First Solar Series 6 Plus 465W vs LONGi Hi-MO X6 Max 470W
The LONGi Hi-MO X6 Max 470W wins this comparison by a decisive margin. It leads in efficiency (22.3% vs 19.2%) and matches or exceeds on warranty (15 vs 10 years). For most residential installations, the LONGi Hi-MO X6 Max 470W is the stronger choice.
Key Differences
- • First Solar Series 6 Plus 465W is rated at 465W while LONGi Hi-MO X6 Max 470W is rated at 470W, a 5W difference.
- • LONGi Hi-MO X6 Max 470W achieves 22.3% efficiency vs 19.2% for the other, a 3.1 percentage point gap.
- • LONGi Hi-MO X6 Max 470W comes with a 15-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 LONGi Hi-MO X6 Max 470W uses TOPCon N-type cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
The LONGi Hi-MO X6 Max 470W achieves 22.3% module efficiency compared to First Solar Series 6 Plus 465W's 19.2%, meaning LONGi Hi-MO X6 Max 470W converts 3.1 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 LONGi Hi-MO X6 Max 470W produces 235.2 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 LONGi Hi-MO X6 Max 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 First Solar Series 6 Plus 465W panels or 18 LONGi Hi-MO X6 Max 470W 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 LONGi Hi-MO X6 Max 470W. 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 LONGi Hi-MO X6 Max 470W offers 15-year product and 30-year performance coverage. The LONGi Hi-MO X6 Max 470W provides 5 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 LONGi Hi-MO X6 Max 470W), after 25 years the First Solar Series 6 Plus 465W should retain approximately 86.5% of original output versus 89.4% for the LONGi Hi-MO X6 Max 470W. 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 LONGi Hi-MO X6 Max 470W measures 1762×1134×30mm at 23.5 kg. 2.48 m² of panel area for the First Solar Series 6 Plus 465W versus 2.00 m² for the LONGi Hi-MO X6 Max 470W. The LONGi Hi-MO X6 Max 470W is 11.0 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 220 kg. The more compact LONGi Hi-MO X6 Max 470W may be easier to fit on irregularly shaped or space-limited rooftops.
Specification Comparison
| Specification | First Solar Series 6 Plus 465W | LONGi Hi-MO X6 Max 470W |
|---|---|---|
| Power | 465W | 470W |
| Efficiency | 19.2% | 22.3% |
| Power Density | 17.5 W/sq ft | 21.9 W/sq ft |
| Cell Type | CdTe (Cadmium Telluride) | TOPCon N-type |
| Bifacial | No | Yes |
| Weight | 34.5 kg | 23.5 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 | 15 years |
| Performance Warranty | 30 years | 30 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: LONGi Hi-MO X6 Max 470WThe LONGi Hi-MO X6 Max 470W achieves 22.3% efficiency versus 19.2% — a 3.1 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: 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: LONGi Hi-MO X6 Max 470WLONGi Hi-MO X6 Max 470W leads with a 15-year product warranty versus 10 years. LONGi Hi-MO X6 Max 470W 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 LONGi Hi-MO X6 Max 470W respectively.
4. Power Output
Winner: LONGi Hi-MO X6 Max 470WThe LONGi Hi-MO X6 Max 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: LONGi Hi-MO X6 Max 470WThe First Solar Series 6 Plus 465W uses CdTe (Cadmium Telluride): CdTe (Cadmium Telluride). The LONGi Hi-MO X6 Max 470W uses TOPCon N-type: TOPCon (Tunnel Oxide Passivated Contact) adds a thin tunnel oxide layer to reduce recombination losses, achieving higher efficiency than PERC while being manufacturable on existing production lines. TOPCon N-type 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
LONGi Hi-MO X6 Max 470W
The Hi-MO X6 Max delivers 470W in a mid-size format with N-type TOPCon technology, bridging the gap between compact and large panels.
Pros
- + Mid-size versatility
- + N-type TOPCon efficiency
- + Good power-to-size ratio
- + LONGi reliability
Cons
- - Mid-range pricing
- - Not the highest output
- - Standard warranty
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 LONGi Hi-MO X6 Max 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 15+ years
- ✓ You want maximum output retention over the system's 25-30 year lifespan
- ✓ You prefer newer cell technology with a longer performance improvement runway
Our Recommendation
The LONGi Hi-MO X6 Max 470W is the decisive winner in this solar panel comparison, outperforming the First Solar Series 6 Plus 465W in 4 of 5 dimensions. Unless you have a specific requirement that the First Solar Series 6 Plus 465W uniquely addresses, the LONGi Hi-MO X6 Max 470W is the stronger choice for virtually every installation scenario.
Frequently Asked Questions
Which is better, First Solar Series 6 Plus 465W or LONGi Hi-MO X6 Max 470W?
The LONGi Hi-MO X6 Max 470W wins this comparison by a decisive margin. It leads in efficiency (22.3% vs 19.2%) and matches or exceeds on warranty (15 vs 10 years). For most residential installations, the LONGi Hi-MO X6 Max 470W is the stronger choice.
Which panel is more efficient, First Solar Series 6 Plus 465W or LONGi Hi-MO X6 Max 470W?
The LONGi Hi-MO X6 Max 470W at 22.3% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 3.1 percentage points translates to approximately 5W per panel under standard test conditions.
Which has a better warranty, First Solar Series 6 Plus 465W or LONGi Hi-MO X6 Max 470W?
The First Solar Series 6 Plus 465W comes with a 10-year product warranty and 30-year performance guarantee. The LONGi Hi-MO X6 Max 470W offers 15-year product and 30-year performance warranties. LONGi Hi-MO X6 Max 470W provides 5 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 LONGi Hi-MO X6 Max 470W 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 LONGi Hi-MO X6 Max 470W 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 LONGi Hi-MO X6 Max 470W panels (470W each). The LONGi Hi-MO X6 Max 470W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026