REC Alpha Pure-RX 470W vs First Solar Series 6 Plus 465W

Our Verdict Winner: REC Alpha Pure-RX 470W

The REC Alpha Pure-RX 470W wins this comparison by a decisive margin. It leads in efficiency (22.6% vs 19.2%) and matches or exceeds on warranty (25 vs 10 years). For most residential installations, the REC Alpha Pure-RX 470W is the stronger choice.

Power / Capacity
470W
vs
465W
Efficiency
22.6%
vs
19.2%
Warranty
25 yrs
vs
10 yrs

Key Differences

  • REC Alpha Pure-RX 470W is rated at 470W while First Solar Series 6 Plus 465W is rated at 465W, a 5W difference.
  • REC Alpha Pure-RX 470W achieves 22.6% efficiency vs 19.2% for the other, a 3.4 percentage point gap.
  • REC Alpha Pure-RX 470W comes with a 25-year product warranty vs 10 years for the other.
  • REC Alpha Pure-RX 470W has a superior temperature coefficient of -0.24%/°C vs -0.28%/°C, retaining more power in hot climates.
  • REC Alpha Pure-RX 470W uses HJT (Heterojunction) cells while First Solar Series 6 Plus 465W uses CdTe (Cadmium Telluride) cells, representing different technology generations.

Specifications Breakdown

Module Efficiency

The REC Alpha Pure-RX 470W achieves 22.6% module efficiency compared to First Solar Series 6 Plus 465W's 19.2%, meaning REC Alpha Pure-RX 470W converts 3.4 percentage points more sunlight into electricity per square meter. In practical terms, the REC Alpha Pure-RX 470W produces 225.7 watts per square meter of panel area while the First Solar Series 6 Plus 465W produces 187.9 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 REC Alpha Pure-RX 470W delivers 470W per panel versus 465W for the First Solar Series 6 Plus 465W, a 5W difference per module. To build an 8 kW residential system, you would need 18 REC Alpha Pure-RX 470W panels or 18 First Solar Series 6 Plus 465W panels. Despite the per-panel wattage difference, both require the same number of panels for this system size due to rounding. Higher wattage per panel is particularly valuable for commercial-scale installations where panel count directly impacts balance-of-system costs.

Temperature Coefficient

The REC Alpha Pure-RX 470W has a temperature coefficient of -0.24%/°C versus -0.28%/°C for the First Solar Series 6 Plus 465W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the REC Alpha Pure-RX 470W retains 95.2% of its rated power while the other retains 94.4%. 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 REC Alpha Pure-RX 470W is backed by a 25-year product warranty and 25-year performance guarantee, while the First Solar Series 6 Plus 465W offers 10-year product and 30-year performance coverage. The REC Alpha Pure-RX 470W provides 15 additional years of defect protection, covering manufacturing issues, material failures, and premature performance loss. Based on their published degradation rates (0.5% first year then 0.35%/year for REC Alpha Pure-RX 470W; 1.5% first year then 0.5%/year for First Solar Series 6 Plus 465W), after 25 years the REC Alpha Pure-RX 470W should retain approximately 91.1% of original output versus 86.5% for the First Solar Series 6 Plus 465W. This 4.6 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.

Physical Dimensions & Weight

The REC Alpha Pure-RX 470W measures 1728×1205×30mm and weighs 22.7 kg, while the First Solar Series 6 Plus 465W measures 2009×1232×49mm at 34.5 kg. 2.08 m² of panel area for the REC Alpha Pure-RX 470W versus 2.48 m² for the First Solar Series 6 Plus 465W. The REC Alpha Pure-RX 470W is 11.8 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 236 kg. The more compact REC Alpha Pure-RX 470W may be easier to fit on irregularly shaped or space-limited rooftops.

Specification Comparison

Specification REC Alpha Pure-RX 470W First Solar Series 6 Plus 465W
Power 470W 465W
Efficiency 22.6% 19.2%
Power Density 21.0 W/sq ft 17.5 W/sq ft
Cell Type HJT (Heterojunction) CdTe (Cadmium Telluride)
Bifacial Yes No
Weight 22.7 kg 34.5 kg
Temp Coefficient -0.24%/°C -0.28%/°C
Snow Load 5400 Pa 5400 Pa
Wind Load 3600 Pa 4000 Pa
Product Warranty 25 years 10 years
Performance Warranty 25 years 30 years
Degradation (Year 1) 0.5% 1.5%
Annual Degradation 0.35% 0.5%
Country Singapore United States

5-Dimension Head-to-Head Analysis

1. Efficiency & Power Density

Winner: REC Alpha Pure-RX 470W

The REC Alpha Pure-RX 470W achieves 22.6% efficiency versus 19.2% — a 3.4 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 0.1 kW more total system capacity, or 1 kWh more annual production in an average US location.

