LONGi Hi-MO 7 590W vs LONGi Hi-MO X6 445W
The LONGi Hi-MO 7 590W wins this comparison by a clear margin. It leads in efficiency (22.8% vs 22%) and matches or exceeds on warranty (12 vs 12 years). For most residential installations, the LONGi Hi-MO 7 590W is the stronger choice.
Key Differences
- • LONGi Hi-MO 7 590W is rated at 590W while LONGi Hi-MO X6 445W is rated at 445W, a 145W difference.
- • LONGi Hi-MO 7 590W achieves 22.8% efficiency vs 22% for the other, a 0.8 percentage point gap.
- • Both carry matching 12-year product warranties.
- • LONGi Hi-MO 7 590W has a superior temperature coefficient of -0.28%/°C vs -0.29%/°C, retaining more power in hot climates.
- • LONGi Hi-MO 7 590W uses HPBC (Back Contact N-type) cells while LONGi Hi-MO X6 445W uses TOPCon N-type cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
The LONGi Hi-MO 7 590W achieves 22.8% module efficiency compared to LONGi Hi-MO X6 445W's 22%, meaning LONGi Hi-MO 7 590W converts 0.8 percentage points more sunlight into electricity per square meter. In practical terms, the LONGi Hi-MO 7 590W produces 228.4 watts per square meter of panel area while the LONGi Hi-MO X6 445W produces 227.9 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 590W delivers 590W per panel versus 445W for the LONGi Hi-MO X6 445W, a 145W difference per module. To build an 8 kW residential system, you would need 14 LONGi Hi-MO 7 590W panels or 18 LONGi Hi-MO X6 445W panels. Choosing the higher-wattage option saves 4 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 590W has a temperature coefficient of -0.28%/°C versus -0.29%/°C for the LONGi Hi-MO X6 445W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the LONGi Hi-MO 7 590W 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 590W is backed by a 12-year product warranty and 30-year performance guarantee, while the LONGi Hi-MO X6 445W offers 12-year product and 25-year performance coverage. Both offer identical product warranty duration. Based on their published degradation rates (1% first year then 0.4%/year for LONGi Hi-MO 7 590W; 1% first year then 0.4%/year for LONGi Hi-MO X6 445W), after 25 years the LONGi Hi-MO 7 590W should retain approximately 89.4% of original output versus 89.4% for the LONGi Hi-MO X6 445W. The end-of-life output levels are closely matched.
Physical Dimensions & Weight
The LONGi Hi-MO 7 590W measures 2278×1134×35mm and weighs 28.8 kg, while the LONGi Hi-MO X6 445W measures 1722×1134×30mm at 21.5 kg. 2.58 m² of panel area for the LONGi Hi-MO 7 590W versus 1.95 m² for the LONGi Hi-MO X6 445W. The LONGi Hi-MO X6 445W is 7.3 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 146 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 7 590W | LONGi Hi-MO X6 445W |
|---|---|---|
| Power | 590W | 445W |
| Efficiency | 22.8% | 22% |
| Power Density | 21.2 W/sq ft | 21.2 W/sq ft |
| Cell Type | HPBC (Back Contact N-type) | TOPCon N-type |
| Bifacial | Yes | Yes |
| Weight | 28.8 kg | 21.5 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 | 12 years |
| Performance Warranty | 30 years | 25 years |
| Degradation (Year 1) | 1% | 1% |
| Annual Degradation | 0.4% | 0.4% |
| Country | China | China |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: LONGi Hi-MO 7 590WThe LONGi Hi-MO 7 590W achieves 22.8% efficiency versus 22% — a 0.8 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 4.3 kW more total system capacity, or 20 kWh more annual production in an average US location.
2. Hot Climate Performance
Winner: LONGi Hi-MO 7 590WThe LONGi Hi-MO 7 590W 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: TieBoth panels offer identical 12-year product warranties and 0.4% annual degradation. Neither has a durability advantage.
4. Power Output
Winner: LONGi Hi-MO 7 590WThe LONGi Hi-MO 7 590W delivers 590W versus 445W per panel — 145W more. For an 8 kW system, you need 14 panels with the higher-wattage option versus 18 panels, saving 4 panels and the associated racking and labor costs.
5. Cell Technology
Winner: LONGi Hi-MO 7 590WThe LONGi Hi-MO 7 590W 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 445W 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 590W
The Hi-MO 7 is LONGi's flagship residential panel using proprietary HPBC (Hybrid Passivated Back Contact) cell technology for exceptional 22.8% efficiency and 590W output.
Pros
- + Industry-leading HPBC back-contact technology
- + 22.8% efficiency
- + Excellent temperature coefficient
- + Lower degradation rate
Cons
- - Premium pricing
- - Heavy at 28.8 kg
- - New technology with limited track record
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
Choose LONGi Hi-MO 7 590W 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
- ✓ Premium residential installations seeking maximum efficiency.
Choose LONGi Hi-MO X6 445W If...
- ✓ You prefer newer cell technology with a longer performance improvement runway
- ✓ Homeowners wanting N-type TOPCon technology in a compact residential format.
Our Recommendation
We recommend the LONGi Hi-MO 7 590W for most buyers in this comparison. It wins 4 of 5 key dimensions and offers a clear advantage in the metrics that matter most for a solar panel purchase. The LONGi Hi-MO X6 445W remains a good product, but the LONGi Hi-MO 7 590W delivers better overall value for the majority of installations.
Frequently Asked Questions
Which is better, LONGi Hi-MO 7 590W or LONGi Hi-MO X6 445W?
The LONGi Hi-MO 7 590W wins this comparison by a clear margin. It leads in efficiency (22.8% vs 22%) and matches or exceeds on warranty (12 vs 12 years). For most residential installations, the LONGi Hi-MO 7 590W is the stronger choice.
Which panel is more efficient, LONGi Hi-MO 7 590W or LONGi Hi-MO X6 445W?
The LONGi Hi-MO 7 590W 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 0.8 percentage points translates to approximately 145W per panel under standard test conditions.
Which has a better warranty, LONGi Hi-MO 7 590W or LONGi Hi-MO X6 445W?
The LONGi Hi-MO 7 590W comes with a 12-year product warranty and 30-year performance guarantee. The LONGi Hi-MO X6 445W 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 7 590W has a temperature coefficient of -0.28%/°C and the LONGi Hi-MO X6 445W is -0.29%/°C. LONGi Hi-MO 7 590W 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 590W vs LONGi Hi-MO X6 445W panels do I need for an 8 kW system?
For an 8 kW system: you need 14 LONGi Hi-MO 7 590W panels (590W each) or 18 LONGi Hi-MO X6 445W panels (445W each). The LONGi Hi-MO 7 590W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026