As solar cell conversion efficiency continues to improve, P-type solar cells are approaching the efficiency limit of 24.5%, and fail to completely solve the phenomenon of light decay generated by P-type silicon wafer-based cells, these factors make it difficult to have further development of P-type silicon cells. “The year 2022 is widely considered to be the first year of v”N-type” modules.
1.N-type components HJT, TOPCon technology
After the dividend of PV module power increase brought by the increase of silicon wafer size, the means to reduce the cost of kilowatt-hour returns to the fundamentals of cell module efficiency improvement brought by technology. n-type cells are based on the continuous pursuit of higher conversion efficiency, which will gradually begin to replace p-type cells, which is exactly the stage we are currently in.
2.N type vs P type with obvious advantages
Higher cell conversion efficiency
The minority carrier lifetime of N-type wafers is at least one order of magnitude higher than that of P-type wafers, which will greatly increase the open-circuit voltage and short-circuit current of the cell, resulting in higher cell conversion efficiency.
Lower power degradation
Greystone’s N-type module cell attenuation is low, with only about 60% of PERC’s annual attenuation, so customers can get more power generation. Compared with other brands of conventional mono-crystalline PERC solar panels, which only have a 25-year 80% power warranty, our N-type modules can ensure more than 90% power generation after 30 years.
Lower PID and LID degradation
N-type silicon wafers are mainly doped with phosphorus elements, which do not form boron-oxygen atom pairs in the material (i.e., the main cause of photogenic attenuation in P-type cells), so the initial light-induced attenuation LID and potential-induced attenuation PID of N-type modules are almost zero.
Low temperature coefficient
The temperature coefficient of N-type cells is low, and the power generation capacity increases. The output power of conventional P-type cells decreases by about 0.35%~0.45% for every degree of temperature increase, while the temperature coefficient of N-type cells is only about half of the former.
Better power generation in low light and high bifacial rate
N-type battery has good spectral response under low light conditions, and the bifacial battery can realize “dual-core power generation”, and the power generation can be increased by 20%-30% under suitable installation environment.
The backside power of ordinary mono-crystalline PERC bifacial modules is only 65% of that of the front side, while the backside of Greystone N-type modules can have 90% or more of the backside power, with higher power generation after bifacial stacking.