2. Hot Climate Performance

Winner: REC Alpha Pure-RX 470W

The REC Alpha Pure-RX 470W has a better temperature coefficient of -0.24%/°C versus -0.28%/°C. On a 45°C summer day (20°C above STC), the winner retains 95.2% of rated power versus 94.4%. The difference is modest but accumulates over 25 years of summer production.

3. Durability & Warranty

Winner: REC Alpha Pure-RX 470W

REC Alpha Pure-RX 470W leads with a 25-year product warranty versus 10 years. REC Alpha Pure-RX 470W degrades more slowly at 0.35% per year versus 0.5%. After 25 years, expect 91.1% vs 86.5% of original output for REC Alpha Pure-RX 470W and First Solar Series 6 Plus 465W respectively.

4. Power Output

Winner: REC Alpha Pure-RX 470W

The REC Alpha Pure-RX 470W delivers 470W versus 465W per panel — 5W more. For an 8 kW system, you need 18 panels with the higher-wattage option versus 18 panels, saving 0 panels and the associated racking and labor costs.

5. Cell Technology

Winner: REC Alpha Pure-RX 470W

The REC Alpha Pure-RX 470W 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. The First Solar Series 6 Plus 465W uses CdTe (Cadmium Telluride): CdTe (Cadmium Telluride). HJT (Heterojunction) represents a newer generation technology with a longer performance runway as manufacturing matures.

REC Alpha Pure-RX 470W

The REC Alpha Pure-RX features advanced HJT cells delivering 470W with an industry-leading 25-year product warranty and exceptional temperature performance. Performance warranty guarantees 92% at year 25.

Pros

  • + Industry-leading 25-year product warranty
  • + Excellent -0.24%/°C temp coefficient
  • + HJT technology for superior longevity
  • + Lead-free REC Pure soldering

Cons

  • - Premium pricing
  • - Limited production capacity
  • - Specialized dimensions
View full REC Alpha Pure-RX 470W specs →

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 →

Choose REC Alpha Pure-RX 470W 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

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

  • Large commercial and utility projects wanting proven US thin-film technology.

Our Recommendation

Recommended REC Alpha Pure-RX 470W

The REC Alpha Pure-RX 470W is the decisive winner in this solar panel comparison, outperforming the First Solar Series 6 Plus 465W in 5 of 5 dimensions. Unless you have a specific requirement that the First Solar Series 6 Plus 465W uniquely addresses, the REC Alpha Pure-RX 470W is the stronger choice for virtually every installation scenario.

Frequently Asked Questions

Which is better, REC Alpha Pure-RX 470W or First Solar Series 6 Plus 465W?

The REC Alpha Pure-RX 470W wins this comparison by a decisive margin. It leads in efficiency (22.6% vs 19.2%) and matches or exceeds on warranty (25 vs 10 years). For most residential installations, the REC Alpha Pure-RX 470W is the stronger choice.

Which panel is more efficient, REC Alpha Pure-RX 470W or First Solar Series 6 Plus 465W?

The REC Alpha Pure-RX 470W at 22.6% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 3.4 percentage points translates to approximately 5W per panel under standard test conditions.

Which has a better warranty, REC Alpha Pure-RX 470W or First Solar Series 6 Plus 465W?

The REC Alpha Pure-RX 470W comes with a 25-year product warranty and 25-year performance guarantee. The First Solar Series 6 Plus 465W offers 10-year product and 30-year performance warranties. REC Alpha Pure-RX 470W provides 15 additional years of product coverage.

Which panel performs better in hot weather?

The REC Alpha Pure-RX 470W has a temperature coefficient of -0.24%/°C and the First Solar Series 6 Plus 465W is -0.28%/°C. REC Alpha Pure-RX 470W retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.

How many REC Alpha Pure-RX 470W vs First Solar Series 6 Plus 465W panels do I need for an 8 kW system?

For an 8 kW system: you need 18 REC Alpha Pure-RX 470W panels (470W each) or 18 First Solar Series 6 Plus 465W panels (465W each). The REC Alpha Pure-RX 470W requires fewer panels, saving on racking hardware and installation labor.

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Last updated: February 2026