LONGi Hi-MO 7 620W vs LONGi Hi-MO X6 Max 470W
The LONGi Hi-MO 7 620W wins this comparison by a narrow margin. It leads in efficiency (23% vs 22.3%). For most residential installations, the LONGi Hi-MO 7 620W is the stronger choice.
Key Differences
- • LONGi Hi-MO 7 620W is rated at 620W while LONGi Hi-MO X6 Max 470W is rated at 470W, a 150W difference.
- • LONGi Hi-MO 7 620W achieves 23% efficiency vs 22.3% for the other, a 0.7 percentage point gap.
- • LONGi Hi-MO X6 Max 470W comes with a 15-year product warranty vs 12 years for the other.
- • LONGi Hi-MO 7 620W has a superior temperature coefficient of -0.28%/°C vs -0.29%/°C, retaining more power in hot climates.
- • LONGi Hi-MO 7 620W uses HPBC (Back Contact N-type) 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 7 620W achieves 23% module efficiency compared to LONGi Hi-MO X6 Max 470W's 22.3%, meaning LONGi Hi-MO 7 620W converts 0.7 percentage points more sunlight into electricity per square meter. In practical terms, the LONGi Hi-MO 7 620W produces 229.3 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 7 620W delivers 620W per panel versus 470W for the LONGi Hi-MO X6 Max 470W, a 150W difference per module. To build an 8 kW residential system, you would need 13 LONGi Hi-MO 7 620W panels or 18 LONGi Hi-MO X6 Max 470W panels. Choosing the higher-wattage option saves 5 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 7 620W 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 LONGi Hi-MO 7 620W 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 LONGi Hi-MO 7 620W is backed by a 12-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 3 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 LONGi Hi-MO 7 620W; 1% first year then 0.4%/year for LONGi Hi-MO X6 Max 470W), after 25 years the LONGi Hi-MO 7 620W should retain approximately 91.1% of original output versus 89.4% for the LONGi Hi-MO X6 Max 470W. This 1.7 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.
Physical Dimensions & Weight
The LONGi Hi-MO 7 620W measures 2384×1134×35mm and weighs 31 kg, while the LONGi Hi-MO X6 Max 470W measures 1762×1134×30mm at 23.5 kg. 2.70 m² of panel area for the LONGi Hi-MO 7 620W versus 2.00 m² for the LONGi Hi-MO X6 Max 470W. The LONGi Hi-MO X6 Max 470W is 7.5 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 150 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 | LONGi Hi-MO 7 620W | LONGi Hi-MO X6 Max 470W |
|---|---|---|
| Power | 620W | 470W |
| Efficiency | 23% | 22.3% |
| Power Density | 21.3 W/sq ft | 21.9 W/sq ft |
| Cell Type | HPBC (Back Contact N-type) | TOPCon N-type |
| Bifacial | Yes | Yes |
| Weight | 31 kg | 23.5 kg |
| Temp Coefficient | -0.28%/°C | -0.29%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 2400 Pa | 2400 Pa |
| Product Warranty | 12 years | 15 years |
| Performance Warranty | 30 years | 30 years |
| Degradation (Year 1) | 0.5% | 1% |
| Annual Degradation | 0.35% | 0.4% |
| Country | China | China |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: LONGi Hi-MO 7 620WThe LONGi Hi-MO 7 620W achieves 23% efficiency versus 22.3% — a 0.7 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 4.5 kW more total system capacity, or 21 kWh more annual production in an average US location.
2. Hot Climate Performance
Winner: LONGi Hi-MO 7 620WThe LONGi Hi-MO 7 620W 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 12 years. LONGi Hi-MO 7 620W degrades more slowly at 0.35% per year versus 0.4%. After 25 years, expect 91.1% vs 89.4% of original output for LONGi Hi-MO 7 620W and LONGi Hi-MO X6 Max 470W respectively.
4. Power Output
Winner: LONGi Hi-MO 7 620WThe LONGi Hi-MO 7 620W delivers 620W versus 470W per panel — 150W more. For an 8 kW system, you need 13 panels with the higher-wattage option versus 18 panels, saving 5 panels and the associated racking and labor costs.
5. Cell Technology
Winner: LONGi Hi-MO 7 620WThe LONGi Hi-MO 7 620W uses HPBC (Back Contact N-type): HPBC (Hybrid Passivated Back Contact) is a proprietary LONGi architecture combining back-contact design with advanced passivation for both high efficiency and aesthetic uniformity. 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. HPBC (Back Contact N-type) represents a newer generation technology with a longer performance runway as manufacturing matures.
LONGi Hi-MO 7 620W
The Hi-MO 7 620W is LONGi's highest-output panel using proprietary HPBC (Hybrid Passivated Back Contact) technology for exceptional efficiency. Newer LR7/LR8 variants support 620W+ output.
Pros
- + Highest LONGi output
- + HPBC cutting-edge back-contact technology
- + 23.0% efficiency
- + Excellent degradation profile
Cons
- - Very large form factor
- - Premium pricing
- - New technology
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 LONGi Hi-MO 7 620W 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
- ✓ You want maximum output retention over the system's 25-30 year lifespan
- ✓ Large installations wanting LONGi's most advanced HPBC technology.
Choose LONGi Hi-MO X6 Max 470W If...
- ✓ Long-term warranty protection is a top priority and you plan to stay in your home for 15+ years
- ✓ You prefer newer cell technology with a longer performance improvement runway
- ✓ Medium-sized residential roofs wanting a balance of size and N-type performance.
Our Recommendation
Both the LONGi Hi-MO 7 620W and LONGi Hi-MO X6 Max 470W are excellent solar panel options, and the margin between them is narrow. The LONGi Hi-MO 7 620W wins 4 of 5 comparison dimensions by a slim margin. Your decision may come down to local pricing, installer availability, and which specific performance metrics matter most for your project. Either product is a solid investment.
Frequently Asked Questions
Which is better, LONGi Hi-MO 7 620W or LONGi Hi-MO X6 Max 470W?
The LONGi Hi-MO 7 620W wins this comparison by a narrow margin. It leads in efficiency (23% vs 22.3%). For most residential installations, the LONGi Hi-MO 7 620W is the stronger choice.
Which panel is more efficient, LONGi Hi-MO 7 620W or LONGi Hi-MO X6 Max 470W?
The LONGi Hi-MO 7 620W at 23% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 0.7 percentage points translates to approximately 150W per panel under standard test conditions.
Which has a better warranty, LONGi Hi-MO 7 620W or LONGi Hi-MO X6 Max 470W?
The LONGi Hi-MO 7 620W comes with a 12-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 3 additional years of product coverage.
Which panel performs better in hot weather?
The LONGi Hi-MO 7 620W has a temperature coefficient of -0.28%/°C and the LONGi Hi-MO X6 Max 470W is -0.29%/°C. LONGi Hi-MO 7 620W 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 7 620W vs LONGi Hi-MO X6 Max 470W panels do I need for an 8 kW system?
For an 8 kW system: you need 13 LONGi Hi-MO 7 620W panels (620W each) or 18 LONGi Hi-MO X6 Max 470W panels (470W each). The LONGi Hi-MO 7 620W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026