shown outstanding performance results with minimized cell cracks; Damp-heat (DH) 3000 test has also shown excellent results with less than 5% degradation rate. Correspondingly, bifacial modules enable power density increased compared to single-face P-type, henceforth they enable saving BOS costs including land area.

Taking into consideration an additional power from the rear-side of the generator of about 30% with optimized PV system design, almost 40% land utilization could be saved, if compared to conventional PV plants based on mono-facial technology.

JinkoSolar’s P-type Bifacial technology is based on our current PERC ( Passivated-Emitter Rear Contact) cell technology, where a rear side passivating dielectric layer is used to decrease the surface recombination power losses and to increase the internal reflection of long-wavelength IR light. Localized rear contacts are formed through laser ablation on the passivation layer and subsequent screen-printing process. Instead of full-area Aluminum Back Surface Field, aluminum fingers and busbars are then screen-printed on the rear surface so that light can also be absorbed, hence boosting the current output. PERC modules are likely to accomplish an average front-face efficiency of >22% in mass production.

Furthermore, in order to create the bifacial module, the 2.5 mm ultra-thin patterned encapsulation glass is applied on both sides of the bifacial cells. The heat dissipates to the surrounding air more easily thanks to thinner glasses, when compared to conventional modules.

Equally, the pattern on the inner side of the glasses has been designed to scatter incident lights, efficiently increasing light trapping and decreasing solar-thermal conversion. Also based on the field test results, the Eagle Dual Module has a temperature coefficient of -0.38%/℃, lower than standard module (-0.41%/℃). The practical operating temperature is measured to be 1-3℃ lower than standard glass-backsheet modules, hence specifying that bifacial modules perform better in hot environment as thermal-related losses are mitigated.

Jinko Solar bi-PERC technology improves the module performance while keeping the margin price increase at a competitive level. In fact the enhanced production process does not involve drastic manufacturing lines’ adjustments therefore the incremental price is negligible when compared to the economic benefits brought by the additional energy production.

Moreover, Bi-facial P-type PERC solar cells require up to 80% less aluminum paste on the rear side up to a different processing guidelines, enabling the potential for further future cost reduction. In addition, the Eagle Dual module, utilizing double glasses encapsulation, provides a better reliability with 30-year linear power degradation guarantee. Thus the significant gain in lifetime power generation makes it a tremendously attractive product.

The enhanced PV module efficiency of JinkoSolar’s bifacial products, both p-type and n-type series, show that module technology upgrades can be achieved at a competitive cost,substantially leading to significant reductions in Levelized Cost of Electricity (LCOE).