Introduction
As the solar industry continues to evolve at a rapid pace, two advanced cell technologies have emerged as the clear successors to traditional PERC panels: TOPCon (Tunnel Oxide Passivated Contact) and HJT (Heterojunction Technology). Both promise higher efficiency, better temperature coefficients, and improved long-term performance — but which one is the right choice for your specific project?
At JUST SOLAR, we manufacture both TOPCon and HJT modules, giving us a unique perspective on the strengths and trade-offs of each technology.
What Is TOPCon Technology?
TOPCon adds an ultra-thin tunnel oxide layer and a doped polysilicon layer on the rear side of the cell, significantly reducing carrier recombination losses.
JUST SOLAR TOPCon Modules:
- Power Output: 600W / 640W / 730W
- Cell Efficiency: Up to 24.5%
- Temperature Coefficient: -0.30%/°C
- Bifaciality Factor: Up to 80%
Advantages of TOPCon:
- Cost-effective manufacturing — Can be produced on upgraded PERC production lines
- Proven supply chain — Wide availability of materials and equipment
- High bifaciality — Excellent performance in ground-mount systems
- Competitive pricing — Lower production costs, better $/W value
What Is HJT Technology?
HJT combines crystalline silicon with thin-film amorphous silicon layers, creating exceptional passivation on both surfaces of the wafer.
JUST SOLAR HJT Modules:
- Power Output: 730W
- Cell Efficiency: Up to 25.2%
- Temperature Coefficient: -0.26%/°C (industry-leading)
- Bifaciality Factor: Up to 85%
Advantages of HJT:
- Superior temperature performance — Best-in-class for hot climates
- Higher bifaciality — More power from reflected light
- Lower degradation — No LID concerns
- Simpler manufacturing — Fewer production steps
Head-to-Head Comparison
| Feature | TOPCon | HJT |
|---|---|---|
| Max Module Power | 730W | 730W |
| Cell Efficiency | ~24.5% | ~25.2% |
| Temperature Coefficient | -0.30%/°C | -0.26%/°C |
| Bifaciality | Up to 80% | Up to 85% |
| Best Climate | Temperate | Hot / Tropical |
| Price per Watt | Lower | Slightly Higher |
Which Technology Should You Choose?
Choose TOPCon If:
- Budget optimization is your top priority
- Your project is in a temperate climate (Europe, Northern China)
- You need proven, widely-available technology
- You’re building large utility-scale projects
Choose HJT If:
- Your project is in a hot climate (Middle East, Southeast Asia, Africa)
- Maximum energy yield per square meter is critical
- You want the lowest degradation rates over 30 years
- You’re building rooftop or space-constrained installations
Get a Quote from JUST SOLAR
As one of the few manufacturers offering both TOPCon and HJT modules at scale, we can help you select the optimal technology for your requirements.
- Email: sales@jusolar.com
- WhatsApp: +86 177 1730 3786
- Website: www.jusolar.com
