Canadian Solar CS6R 420W vs Maxeon Maxeon 6 AC 440W

Our Verdict Winner: Maxeon Maxeon 6 AC 440W

The Maxeon Maxeon 6 AC 440W wins this comparison by a decisive margin. It leads in efficiency (22.5% vs 21%) and matches or exceeds on warranty (25 vs 12 years). For most residential installations, the Maxeon Maxeon 6 AC 440W is the stronger choice.

Power / Capacity
420W
vs
440W
Efficiency
21%
vs
22.5%
Warranty
12 yrs
vs
25 yrs

Key Differences

  • Canadian Solar CS6R 420W is rated at 420W while Maxeon Maxeon 6 AC 440W is rated at 440W, a 20W difference.
  • Maxeon Maxeon 6 AC 440W achieves 22.5% efficiency vs 21% for the other, a 1.5 percentage point gap.
  • Maxeon Maxeon 6 AC 440W comes with a 25-year product warranty vs 12 years for the other.
  • Maxeon Maxeon 6 AC 440W has a superior temperature coefficient of -0.27%/°C vs -0.34%/°C, retaining more power in hot climates.
  • Canadian Solar CS6R 420W uses PERC Mono cells while Maxeon Maxeon 6 AC 440W uses IBC (Interdigitated Back Contact) cells, representing different technology generations.

Specifications Breakdown

Module Efficiency

The Maxeon Maxeon 6 AC 440W achieves 22.5% module efficiency compared to Canadian Solar CS6R 420W's 21%, meaning Maxeon Maxeon 6 AC 440W converts 1.5 percentage points more sunlight into electricity per square meter. In practical terms, the Canadian Solar CS6R 420W produces 215.1 watts per square meter of panel area while the Maxeon Maxeon 6 AC 440W produces 203.5 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 Maxeon Maxeon 6 AC 440W delivers 440W per panel versus 420W for the Canadian Solar CS6R 420W, a 20W difference per module. To build an 8 kW residential system, you would need 20 Canadian Solar CS6R 420W panels or 19 Maxeon Maxeon 6 AC 440W 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 Maxeon Maxeon 6 AC 440W has a temperature coefficient of -0.27%/°C versus -0.34%/°C for the Canadian Solar CS6R 420W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the Maxeon Maxeon 6 AC 440W retains 94.6% 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 Canadian Solar CS6R 420W is backed by a 12-year product warranty and 25-year performance guarantee, while the Maxeon Maxeon 6 AC 440W offers 25-year product and 25-year performance coverage. The Maxeon Maxeon 6 AC 440W provides 13 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 Canadian Solar CS6R 420W; 0.25% first year then 0.25%/year for Maxeon Maxeon 6 AC 440W), after 25 years the Canadian Solar CS6R 420W should retain approximately 86.5% of original output versus 93.8% for the Maxeon Maxeon 6 AC 440W. This 7.3 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.

Physical Dimensions & Weight

The Canadian Solar CS6R 420W measures 1722×1134×30mm and weighs 21 kg, while the Maxeon Maxeon 6 AC 440W measures 2067×1046×30mm at 22 kg. 1.95 m² of panel area for the Canadian Solar CS6R 420W versus 2.16 m² for the Maxeon Maxeon 6 AC 440W. Their weights are closely matched, so neither panel imposes a significantly different structural load on the mounting system. The more compact Canadian Solar CS6R 420W may be easier to fit on irregularly shaped or space-limited rooftops.

Specification Comparison

Specification Canadian Solar CS6R 420W Maxeon Maxeon 6 AC 440W
Power 420W 440W
Efficiency 21% 22.5%
Power Density 20.0 W/sq ft 18.9 W/sq ft
Cell Type PERC Mono IBC (Interdigitated Back Contact)
Bifacial No Yes
Weight 21 kg 22 kg
Temp Coefficient -0.34%/°C -0.27%/°C
Snow Load 5400 Pa 5400 Pa
Wind Load 2400 Pa 3600 Pa
Product Warranty 12 years 25 years
Performance Warranty 25 years 25 years
Degradation (Year 1) 1.5% 0.25%
Annual Degradation 0.5% 0.25%
Country China Malaysia

5-Dimension Head-to-Head Analysis

1. Efficiency & Power Density

Winner: Maxeon Maxeon 6 AC 440W

The Maxeon Maxeon 6 AC 440W achieves 22.5% efficiency versus 21% — a 1.5 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 0.6 kW more total system capacity, or 3 kWh more annual production in an average US location.

