Q CELLS Q.PEAK DUO BLK ML-G10+ 400W vs Tongwei THN-PE14M10 450W

Our Verdict Winner: Q CELLS Q.PEAK DUO BLK ML-G10+ 400W

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W wins this comparison by a decisive margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W is the stronger choice.

Power / Capacity
400W
vs
450W
Efficiency
20.9%
vs
21.5%
Warranty
25 yrs
vs
12 yrs

Key Differences

  • Q CELLS Q.PEAK DUO BLK ML-G10+ 400W is rated at 400W while Tongwei THN-PE14M10 450W is rated at 450W, a 50W difference.
  • Tongwei THN-PE14M10 450W achieves 21.5% efficiency vs 20.9% for the other, a 0.6 percentage point gap.
  • Q CELLS Q.PEAK DUO BLK ML-G10+ 400W comes with a 25-year product warranty vs 12 years for the other.

Specifications Breakdown

Module Efficiency

The Tongwei THN-PE14M10 450W achieves 21.5% module efficiency compared to Q CELLS Q.PEAK DUO BLK ML-G10+ 400W's 20.9%, meaning Tongwei THN-PE14M10 450W converts 0.6 percentage points more sunlight into electricity per square meter. In practical terms, the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W produces 204.8 watts per square meter of panel area while the Tongwei THN-PE14M10 450W produces 225.2 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 Tongwei THN-PE14M10 450W delivers 450W per panel versus 400W for the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W, a 50W difference per module. To build an 8 kW residential system, you would need 20 Q CELLS Q.PEAK DUO BLK ML-G10+ 400W panels or 18 Tongwei THN-PE14M10 450W 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

Both panels share an identical temperature coefficient of -0.34%/°C, meaning they lose power at the same rate as cell temperature rises above the 25°C standard test baseline. At 65°C cell temperature, both retain 93.2% of rated power. Neither panel has a thermal performance advantage, which makes this specification a non-factor in the comparison.

Warranty Coverage

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W is backed by a 25-year product warranty and 25-year performance guarantee, while the Tongwei THN-PE14M10 450W offers 12-year product and 25-year performance coverage. The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W provides 13 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 Q CELLS Q.PEAK DUO BLK ML-G10+ 400W; 1.5% first year then 0.5%/year for Tongwei THN-PE14M10 450W), after 25 years the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W should retain approximately 89.4% of original output versus 86.5% for the Tongwei THN-PE14M10 450W. This 2.9 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.

Physical Dimensions & Weight

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W measures 1722×1134×30mm and weighs 20.5 kg, while the Tongwei THN-PE14M10 450W measures 1762×1134×30mm at 23 kg. 1.95 m² of panel area for the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W versus 2.00 m² for the Tongwei THN-PE14M10 450W. The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W is 2.5 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 50 kg. Similar footprints mean both panels fit comparably on standard residential rooftop configurations.

Specification Comparison

Specification Q CELLS Q.PEAK DUO BLK ML-G10+ 400W Tongwei THN-PE14M10 450W
Power 400W 450W
Efficiency 20.9% 21.5%
Power Density 19.0 W/sq ft 20.9 W/sq ft
Cell Type PERC Mono PERC Mono
Bifacial No No
Weight 20.5 kg 23 kg
Temp Coefficient -0.34%/°C -0.34%/°C
Snow Load 5400 Pa 5400 Pa
Wind Load 3600 Pa 2400 Pa
Product Warranty 25 years 12 years
Performance Warranty 25 years 25 years
Degradation (Year 1) 1% 1.5%
Annual Degradation 0.4% 0.5%
Country South Korea China

5-Dimension Head-to-Head Analysis

1. Efficiency & Power Density

Winner: Tongwei THN-PE14M10 450W

The Tongwei THN-PE14M10 450W achieves 21.5% efficiency versus 20.9% — a 0.6 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 1.5 kW more total system capacity, or 7 kWh more annual production in an average US location.

2. Hot Climate Performance

Winner: Tie

Both panels share a temperature coefficient of -0.34%/°C — identical heat tolerance.

