First Solar Series 6 Plus 465W vs Renogy 450W Bifacial Mono Solar Panel
The Renogy 450W Bifacial Mono Solar Panel wins this comparison by a decisive margin. It leads in efficiency (22.8% vs 19.2%) and matches or exceeds on warranty (12 vs 10 years). For most residential installations, the Renogy 450W Bifacial Mono Solar Panel is the stronger choice.
Key Differences
- • First Solar Series 6 Plus 465W is rated at 465W while Renogy 450W Bifacial Mono Solar Panel is rated at 450W, a 15W difference.
- • Renogy 450W Bifacial Mono Solar Panel achieves 22.8% efficiency vs 19.2% for the other, a 3.6 percentage point gap.
- • Renogy 450W Bifacial Mono Solar Panel 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 -0.29%/°C, retaining more power in hot climates.
- • First Solar Series 6 Plus 465W uses CdTe (Cadmium Telluride) cells while Renogy 450W Bifacial Mono Solar Panel uses N-Type Monocrystalline cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
The Renogy 450W Bifacial Mono Solar Panel achieves 22.8% module efficiency compared to First Solar Series 6 Plus 465W's 19.2%, meaning Renogy 450W Bifacial Mono Solar Panel converts 3.6 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 Renogy 450W Bifacial Mono Solar Panel produces 233.1 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 First Solar Series 6 Plus 465W delivers 465W per panel versus 450W for the Renogy 450W Bifacial Mono Solar Panel, a 15W difference per module. To build an 8 kW residential system, you would need 18 First Solar Series 6 Plus 465W panels or 18 Renogy 450W Bifacial Mono Solar Panel 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 First Solar Series 6 Plus 465W has a temperature coefficient of -0.28%/°C versus -0.29%/°C for the Renogy 450W Bifacial Mono Solar Panel. 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 94.2%. 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 First Solar Series 6 Plus 465W is backed by a 10-year product warranty and 30-year performance guarantee, while the Renogy 450W Bifacial Mono Solar Panel offers 12-year product and 25-year performance coverage. The Renogy 450W Bifacial Mono Solar Panel 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% first year then 0.4%/year for Renogy 450W Bifacial Mono Solar Panel), after 25 years the First Solar Series 6 Plus 465W should retain approximately 86.5% of original output versus 89.4% for the Renogy 450W Bifacial Mono Solar Panel. This 2.9 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.
Physical Dimensions & Weight
The First Solar Series 6 Plus 465W measures 2009×1232×49mm and weighs 34.5 kg, while the Renogy 450W Bifacial Mono Solar Panel measures 1801×1072×30mm at 24.2 kg. 2.48 m² of panel area for the First Solar Series 6 Plus 465W versus 1.93 m² for the Renogy 450W Bifacial Mono Solar Panel. The Renogy 450W Bifacial Mono Solar Panel is 10.3 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 206 kg. The more compact Renogy 450W Bifacial Mono Solar Panel may be easier to fit on irregularly shaped or space-limited rooftops.
Specification Comparison
| Specification | First Solar Series 6 Plus 465W | Renogy 450W Bifacial Mono Solar Panel |
|---|---|---|
| Power | 465W | 450W |
| Efficiency | 19.2% | 22.8% |
| Power Density | 17.5 W/sq ft | 21.7 W/sq ft |
| Cell Type | CdTe (Cadmium Telluride) | N-Type Monocrystalline |
| Bifacial | No | Yes |
| Weight | 34.5 kg | 24.2 kg |
| Temp Coefficient | -0.28%/°C | -0.29%/°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% |
| Annual Degradation | 0.5% | 0.4% |
| Country | United States | China |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: Renogy 450W Bifacial Mono Solar PanelThe Renogy 450W Bifacial Mono Solar Panel achieves 22.8% efficiency versus 19.2% — a 3.6 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 465WThe First Solar Series 6 Plus 465W has a better temperature coefficient of -0.28%/°C versus -0.29%/°C. On a 45°C summer day (20°C above STC), the winner retains 94.4% of rated power versus 94.2%. The difference is modest but accumulates over 25 years of summer production.
