LONGi Hi-MO 6 580W vs Q CELLS Q.PEAK DUO 370W
The LONGi Hi-MO 6 580W wins this comparison by a decisive margin. It leads in efficiency (22.3% vs 20.4%) and matches or exceeds on warranty (12 vs 12 years). For most residential installations, the LONGi Hi-MO 6 580W is the stronger choice.
Key Differences
- • LONGi Hi-MO 6 580W is rated at 580W while Q CELLS Q.PEAK DUO 370W is rated at 370W, a 210W difference.
- • LONGi Hi-MO 6 580W achieves 22.3% efficiency vs 20.4% for the other, a 1.9 percentage point gap.
- • Both carry matching 12-year product warranties.
- • LONGi Hi-MO 6 580W has a superior temperature coefficient of -0.34%/°C vs -0.35%/°C, retaining more power in hot climates.
- • LONGi Hi-MO 6 580W uses PERC Mono Half-cut cells while Q CELLS Q.PEAK DUO 370W uses PERC Mono cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
The LONGi Hi-MO 6 580W achieves 22.3% module efficiency compared to Q CELLS Q.PEAK DUO 370W's 20.4%, meaning LONGi Hi-MO 6 580W converts 1.9 percentage points more sunlight into electricity per square meter. In practical terms, the LONGi Hi-MO 6 580W produces 224.5 watts per square meter of panel area while the Q CELLS Q.PEAK DUO 370W produces 189.5 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 LONGi Hi-MO 6 580W delivers 580W per panel versus 370W for the Q CELLS Q.PEAK DUO 370W, a 210W difference per module. To build an 8 kW residential system, you would need 14 LONGi Hi-MO 6 580W panels or 22 Q CELLS Q.PEAK DUO 370W panels. Choosing the higher-wattage option saves 8 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
The LONGi Hi-MO 6 580W has a temperature coefficient of -0.34%/°C versus -0.35%/°C for the Q CELLS Q.PEAK DUO 370W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the LONGi Hi-MO 6 580W retains 93.2% of its rated power while the other retains 93.0%. 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 LONGi Hi-MO 6 580W is backed by a 12-year product warranty and 25-year performance guarantee, while the Q CELLS Q.PEAK DUO 370W offers 12-year product and 25-year performance coverage. Both offer identical product warranty duration. Based on their published degradation rates (1.5% first year then 0.5%/year for LONGi Hi-MO 6 580W; 1% first year then 0.4%/year for Q CELLS Q.PEAK DUO 370W), after 25 years the LONGi Hi-MO 6 580W should retain approximately 86.5% of original output versus 89.4% for the Q CELLS Q.PEAK DUO 370W. This 2.9 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.
Physical Dimensions & Weight
The LONGi Hi-MO 6 580W measures 2278×1134×35mm and weighs 28.4 kg, while the Q CELLS Q.PEAK DUO 370W measures 1722×1134×30mm at 19.5 kg. 2.58 m² of panel area for the LONGi Hi-MO 6 580W versus 1.95 m² for the Q CELLS Q.PEAK DUO 370W. The Q CELLS Q.PEAK DUO 370W is 8.9 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 178 kg. The more compact Q CELLS Q.PEAK DUO 370W may be easier to fit on irregularly shaped or space-limited rooftops.
Specification Comparison
| Specification | LONGi Hi-MO 6 580W | Q CELLS Q.PEAK DUO 370W |
|---|---|---|
| Power | 580W | 370W |
| Efficiency | 22.3% | 20.4% |
| Power Density | 20.9 W/sq ft | 17.6 W/sq ft |
| Cell Type | PERC Mono Half-cut | PERC Mono |
| Bifacial | No | No |
| Weight | 28.4 kg | 19.5 kg |
| Temp Coefficient | -0.34%/°C | -0.35%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 2400 Pa | 3600 Pa |
| Product Warranty | 12 years | 12 years |
| Performance Warranty | 25 years | 25 years |
| Degradation (Year 1) | 1.5% | 1% |
| Annual Degradation | 0.5% | 0.4% |
| Country | China | Malaysia |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: LONGi Hi-MO 6 580WThe LONGi Hi-MO 6 580W achieves 22.3% efficiency versus 20.4% — a 1.9 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 6.3 kW more total system capacity, or 29 kWh more annual production in an average US location.