3. Durability & Warranty

Winner: Q CELLS Q.PEAK DUO BLK ML-G10+ 400W

Q CELLS Q.PEAK DUO BLK ML-G10+ 400W leads with a 25-year product warranty versus 12 years. Q CELLS Q.PEAK DUO BLK ML-G10+ 400W degrades more slowly at 0.4% per year versus 0.5%. After 25 years, expect 89.4% vs 86.5% of original output for Q CELLS Q.PEAK DUO BLK ML-G10+ 400W and Tongwei THN-PE14M10 450W respectively.

4. Power Output

Winner: Tongwei THN-PE14M10 450W

The Tongwei THN-PE14M10 450W delivers 450W versus 400W per panel — 50W more. For an 8 kW system, you need 18 panels with the higher-wattage option versus 20 panels, saving 2 panels and the associated racking and labor costs.

5. Cell Technology

Winner: Tie

Both panels use PERC Mono cell technology. No technology advantage for either product.

Q CELLS Q.PEAK DUO BLK ML-G10+ 400W

The Q.PEAK DUO BLK is a proven all-black PERC panel from Q CELLS, offering 400W with the same 25-year product warranty.

Pros

  • + 25-year product warranty
  • + All-black aesthetics
  • + Proven PERC reliability
  • + Widely available in US

Cons

  • - Lower efficiency than N-type
  • - Older technology
  • - Standard PERC degradation
View full Q CELLS Q.PEAK DUO BLK ML-G10+ 400W specs →

Tongwei THN-PE14M10 450W

Tongwei's THN-PE14M10 delivers 450W using proven PERC technology at a very competitive price point.

Pros

  • + Very competitive pricing
  • + Good output for size
  • + Strong cell technology
  • + Growing brand

Cons

  • - Less known outside China
  • - Standard warranty
  • - Limited US distribution
View full Tongwei THN-PE14M10 450W specs →

Choose Q CELLS Q.PEAK DUO BLK ML-G10+ 400W If...

  • Long-term warranty protection is a top priority and you plan to stay in your home for 25+ years
  • You want maximum output retention over the system's 25-30 year lifespan
  • Homeowners wanting an attractive, proven panel with extended warranty coverage.

Choose Tongwei THN-PE14M10 450W If...

  • Your roof space is limited and you need maximum power per panel
  • You want fewer panels to reach your target system size, reducing racking and labor costs
  • Value-focused projects seeking affordable panels from a major cell producer.

Our Recommendation

Recommended Q CELLS Q.PEAK DUO BLK ML-G10+ 400W

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W is the decisive winner in this solar panel comparison, outperforming the Tongwei THN-PE14M10 450W in 1 of 5 dimensions. Unless you have a specific requirement that the Tongwei THN-PE14M10 450W uniquely addresses, the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W is the stronger choice for virtually every installation scenario.

Frequently Asked Questions

Which is better, Q CELLS Q.PEAK DUO BLK ML-G10+ 400W or Tongwei THN-PE14M10 450W?

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W wins this comparison by a decisive margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W is the stronger choice.

Which panel is more efficient, Q CELLS Q.PEAK DUO BLK ML-G10+ 400W or Tongwei THN-PE14M10 450W?

The Tongwei THN-PE14M10 450W at 21.5% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 0.6 percentage points translates to approximately 50W per panel under standard test conditions.

Which has a better warranty, Q CELLS Q.PEAK DUO BLK ML-G10+ 400W or Tongwei THN-PE14M10 450W?

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W comes with a 25-year product warranty and 25-year performance guarantee. The Tongwei THN-PE14M10 450W offers 12-year product and 25-year performance warranties. Q CELLS Q.PEAK DUO BLK ML-G10+ 400W provides 13 additional years of product coverage.

Which panel performs better in hot weather?

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W has a temperature coefficient of -0.34%/°C and the Tongwei THN-PE14M10 450W is -0.34%/°C. Both handle heat equally. A lower (less negative) temperature coefficient is better.

How many Q CELLS Q.PEAK DUO BLK ML-G10+ 400W vs Tongwei THN-PE14M10 450W panels do I need for an 8 kW system?

For an 8 kW system: you need 20 Q CELLS Q.PEAK DUO BLK ML-G10+ 400W panels (400W each) or 18 Tongwei THN-PE14M10 450W panels (450W each). The Tongwei THN-PE14M10 450W requires fewer panels, saving on racking hardware and installation labor.

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Last updated: February 2026