Canadian Solar BiHiKu7 670W vs Tongwei THN-EP08M10 580W
The Canadian Solar BiHiKu7 670W wins this comparison by a clear margin. It delivers more power (670W vs 580W). For most residential installations, the Canadian Solar BiHiKu7 670W is the stronger choice.
Key Differences
- • Canadian Solar BiHiKu7 670W is rated at 670W while Tongwei THN-EP08M10 580W is rated at 580W, a 90W difference.
- • Tongwei THN-EP08M10 580W achieves 22.5% efficiency vs 22.3% for the other, a 0.2 percentage point gap.
- • Canadian Solar BiHiKu7 670W comes with a 15-year product warranty vs 12 years for the other.
- • Canadian Solar BiHiKu7 670W has a superior temperature coefficient of -0.28%/°C vs -0.29%/°C, retaining more power in hot climates.
- • Canadian Solar BiHiKu7 670W uses TOPCon N-type Bifacial cells while Tongwei THN-EP08M10 580W uses TOPCon N-type cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
The Tongwei THN-EP08M10 580W achieves 22.5% module efficiency compared to Canadian Solar BiHiKu7 670W's 22.3%, meaning Tongwei THN-EP08M10 580W converts 0.2 percentage points more sunlight into electricity per square meter. In practical terms, the Canadian Solar BiHiKu7 670W produces 215.7 watts per square meter of panel area while the Tongwei THN-EP08M10 580W produces 224.5 W/m². For rooftop installations where space is limited, this efficiency gap determines how many kilowatts you can fit on your available roof area. Over a 25-year system life, even a small efficiency advantage compounds into meaningful additional energy production.
Power Output
The Canadian Solar BiHiKu7 670W delivers 670W per panel versus 580W for the Tongwei THN-EP08M10 580W, a 90W difference per module. To build an 8 kW residential system, you would need 12 Canadian Solar BiHiKu7 670W panels or 14 Tongwei THN-EP08M10 580W panels. Choosing the higher-wattage option saves 2 panels, reducing total racking hardware, wiring, and installation labor costs. Higher wattage per panel is particularly valuable for commercial-scale installations where panel count directly impacts balance-of-system costs.
Temperature Coefficient
The Canadian Solar BiHiKu7 670W has a temperature coefficient of -0.28%/°C versus -0.29%/°C for the Tongwei THN-EP08M10 580W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the Canadian Solar BiHiKu7 670W retains 94.4% of its rated power while the other retains 94.2%. While the numerical gap is modest, it still accumulates over decades of summer production, especially in southern latitudes with prolonged peak heat hours.
Warranty Coverage
The Canadian Solar BiHiKu7 670W is backed by a 15-year product warranty and 30-year performance guarantee, while the Tongwei THN-EP08M10 580W offers 12-year product and 25-year performance coverage. The Canadian Solar BiHiKu7 670W provides 3 additional years of defect protection, covering manufacturing issues, material failures, and premature performance loss. Based on their published degradation rates (1% first year then 0.4%/year for Canadian Solar BiHiKu7 670W; 1% first year then 0.4%/year for Tongwei THN-EP08M10 580W), after 25 years the Canadian Solar BiHiKu7 670W should retain approximately 89.4% of original output versus 89.4% for the Tongwei THN-EP08M10 580W. The end-of-life output levels are closely matched.
Physical Dimensions & Weight
The Canadian Solar BiHiKu7 670W measures 2384×1303×35mm and weighs 34.5 kg, while the Tongwei THN-EP08M10 580W measures 2278×1134×35mm at 28.5 kg. 3.11 m² of panel area for the Canadian Solar BiHiKu7 670W versus 2.58 m² for the Tongwei THN-EP08M10 580W. The Tongwei THN-EP08M10 580W is 6.0 kg lighter per panel, which reduces structural load requirements on the roof and makes handling easier during installation. For a 20-panel system, that is a total weight difference of 120 kg. The more compact Tongwei THN-EP08M10 580W may be easier to fit on irregularly shaped or space-limited rooftops.
Specification Comparison
| Specification | Canadian Solar BiHiKu7 670W | Tongwei THN-EP08M10 580W |
|---|---|---|
| Power | 670W | 580W |
| Efficiency | 22.3% | 22.5% |
| Power Density | 20.0 W/sq ft | 20.9 W/sq ft |
| Cell Type | TOPCon N-type Bifacial | TOPCon N-type |
| Bifacial | Yes | No |
| Weight | 34.5 kg | 28.5 kg |
| Temp Coefficient | -0.28%/°C | -0.29%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 2400 Pa | 2400 Pa |
| Product Warranty | 15 years | 12 years |
| Performance Warranty | 30 years | 25 years |
| Degradation (Year 1) | 1% | 1% |
| Annual Degradation | 0.4% | 0.4% |
| Country | China | China |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: Tongwei THN-EP08M10 580WThe Tongwei THN-EP08M10 580W achieves 22.5% efficiency versus 22.3% — a 0.2 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 2.7 kW more total system capacity, or 13 kWh more annual production in an average US location.