3. Durability & Warranty
Winner: Renogy 450W Bifacial Mono Solar PanelRenogy 450W Bifacial Mono Solar Panel leads with a 12-year product warranty versus 10 years. Renogy 450W Bifacial Mono Solar Panel degrades more slowly at 0.4% per year versus 0.5%. After 25 years, expect 86.5% vs 89.4% of original output for First Solar Series 6 Plus 465W and Renogy 450W Bifacial Mono Solar Panel respectively.
4. Power Output
Winner: First Solar Series 6 Plus 465WThe First Solar Series 6 Plus 465W delivers 465W versus 450W per panel — 15W 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: TieThe First Solar Series 6 Plus 465W uses CdTe (Cadmium Telluride): CdTe (Cadmium Telluride). The Renogy 450W Bifacial Mono Solar Panel uses N-Type Monocrystalline: N-Type Monocrystalline. Both are equivalent-generation technologies.
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
Renogy 450W Bifacial Mono Solar Panel
The Renogy 450W Bifacial Mono Solar Panel is Renogy's flagship residential/commercial panel, combining N-Type monocrystalline cells with bifacial technology for up to 25% additional energy gain from reflected light.
Pros
- + Bifacial design with up to 25% energy gain
- + 22.8% efficiency with N-Type cells
- + 12-year product warranty — Renogy's longest
- + Good temperature coefficient at -0.29%/°C
- + UL 1703 certified for residential and commercial
Cons
- - 24.2 kg heavier than most residential panels
- - Bifacial gain requires proper mounting height and ground albedo
- - Higher upfront cost than monofacial alternatives
- - Large 1.93 m² footprint
Choose First Solar Series 6 Plus 465W If...
- ✓ You want fewer panels to reach your target system size, reducing racking and labor costs
- ✓ 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 Renogy 450W Bifacial Mono Solar Panel If...
- ✓ Your roof space is limited and you need maximum power per panel
- ✓ Long-term warranty protection is a top priority and you plan to stay in your home for 12+ years
- ✓ You want maximum output retention over the system's 25-30 year lifespan
- ✓ Residential and commercial installations seeking maximum energy harvest with bifacial gain, especially ground-mount systems.
Our Recommendation
The Renogy 450W Bifacial Mono Solar Panel is the decisive winner in this solar panel comparison, outperforming the First Solar Series 6 Plus 465W in 2 of 5 dimensions. Unless you have a specific requirement that the First Solar Series 6 Plus 465W uniquely addresses, the Renogy 450W Bifacial Mono Solar Panel is the stronger choice for virtually every installation scenario.
Frequently Asked Questions
Which is better, First Solar Series 6 Plus 465W or Renogy 450W Bifacial Mono Solar Panel?
The Renogy 450W Bifacial Mono Solar Panel wins this comparison by a decisive margin. It leads in efficiency (22.8% vs 19.2%) and matches or exceeds on warranty (12 vs 10 years). For most residential installations, the Renogy 450W Bifacial Mono Solar Panel is the stronger choice.
Which panel is more efficient, First Solar Series 6 Plus 465W or Renogy 450W Bifacial Mono Solar Panel?
The Renogy 450W Bifacial Mono Solar Panel at 22.8% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 3.6 percentage points translates to approximately 15W per panel under standard test conditions.
Which has a better warranty, First Solar Series 6 Plus 465W or Renogy 450W Bifacial Mono Solar Panel?
The First Solar Series 6 Plus 465W comes with a 10-year product warranty and 30-year performance guarantee. The Renogy 450W Bifacial Mono Solar Panel offers 12-year product and 25-year performance warranties. Renogy 450W Bifacial Mono Solar Panel 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 Renogy 450W Bifacial Mono Solar Panel is -0.29%/°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 Renogy 450W Bifacial Mono Solar Panel 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 18 Renogy 450W Bifacial Mono Solar Panel panels (450W each). The First Solar Series 6 Plus 465W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026