Bifacial solar products light new pathway to future PV
As the PV market eagerly looks for new frontier innovations that could help maintain the current development trend, JinkoSolar shows that the average batch efficiency of biPERC cells is over 21.8%
Relatively few experimental and academic studies about bifacial p-type PERC cells have been published to date. This paper looks at the experimental findings from JinkoSolar’s large area, industry-grade bifacial monocrystalline silicon PERC (biPERC) cells. These cells are manufactured using mass production tools and in a continuous running condition.
The average batch efficiency of these biPERC cells is over 21.8%. Detailed analysis of the electrical parameters and cross sectional microscopic.
As the solar photovoltaic market and technology have improved over the past years, there has been an impressive drop in global PV electricity generation cost. One of the major contributors is the continuous increase in solar cell and module conversion efficiencies. For example, at JinkoSolar, average efficiency for p-type PERC solar cells has reached over 21.8%.
At the same time, concerns have also been raised that crystalline silicon PV products efficiencies are approaching a ceiling. As a result, the PV market is eagerly looking for new frontier innovations that could help maintain the current development trend. Bifacial solar cell technology and bifacial modules, which collect light energy from both the front and rear side of the panel can be this new frontier.
Bifacial cell and module technologies use most of the available panel surface area and effectively increase overall power generation efficiency.
JinkoSolar as one of the world’s largest solar module manufacturer has been at the forefront on the development of high-efficiency bifacial technologies.
P-type passivated emitter rear contact (PERC) is a mainstream high-efficiency solar cell technology, where a rear-side passivating dielectric layer is used to reduce the surface recombination power losses and to improve the internal reflection.
PERC technology has made huge strides in the market, and is an area where JinkoSolar has also invested in R&D efforts. JinkoSolar’s p-type PERC bifacial cell is based on our existing PERC structure. Localised rear contacts are formed through laser ablation on the passivation layer and subsequent screen-printing process.
Instead of full area Al contacts, Al fingers and busbars can be screen printed on the rear surface so that reflected light can also be absorbed for higher current output. PERC solar cells have the potential to achieve an average mass production efficiency of more than 22%.
Additionally, bifacial p-type PERC solar cells require less metal on the rear side and different processing recipes, enabling the potential for further future cost reduction.