Understanding the Two Leading High-Efficiency Solar Technologies
The solar industry is in the middle of a technology transition. While PERC panels dominated the last decade, two next-generation technologies are now battling for supremacy: HJT (Heterojunction with Intrinsic Thin-layer) and TOPCon (Tunnel Oxide Passivated Contact).
Both promise higher efficiency than PERC. Both are being adopted by major manufacturers. But they differ fundamentally in architecture, manufacturing complexity, real-world performance, and total cost of ownership.
How They Work
HJT - AGAIC BSM715
HJT combines crystalline silicon with thin-film amorphous silicon layers. AGAIC POWER BSM715 panels achieve 23.5% module efficiency with a temperature coefficient of just -0.26%/°C. The simpler manufacturing process (4 main steps) also means lower carbon footprint (<400 kgCO2/kW).
TOPCon
TOPCon uses an ultra-thin tunnel oxide layer for rear-side passivation. Most TOPCon cells retain the front-side emitter from PERC designs, making the upgrade path from existing factories easier. Efficiency reaches 22-23%.
Key Comparison
| Parameter | HJT (BSM715) | TOPCon |
|---|---|---|
| Efficiency | 22.5-23.5% | 22.0-23.0% |
| Temp Coefficient | -0.26%/°C | -0.30%/°C |
| Bifaciality | 90-95% | 80-85% |
| Carbon Footprint | <400 kgCO2/kW | ~500 kgCO2/kW |
| 25-Year Degradation | ~13% | ~15% |
Which to Choose?
Choose HJT if: hot climate, limited roof space, ground-mount bifacial, carbon-sensitive procurement.
Choose TOPCon if: upfront cost is primary constraint, moderate climate, flush roof mount.
AGAIC POWER Verdict
At AGAIC POWER, we invested in HJT because the physics favors it: fewer steps, lower temperature sensitivity, higher bifaciality, inherently lower degradation. Browse our BSM715 HJT solar panel series →