2. Hot Climate Performance

Winner: Maxeon Maxeon 6 AC 440W

The Maxeon Maxeon 6 AC 440W has a better temperature coefficient of -0.27%/°C versus -0.34%/°C. On a 45°C summer day (20°C above STC), the winner retains 94.6% of rated power versus 93.2%. This is a meaningful difference in hot states like Arizona, Texas, and Florida.

3. Durability & Warranty

Winner: Maxeon Maxeon 6 AC 440W

Maxeon Maxeon 6 AC 440W leads with a 25-year product warranty versus 12 years. Maxeon Maxeon 6 AC 440W degrades more slowly at 0.25% per year versus 0.5%. After 25 years, expect 86.5% vs 93.8% of original output for Canadian Solar CS6R 420W and Maxeon Maxeon 6 AC 440W respectively.

4. Power Output

Winner: Maxeon Maxeon 6 AC 440W

The Maxeon Maxeon 6 AC 440W delivers 440W versus 420W per panel — 20W more. For an 8 kW system, you need 19 panels with the higher-wattage option versus 20 panels, saving 1 panels and the associated racking and labor costs.

5. Cell Technology

Winner: Maxeon Maxeon 6 AC 440W

The Canadian Solar CS6R 420W uses PERC Mono: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. The Maxeon Maxeon 6 AC 440W uses IBC (Interdigitated Back Contact): IBC (Interdigitated Back Contact) moves all electrical contacts to the rear of the cell, maximizing front-side light capture for the highest possible efficiency. IBC (Interdigitated Back Contact) represents a newer generation technology with a longer performance runway as manufacturing matures.

Canadian Solar CS6R 420W

The CS6R is Canadian Solar's residential PERC workhorse delivering 420W in a compact, roof-friendly form factor.

Pros

  • + Compact residential size
  • + Affordable pricing
  • + Proven track record
  • + Easy installation

Cons

  • - Older PERC technology
  • - Standard performance
  • - Higher degradation
View full Canadian Solar CS6R 420W specs →

Maxeon Maxeon 6 AC 440W

The Maxeon 6 AC 440W is designed for commercial applications, delivering 440W with IBC technology in a commercial form factor with integrated microinverter option.

Pros

  • + IBC technology for commercial use
  • + Strong 22.5% efficiency
  • + Low degradation
  • + Excellent shade tolerance

Cons

  • - Commercial pricing
  • - Larger form factor
  • - Limited residential application
View full Maxeon Maxeon 6 AC 440W specs →

Choose Canadian Solar CS6R 420W If...

  • Budget residential installations from a bankable Tier 1 brand.

Choose Maxeon Maxeon 6 AC 440W 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 25+ years
  • 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

Our Recommendation

Recommended Maxeon Maxeon 6 AC 440W

The Maxeon Maxeon 6 AC 440W is the decisive winner in this solar panel comparison, outperforming the Canadian Solar CS6R 420W in 5 of 5 dimensions. Unless you have a specific requirement that the Canadian Solar CS6R 420W uniquely addresses, the Maxeon Maxeon 6 AC 440W is the stronger choice for virtually every installation scenario.

Frequently Asked Questions

Which is better, Canadian Solar CS6R 420W or Maxeon Maxeon 6 AC 440W?

The Maxeon Maxeon 6 AC 440W wins this comparison by a decisive margin. It leads in efficiency (22.5% vs 21%) and matches or exceeds on warranty (25 vs 12 years). For most residential installations, the Maxeon Maxeon 6 AC 440W is the stronger choice.

Which panel is more efficient, Canadian Solar CS6R 420W or Maxeon Maxeon 6 AC 440W?

The Maxeon Maxeon 6 AC 440W 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 1.5 percentage points translates to approximately 20W per panel under standard test conditions.

Which has a better warranty, Canadian Solar CS6R 420W or Maxeon Maxeon 6 AC 440W?

The Canadian Solar CS6R 420W comes with a 12-year product warranty and 25-year performance guarantee. The Maxeon Maxeon 6 AC 440W offers 25-year product and 25-year performance warranties. Maxeon Maxeon 6 AC 440W provides 13 additional years of product coverage.

Which panel performs better in hot weather?

The Canadian Solar CS6R 420W has a temperature coefficient of -0.34%/°C and the Maxeon Maxeon 6 AC 440W is -0.27%/°C. Maxeon Maxeon 6 AC 440W 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 CS6R 420W vs Maxeon Maxeon 6 AC 440W panels do I need for an 8 kW system?

For an 8 kW system: you need 20 Canadian Solar CS6R 420W panels (420W each) or 19 Maxeon Maxeon 6 AC 440W panels (440W each). The Maxeon Maxeon 6 AC 440W requires fewer panels, saving on racking hardware and installation labor.

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Last updated: February 2026