Q CELLS Q.PEAK DUO BLK ML-G10+ 400W vs Panasonic EVPV400H

Our Verdict Winner: Panasonic EVPV400H

The Panasonic EVPV400H wins this comparison by a clear margin. It leads in efficiency (21.2% vs 20.9%) and matches or exceeds on warranty (25 vs 25 years). For most residential installations, the Panasonic EVPV400H is the stronger choice.

Power / Capacity
400W
vs
400W
Efficiency
20.9%
vs
21.2%
Warranty
25 yrs
vs
25 yrs

Key Differences

  • Both panels are rated at 400W, so the comparison comes down to efficiency, warranty, and technology.
  • Panasonic EVPV400H achieves 21.2% efficiency vs 20.9% for the other, a 0.3 percentage point gap.
  • Both carry matching 25-year product warranties.
  • Panasonic EVPV400H has a superior temperature coefficient of -0.26%/°C vs -0.34%/°C, retaining more power in hot climates.
  • Q CELLS Q.PEAK DUO BLK ML-G10+ 400W uses PERC Mono cells while Panasonic EVPV400H uses HJT (Heterojunction) cells, representing different technology generations.

Specifications Breakdown

Module Efficiency

The Panasonic EVPV400H achieves 21.2% module efficiency compared to Q CELLS Q.PEAK DUO BLK ML-G10+ 400W's 20.9%, meaning Panasonic EVPV400H converts 0.3 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 Panasonic EVPV400H produces 204.8 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

Both panels are rated at 400W under standard test conditions (STC), requiring 20 panels each to build an 8 kW system. With identical wattage ratings, the power output dimension is a draw and does not favor either panel. The real differentiators become efficiency density, temperature behavior, and long-term degradation rates which determine actual field performance beyond the nameplate rating.

Temperature Coefficient

The Panasonic EVPV400H has a temperature coefficient of -0.26%/°C versus -0.34%/°C for the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the Panasonic EVPV400H retains 94.8% of its rated power while the other retains 93.2%. This difference is particularly significant in hot climates such as the American Southwest, the Middle East, and Southeast Asia, where panels routinely operate 30-40°C above STC for several hours each day. Over the system lifetime, the cumulative energy advantage from a better temperature coefficient can amount to 2-4% of total production.

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 Panasonic EVPV400H offers 25-year product and 25-year performance coverage. Both offer identical product warranty duration. Based on their published degradation rates (1% first year then 0.4%/year for Q CELLS Q.PEAK DUO BLK ML-G10+ 400W; 0.5% first year then 0.35%/year for Panasonic EVPV400H), after 25 years the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W should retain approximately 89.4% of original output versus 91.1% for the Panasonic EVPV400H. This 1.7 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 Panasonic EVPV400H measures 1722×1134×30mm at 21 kg. 1.95 m² of panel area for the Q CELLS Q.PEAK DUO BLK ML-G10+ 400W versus 1.95 m² for the Panasonic EVPV400H. Their weights are closely matched, so neither panel imposes a significantly different structural load on the mounting system. Similar footprints mean both panels fit comparably on standard residential rooftop configurations.

Specification Comparison

Specification Q CELLS Q.PEAK DUO BLK ML-G10+ 400W Panasonic EVPV400H
Power 400W 400W
Efficiency 20.9% 21.2%
Power Density 19.0 W/sq ft 19.0 W/sq ft
Cell Type PERC Mono HJT (Heterojunction)
Bifacial No Yes
Weight 20.5 kg 21 kg
Temp Coefficient -0.34%/°C -0.26%/°C
Snow Load 5400 Pa 5400 Pa
Wind Load 3600 Pa 2400 Pa
Product Warranty 25 years 25 years
Performance Warranty 25 years 25 years
Degradation (Year 1) 1% 0.5%
Annual Degradation 0.4% 0.35%
Country South Korea Japan

5-Dimension Head-to-Head Analysis

1. Efficiency & Power Density

Winner: Panasonic EVPV400H

The Panasonic EVPV400H achieves 21.2% efficiency versus 20.9% — a 0.3 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 0.0 kW more total system capacity, or 0 kWh more annual production in an average US location.

