Technology

TOPCon

Acronym for: Tunnel Oxide Passivated Contact

Summary

N-type solar cell technology with a tunneling oxide passivation layer that achieves 25-26% efficiency.

Detailed Explanation

TOPCon is the dominant next-generation N-type solar cell technology, rapidly replacing PERC as the mainstream choice in 2026. It adds a thin tunnel oxide layer and doped polysilicon rear contact to improve cell efficiency to 25-26%. Compared to PERC, TOPCon delivers 3-5% more power in the same module size, lower temperature coefficient (-0.30%/°C vs -0.35%/°C), slower degradation (0.4%/year vs 0.55%/year), and higher bifaciality factor (80-85% vs 70%). Most Chinese Tier-1 factories now produce TOPCon modules in 580-640W (commercial) and 700-730W (utility-scale) wattages.

TOPCon Module Manufacturers

5 companies

Further Reading

Deep-Dive Articles

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