LONGi Hi-MO X6 445W vs Silfab SIL-500-NX 500W
The Silfab SIL-500-NX 500W wins this comparison by a decisive margin. It delivers more power (500W vs 445W). For most residential installations, the Silfab SIL-500-NX 500W is the stronger choice.
Key Differences
- • LONGi Hi-MO X6 445W is rated at 445W while Silfab SIL-500-NX 500W is rated at 500W, a 55W difference.
- • LONGi Hi-MO X6 445W achieves 22% efficiency vs 21.8% for the other, a 0.2 percentage point gap.
- • Silfab SIL-500-NX 500W comes with a 25-year product warranty vs 12 years for the other.
Specifications Breakdown
Module Efficiency
The LONGi Hi-MO X6 445W achieves 22% module efficiency compared to Silfab SIL-500-NX 500W's 21.8%, meaning LONGi Hi-MO X6 445W converts 0.2 percentage points more sunlight into electricity per square meter. In practical terms, the LONGi Hi-MO X6 445W produces 227.9 watts per square meter of panel area while the Silfab SIL-500-NX 500W produces 210.6 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 Silfab SIL-500-NX 500W delivers 500W per panel versus 445W for the LONGi Hi-MO X6 445W, a 55W difference per module. To build an 8 kW residential system, you would need 18 LONGi Hi-MO X6 445W panels or 16 Silfab SIL-500-NX 500W panels. Choosing the higher-wattage option saves 2 panels, 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
Both panels share an identical temperature coefficient of -0.29%/°C, meaning they lose power at the same rate as cell temperature rises above the 25°C standard test baseline. At 65°C cell temperature, both retain 94.2% of rated power. Neither panel has a thermal performance advantage, which makes this specification a non-factor in the comparison.
Warranty Coverage
The LONGi Hi-MO X6 445W is backed by a 12-year product warranty and 25-year performance guarantee, while the Silfab SIL-500-NX 500W offers 25-year product and 30-year performance coverage. The Silfab SIL-500-NX 500W provides 13 additional years of defect protection, covering manufacturing issues, material failures, and premature performance loss. Based on their published degradation rates (1% first year then 0.4%/year for LONGi Hi-MO X6 445W; 1% first year then 0.4%/year for Silfab SIL-500-NX 500W), after 25 years the LONGi Hi-MO X6 445W should retain approximately 89.4% of original output versus 89.4% for the Silfab SIL-500-NX 500W. The end-of-life output levels are closely matched.
Physical Dimensions & Weight
The LONGi Hi-MO X6 445W measures 1722×1134×30mm and weighs 21.5 kg, while the Silfab SIL-500-NX 500W measures 2094×1134×30mm at 25.5 kg. 1.95 m² of panel area for the LONGi Hi-MO X6 445W versus 2.37 m² for the Silfab SIL-500-NX 500W. The LONGi Hi-MO X6 445W is 4.0 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 80 kg. The more compact LONGi Hi-MO X6 445W may be easier to fit on irregularly shaped or space-limited rooftops.
Specification Comparison
| Specification | LONGi Hi-MO X6 445W | Silfab SIL-500-NX 500W |
|---|---|---|
| Power | 445W | 500W |
| Efficiency | 22% | 21.8% |
| Power Density | 21.2 W/sq ft | 19.6 W/sq ft |
| Cell Type | TOPCon N-type | TOPCon N-type |
| Bifacial | Yes | No |
| Weight | 21.5 kg | 25.5 kg |
| Temp Coefficient | -0.29%/°C | -0.29%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 2400 Pa | 2400 Pa |
| Product Warranty | 12 years | 25 years |
| Performance Warranty | 25 years | 30 years |
| Degradation (Year 1) | 1% | 1% |
| Annual Degradation | 0.4% | 0.4% |
| Country | China | United States |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: LONGi Hi-MO X6 445WThe LONGi Hi-MO X6 445W achieves 22% efficiency versus 21.8% — a 0.2 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 1.6 kW more total system capacity, or 8 kWh more annual production in an average US location.