2. Hot Climate Performance

Winner: Panasonic EVPV400H

The Panasonic EVPV400H has a better temperature coefficient of -0.26%/°C versus -0.34%/°C. On a 45°C summer day (20°C above STC), the winner retains 94.8% of rated power versus 93.2%. This is a meaningful difference in hot states like Arizona, Texas, and Florida.

3. Durability & Warranty

Winner: Panasonic EVPV400H

Panasonic EVPV400H degrades more slowly at 0.35% per year versus 0.4%. After 25 years, expect 89.4% vs 91.1% of original output for Q CELLS Q.PEAK DUO BLK ML-G10+ 400W and Panasonic EVPV400H respectively.

4. Power Output

Winner: Tie

Both panels deliver 400W — identical power output per panel. System cost per watt will be the deciding factor.

5. Cell Technology

Winner: Panasonic EVPV400H

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W uses PERC Mono: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. The Panasonic EVPV400H uses HJT (Heterojunction): HJT (Heterojunction) combines crystalline silicon with amorphous silicon layers, delivering the best temperature coefficient and bifacial gains, but at higher manufacturing cost. HJT (Heterojunction) represents a newer generation technology with a longer performance runway as manufacturing matures.

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 →

Panasonic EVPV400H

DISCONTINUED: Panasonic exited solar manufacturing in 2023. The EVPV400H was Panasonic's standard HJT residential panel, delivering 400W with the brand's signature quality and longevity.

Pros

  • + Panasonic reliability
  • + HJT advantages
  • + Solid 25-year warranty
  • + Good all-round performer

Cons

  • - DISCONTINUED - no longer manufactured
  • - No new units available
  • - No ongoing product support
View full Panasonic EVPV400H specs →

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

  • Homeowners wanting an attractive, proven panel with extended warranty coverage.

Choose Panasonic EVPV400H If...

  • Your roof space is limited and you need maximum power per panel
  • You live in a hot climate (Arizona, Texas, Florida) where heat performance matters
  • You want maximum output retention over the system's 25-30 year lifespan
  • You prefer newer cell technology with a longer performance improvement runway
  • No longer available for new installations.

Our Recommendation

Recommended Panasonic EVPV400H

We recommend the Panasonic EVPV400H for most buyers in this comparison. It wins 4 of 5 key dimensions and offers a clear advantage in the metrics that matter most for a solar panel purchase. The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W remains a good product, but the Panasonic EVPV400H delivers better overall value for the majority of installations.

Frequently Asked Questions

Which is better, Q CELLS Q.PEAK DUO BLK ML-G10+ 400W or Panasonic EVPV400H?

The Panasonic EVPV400H wins this comparison by a clear margin. It leads in efficiency (21.2% vs 20.9%) and matches or exceeds on warranty (25 vs 25 years). For most residential installations, the Panasonic EVPV400H is the stronger choice.

Which panel is more efficient, Q CELLS Q.PEAK DUO BLK ML-G10+ 400W or Panasonic EVPV400H?

The Panasonic EVPV400H at 21.2% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 0.3 percentage points translates to approximately 0W per panel under standard test conditions.

Which has a better warranty, Q CELLS Q.PEAK DUO BLK ML-G10+ 400W or Panasonic EVPV400H?

The Q CELLS Q.PEAK DUO BLK ML-G10+ 400W comes with a 25-year product warranty and 25-year performance guarantee. The Panasonic EVPV400H offers 25-year product and 25-year performance warranties. Both offer identical warranty terms.

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 Panasonic EVPV400H is -0.26%/°C. Panasonic EVPV400H retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.

How many Q CELLS Q.PEAK DUO BLK ML-G10+ 400W vs Panasonic EVPV400H 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 20 Panasonic EVPV400H panels (400W each). Both require the same number of panels.

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Last updated: February 2026