First Solar Series 6 Plus 465W vs Hanwha Q.PEAK DUO XL-G11 480W

Our Verdict Winner: Hanwha Q.PEAK DUO XL-G11 480W

The Hanwha Q.PEAK DUO XL-G11 480W wins this comparison by a clear margin. It leads in efficiency (21.4% vs 19.2%) and matches or exceeds on warranty (12 vs 10 years). For most residential installations, the Hanwha Q.PEAK DUO XL-G11 480W is the stronger choice.

Power / Capacity
465W
vs
480W
Efficiency
19.2%
vs
21.4%
Warranty
10 yrs
vs
12 yrs

Key Differences

  • First Solar Series 6 Plus 465W is rated at 465W while Hanwha Q.PEAK DUO XL-G11 480W is rated at 480W, a 15W difference.
  • Hanwha Q.PEAK DUO XL-G11 480W achieves 21.4% efficiency vs 19.2% for the other, a 2.2 percentage point gap.
  • Hanwha Q.PEAK DUO XL-G11 480W comes with a 12-year product warranty vs 10 years for the other.
  • First Solar Series 6 Plus 465W has a superior temperature coefficient of -0.28%/°C vs -0.34%/°C, retaining more power in hot climates.
  • First Solar Series 6 Plus 465W uses CdTe (Cadmium Telluride) cells while Hanwha Q.PEAK DUO XL-G11 480W uses PERC Mono cells, representing different technology generations.

Specifications Breakdown

Module Efficiency

The Hanwha Q.PEAK DUO XL-G11 480W achieves 21.4% module efficiency compared to First Solar Series 6 Plus 465W's 19.2%, meaning Hanwha Q.PEAK DUO XL-G11 480W converts 2.2 percentage points more sunlight into electricity per square meter. In practical terms, the First Solar Series 6 Plus 465W produces 187.9 watts per square meter of panel area while the Hanwha Q.PEAK DUO XL-G11 480W produces 202.1 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 Hanwha Q.PEAK DUO XL-G11 480W delivers 480W per panel versus 465W for the First Solar Series 6 Plus 465W, a 15W difference per module. To build an 8 kW residential system, you would need 18 First Solar Series 6 Plus 465W panels or 17 Hanwha Q.PEAK DUO XL-G11 480W panels. Choosing the higher-wattage option saves 1 panel, 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 First Solar Series 6 Plus 465W has a temperature coefficient of -0.28%/°C versus -0.34%/°C for the Hanwha Q.PEAK DUO XL-G11 480W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the First Solar Series 6 Plus 465W retains 94.4% 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 First Solar Series 6 Plus 465W is backed by a 10-year product warranty and 30-year performance guarantee, while the Hanwha Q.PEAK DUO XL-G11 480W offers 12-year product and 25-year performance coverage. The Hanwha Q.PEAK DUO XL-G11 480W provides 2 additional years of defect protection, covering manufacturing issues, material failures, and premature performance loss. Based on their published degradation rates (1.5% first year then 0.5%/year for First Solar Series 6 Plus 465W; 1.5% first year then 0.5%/year for Hanwha Q.PEAK DUO XL-G11 480W), after 25 years the First Solar Series 6 Plus 465W should retain approximately 86.5% of original output versus 86.5% for the Hanwha Q.PEAK DUO XL-G11 480W. The end-of-life output levels are closely matched.

Physical Dimensions & Weight

The First Solar Series 6 Plus 465W measures 2009×1232×49mm and weighs 34.5 kg, while the Hanwha Q.PEAK DUO XL-G11 480W measures 2094×1134×35mm at 25.5 kg. 2.48 m² of panel area for the First Solar Series 6 Plus 465W versus 2.37 m² for the Hanwha Q.PEAK DUO XL-G11 480W. The Hanwha Q.PEAK DUO XL-G11 480W is 9.0 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 180 kg. The more compact Hanwha Q.PEAK DUO XL-G11 480W may be easier to fit on irregularly shaped or space-limited rooftops.

Specification Comparison

Specification First Solar Series 6 Plus 465W Hanwha Q.PEAK DUO XL-G11 480W
Power 465W 480W
Efficiency 19.2% 21.4%
Power Density 17.5 W/sq ft 18.8 W/sq ft
Cell Type CdTe (Cadmium Telluride) PERC Mono
Bifacial No No
Weight 34.5 kg 25.5 kg
Temp Coefficient -0.28%/°C -0.34%/°C
Snow Load 5400 Pa 5400 Pa
Wind Load 4000 Pa 2400 Pa
Product Warranty 10 years 12 years
Performance Warranty 30 years 25 years
Degradation (Year 1) 1.5% 1.5%
Annual Degradation 0.5% 0.5%
Country United States China

5-Dimension Head-to-Head Analysis

1. Efficiency & Power Density

Winner: Hanwha Q.PEAK DUO XL-G11 480W

The Hanwha Q.PEAK DUO XL-G11 480W achieves 21.4% efficiency versus 19.2% — a 2.2 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 0.5 kW more total system capacity, or 3 kWh more annual production in an average US location.