2. Hot Climate Performance
Winner: LONGi Hi-MO 6 580WThe LONGi Hi-MO 6 580W has a better temperature coefficient of -0.34%/°C versus -0.35%/°C. On a 45°C summer day (20°C above STC), the winner retains 93.2% of rated power versus 93.0%. The difference is modest but accumulates over 25 years of summer production.
3. Durability & Warranty
Winner: Q CELLS Q.PEAK DUO 370WQ CELLS Q.PEAK DUO 370W degrades more slowly at 0.4% per year versus 0.5%. After 25 years, expect 86.5% vs 89.4% of original output for LONGi Hi-MO 6 580W and Q CELLS Q.PEAK DUO 370W respectively.
4. Power Output
Winner: LONGi Hi-MO 6 580WThe LONGi Hi-MO 6 580W delivers 580W versus 370W per panel — 210W more. For an 8 kW system, you need 14 panels with the higher-wattage option versus 22 panels, saving 8 panels and the associated racking and labor costs.
5. Cell Technology
Winner: TieThe LONGi Hi-MO 6 580W uses PERC Mono Half-cut: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. The Q CELLS Q.PEAK DUO 370W uses PERC Mono: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. Both are equivalent-generation technologies.
LONGi Hi-MO 6 580W
LONGi Hi-MO 6 is a high-performance PERC mono half-cut panel delivering 580W with 22.3% efficiency, ideal for residential and commercial rooftops.
Pros
- + High 22.3% efficiency
- + Proven PERC technology
- + Strong bifacial gain potential
- + Competitive pricing
Cons
- - Large physical size
- - Requires compatible racking
- - Limited US availability
Q CELLS Q.PEAK DUO 370W
The Q.PEAK DUO is an entry-level PERC panel from Q CELLS offering 370W with solid quality at a more accessible price point.
Pros
- + Q CELLS quality at lower cost
- + Lightweight design
- + Proven half-cut cell design
- + Available worldwide
Cons
- - Lower wattage
- - Standard PERC efficiency
- - Shorter product warranty
Choose LONGi Hi-MO 6 580W 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
- ✓ You live in a hot climate (Arizona, Texas, Florida) where heat performance matters
- ✓ Homeowners wanting high-output PERC performance at a competitive price.
Choose Q CELLS Q.PEAK DUO 370W If...
- ✓ You want maximum output retention over the system's 25-30 year lifespan
- ✓ Budget installations wanting Q CELLS quality at an entry-level price.
Our Recommendation
The LONGi Hi-MO 6 580W is the decisive winner in this solar panel comparison, outperforming the Q CELLS Q.PEAK DUO 370W in 3 of 5 dimensions. Unless you have a specific requirement that the Q CELLS Q.PEAK DUO 370W uniquely addresses, the LONGi Hi-MO 6 580W is the stronger choice for virtually every installation scenario.
Frequently Asked Questions
Which is better, LONGi Hi-MO 6 580W or Q CELLS Q.PEAK DUO 370W?
The LONGi Hi-MO 6 580W wins this comparison by a decisive margin. It leads in efficiency (22.3% vs 20.4%) and matches or exceeds on warranty (12 vs 12 years). For most residential installations, the LONGi Hi-MO 6 580W is the stronger choice.
Which panel is more efficient, LONGi Hi-MO 6 580W or Q CELLS Q.PEAK DUO 370W?
The LONGi Hi-MO 6 580W 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 1.9 percentage points translates to approximately 210W per panel under standard test conditions.
Which has a better warranty, LONGi Hi-MO 6 580W or Q CELLS Q.PEAK DUO 370W?
The LONGi Hi-MO 6 580W comes with a 12-year product warranty and 25-year performance guarantee. The Q CELLS Q.PEAK DUO 370W offers 12-year product and 25-year performance warranties. Both offer identical warranty terms.
Which panel performs better in hot weather?
The LONGi Hi-MO 6 580W has a temperature coefficient of -0.34%/°C and the Q CELLS Q.PEAK DUO 370W is -0.35%/°C. LONGi Hi-MO 6 580W retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.
How many LONGi Hi-MO 6 580W vs Q CELLS Q.PEAK DUO 370W panels do I need for an 8 kW system?
For an 8 kW system: you need 14 LONGi Hi-MO 6 580W panels (580W each) or 22 Q CELLS Q.PEAK DUO 370W panels (370W each). The LONGi Hi-MO 6 580W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026