2. Hot Climate Performance
Winner: TieBoth panels share a temperature coefficient of -0.29%/°C — identical heat tolerance.
3. Durability & Warranty
Winner: Silfab SIL-500-NX 500WSilfab SIL-500-NX 500W leads with a 25-year product warranty versus 12 years. After 25 years, expect 89.4% vs 89.4% of original output for LONGi Hi-MO X6 445W and Silfab SIL-500-NX 500W respectively.
4. Power Output
Winner: Silfab SIL-500-NX 500WThe Silfab SIL-500-NX 500W delivers 500W versus 445W per panel — 55W more. For an 8 kW system, you need 16 panels with the higher-wattage option versus 18 panels, saving 2 panels and the associated racking and labor costs.
5. Cell Technology
Winner: TieBoth panels use TOPCon N-type cell technology. No technology advantage for either product.
LONGi Hi-MO X6 445W
The Hi-MO X6 is LONGi's TOPCon N-type line offering 445W in a compact format, well-suited for space-constrained residential rooftops.
Pros
- + Compact size for residential roofs
- + Good N-type TOPCon efficiency
- + Advanced technology
- + Budget-friendly
Cons
- - Lower wattage than larger models
- - Mid-range efficiency for N-type
- - Less suited for very large roofs
Silfab SIL-500-NX 500W
Silfab SIL-500-NX is a US-manufactured N-type TOPCon panel delivering 500W with domestic production benefits and a 25-year warranty.
Pros
- + Made in USA
- + 25-year product warranty
- + N-type TOPCon technology
- + Strong domestic support
Cons
- - Higher cost than imports
- - Moderate efficiency
- - Limited brand awareness
Choose LONGi Hi-MO X6 445W If...
- ✓ Your roof space is limited and you need maximum power per panel
- ✓ You prefer newer cell technology with a longer performance improvement runway
- ✓ Homeowners wanting N-type TOPCon technology in a compact residential format.
Choose Silfab SIL-500-NX 500W If...
- ✓ 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 prefer newer cell technology with a longer performance improvement runway
- ✓ Homeowners prioritizing US-made solar panels with strong domestic warranty.
Our Recommendation
The Silfab SIL-500-NX 500W is the decisive winner in this solar panel comparison, outperforming the LONGi Hi-MO X6 445W in 2 of 5 dimensions. Unless you have a specific requirement that the LONGi Hi-MO X6 445W uniquely addresses, the Silfab SIL-500-NX 500W is the stronger choice for virtually every installation scenario.
Frequently Asked Questions
Which is better, LONGi Hi-MO X6 445W or Silfab SIL-500-NX 500W?
The Silfab SIL-500-NX 500W wins this comparison by a decisive margin. It delivers more power (500W vs 445W). For most residential installations, the Silfab SIL-500-NX 500W is the stronger choice.
Which panel is more efficient, LONGi Hi-MO X6 445W or Silfab SIL-500-NX 500W?
The LONGi Hi-MO X6 445W at 22% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 0.2 percentage points translates to approximately 55W per panel under standard test conditions.
Which has a better warranty, LONGi Hi-MO X6 445W or Silfab SIL-500-NX 500W?
The LONGi Hi-MO X6 445W comes with a 12-year product warranty and 25-year performance guarantee. The Silfab SIL-500-NX 500W offers 25-year product and 30-year performance warranties. Silfab SIL-500-NX 500W provides 13 additional years of product coverage.
Which panel performs better in hot weather?
The LONGi Hi-MO X6 445W has a temperature coefficient of -0.29%/°C and the Silfab SIL-500-NX 500W is -0.29%/°C. Both handle heat equally. A lower (less negative) temperature coefficient is better.
How many LONGi Hi-MO X6 445W vs Silfab SIL-500-NX 500W panels do I need for an 8 kW system?
For an 8 kW system: you need 18 LONGi Hi-MO X6 445W panels (445W each) or 16 Silfab SIL-500-NX 500W panels (500W each). The Silfab SIL-500-NX 500W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026