2. Hot Climate Performance

Winner: First Solar Series 6 Plus 465W

The First Solar Series 6 Plus 465W has a better temperature coefficient of -0.28%/°C versus -0.34%/°C. On a 45°C summer day (20°C above STC), the winner retains 94.4% of rated power versus 93.2%. This is a meaningful difference in hot states like Arizona, Texas, and Florida.

3. Durability & Warranty

Winner: Hanwha Q.PEAK DUO XL-G11 480W

Hanwha Q.PEAK DUO XL-G11 480W leads with a 12-year product warranty versus 10 years. After 25 years, expect 86.5% vs 86.5% of original output for First Solar Series 6 Plus 465W and Hanwha Q.PEAK DUO XL-G11 480W respectively.

4. Power Output

Winner: Hanwha Q.PEAK DUO XL-G11 480W

The Hanwha Q.PEAK DUO XL-G11 480W delivers 480W versus 465W per panel — 15W more. For an 8 kW system, you need 17 panels with the higher-wattage option versus 18 panels, saving 1 panels and the associated racking and labor costs.

5. Cell Technology

Winner: First Solar Series 6 Plus 465W

The First Solar Series 6 Plus 465W uses CdTe (Cadmium Telluride): CdTe (Cadmium Telluride). The Hanwha Q.PEAK DUO XL-G11 480W uses PERC Mono: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. CdTe (Cadmium Telluride) represents a newer generation technology with a longer performance runway as manufacturing matures.

First Solar Series 6 Plus 465W

The Series 6 Plus delivers 465W using First Solar's proven CdTe thin-film technology, manufactured in the United States.

Pros

  • + Proven US thin-film technology
  • + Excellent temperature coefficient
  • + Environmentally responsible
  • + Strong bankability

Cons

  • - Lower efficiency
  • - Very heavy panel
  • - Not suitable for residential
View full First Solar Series 6 Plus 465W specs →

Hanwha Q.PEAK DUO XL-G11 480W

Hanwha Q.PEAK DUO XL-G11 is a large-format PERC panel delivering 480W for commercial rooftop installations.

Pros

  • + Large format for commercial
  • + Good output per panel
  • + Proven technology
  • + Bankable manufacturer

Cons

  • - Standard PERC technology
  • - Large size
  • - Not for residential
View full Hanwha Q.PEAK DUO XL-G11 480W specs →

Choose First Solar Series 6 Plus 465W If...

  • You live in a hot climate (Arizona, Texas, Florida) where heat performance matters
  • Large commercial and utility projects wanting proven US thin-film technology.

Choose Hanwha Q.PEAK DUO XL-G11 480W 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
  • Long-term warranty protection is a top priority and you plan to stay in your home for 12+ years
  • Commercial rooftop installations seeking reliable large-format panels.

Our Recommendation

Recommended Hanwha Q.PEAK DUO XL-G11 480W

We recommend the Hanwha Q.PEAK DUO XL-G11 480W 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 First Solar Series 6 Plus 465W remains a good product, but the Hanwha Q.PEAK DUO XL-G11 480W delivers better overall value for the majority of installations.

Frequently Asked Questions

Which is better, First Solar Series 6 Plus 465W or Hanwha Q.PEAK DUO XL-G11 480W?

The Hanwha Q.PEAK DUO XL-G11 480W wins this comparison by a clear margin. It leads in efficiency (21.4% vs 19.2%) and matches or exceeds on warranty (12 vs 10 years). For most residential installations, the Hanwha Q.PEAK DUO XL-G11 480W is the stronger choice.

Which panel is more efficient, First Solar Series 6 Plus 465W or Hanwha Q.PEAK DUO XL-G11 480W?

The Hanwha Q.PEAK DUO XL-G11 480W at 21.4% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 2.2 percentage points translates to approximately 15W per panel under standard test conditions.

Which has a better warranty, First Solar Series 6 Plus 465W or Hanwha Q.PEAK DUO XL-G11 480W?

The First Solar Series 6 Plus 465W comes with a 10-year product warranty and 30-year performance guarantee. The Hanwha Q.PEAK DUO XL-G11 480W offers 12-year product and 25-year performance warranties. Hanwha Q.PEAK DUO XL-G11 480W provides 2 additional years of product coverage.

Which panel performs better in hot weather?

The First Solar Series 6 Plus 465W has a temperature coefficient of -0.28%/°C and the Hanwha Q.PEAK DUO XL-G11 480W is -0.34%/°C. First Solar Series 6 Plus 465W retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.

How many First Solar Series 6 Plus 465W vs Hanwha Q.PEAK DUO XL-G11 480W panels do I need for an 8 kW system?

For an 8 kW system: you need 18 First Solar Series 6 Plus 465W panels (465W each) or 17 Hanwha Q.PEAK DUO XL-G11 480W panels (480W each). The Hanwha Q.PEAK DUO XL-G11 480W requires fewer panels, saving on racking hardware and installation labor.

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Last updated: February 2026