2. Hot Climate Performance
Winner: Canadian Solar BiHiKu7 670WThe Canadian Solar BiHiKu7 670W has a better temperature coefficient of -0.28%/°C versus -0.29%/°C. On a 45°C summer day (20°C above STC), the winner retains 94.4% of rated power versus 94.2%. The difference is modest but accumulates over 25 years of summer production.
3. Durability & Warranty
Winner: Canadian Solar BiHiKu7 670WCanadian Solar BiHiKu7 670W leads with a 15-year product warranty versus 12 years. After 25 years, expect 89.4% vs 89.4% of original output for Canadian Solar BiHiKu7 670W and Tongwei THN-EP08M10 580W respectively.
4. Power Output
Winner: Canadian Solar BiHiKu7 670WThe Canadian Solar BiHiKu7 670W delivers 670W versus 580W per panel — 90W more. For an 8 kW system, you need 12 panels with the higher-wattage option versus 14 panels, saving 2 panels and the associated racking and labor costs.
5. Cell Technology
Winner: TieThe Canadian Solar BiHiKu7 670W uses TOPCon N-type Bifacial: TOPCon (Tunnel Oxide Passivated Contact) adds a thin tunnel oxide layer to reduce recombination losses, achieving higher efficiency than PERC while being manufacturable on existing production lines. The Tongwei THN-EP08M10 580W uses TOPCon N-type: TOPCon (Tunnel Oxide Passivated Contact) adds a thin tunnel oxide layer to reduce recombination losses, achieving higher efficiency than PERC while being manufacturable on existing production lines. Both are equivalent-generation technologies.
Canadian Solar BiHiKu7 670W
The BiHiKu7 is Canadian Solar's most powerful bifacial module at 670W, designed for utility-scale and large commercial projects.
Pros
- + Highest wattage available
- + Bifacial energy gain
- + Excellent for tracking systems
- + Low LCOE
Cons
- - Extremely large panel
- - Not for residential roofs
- - Very heavy at 34.5 kg
Tongwei THN-EP08M10 580W
Tongwei THN-EP08M10 is a high-output N-type TOPCon panel from one of the world's largest solar cell manufacturers.
Pros
- + Top cell manufacturer
- + High 580W output
- + Competitive pricing
- + Strong R&D backing
Cons
- - Limited brand recognition outside China
- - Standard warranty
- - Newer to module market
Choose Canadian Solar BiHiKu7 670W If...
- ✓ You want fewer panels to reach your target system size, reducing racking and labor costs
- ✓ Long-term warranty protection is a top priority and you plan to stay in your home for 15+ years
- ✓ You live in a hot climate (Arizona, Texas, Florida) where heat performance matters
- ✓ You prefer newer cell technology with a longer performance improvement runway
- ✓ Utility-scale and large commercial ground-mount projects.
Choose Tongwei THN-EP08M10 580W If...
- ✓ Your roof space is limited and you need maximum power per panel
- ✓ You prefer newer cell technology with a longer performance improvement runway
- ✓ Large installations seeking competitive N-type pricing from a cell technology leader.
Our Recommendation
We recommend the Canadian Solar BiHiKu7 670W for most buyers in this comparison. It wins 3 of 5 key dimensions and offers a clear advantage in the metrics that matter most for a solar panel purchase. The Tongwei THN-EP08M10 580W remains a good product, but the Canadian Solar BiHiKu7 670W delivers better overall value for the majority of installations.
Frequently Asked Questions
Which is better, Canadian Solar BiHiKu7 670W or Tongwei THN-EP08M10 580W?
The Canadian Solar BiHiKu7 670W wins this comparison by a clear margin. It delivers more power (670W vs 580W). For most residential installations, the Canadian Solar BiHiKu7 670W is the stronger choice.
Which panel is more efficient, Canadian Solar BiHiKu7 670W or Tongwei THN-EP08M10 580W?
The Tongwei THN-EP08M10 580W at 22.5% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 0.2 percentage points translates to approximately 90W per panel under standard test conditions.
Which has a better warranty, Canadian Solar BiHiKu7 670W or Tongwei THN-EP08M10 580W?
The Canadian Solar BiHiKu7 670W comes with a 15-year product warranty and 30-year performance guarantee. The Tongwei THN-EP08M10 580W offers 12-year product and 25-year performance warranties. Canadian Solar BiHiKu7 670W provides 3 additional years of product coverage.
Which panel performs better in hot weather?
The Canadian Solar BiHiKu7 670W has a temperature coefficient of -0.28%/°C and the Tongwei THN-EP08M10 580W is -0.29%/°C. Canadian Solar BiHiKu7 670W retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.
How many Canadian Solar BiHiKu7 670W vs Tongwei THN-EP08M10 580W panels do I need for an 8 kW system?
For an 8 kW system: you need 12 Canadian Solar BiHiKu7 670W panels (670W each) or 14 Tongwei THN-EP08M10 580W panels (580W each). The Canadian Solar BiHiKu7 670W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026