LONGi Hi-MO 7 590W vs Tongwei THN-EP08M10 580W

Our Verdict Winner: LONGi Hi-MO 7 590W

The LONGi Hi-MO 7 590W wins this comparison by a narrow margin. It leads in efficiency (22.8% vs 22.5%) and matches or exceeds on warranty (12 vs 12 years). For most residential installations, the LONGi Hi-MO 7 590W is the stronger choice.

Power / Capacity
590W
vs
580W
Efficiency
22.8%
vs
22.5%
Warranty
12 yrs
vs
12 yrs

Key Differences

  • LONGi Hi-MO 7 590W is rated at 590W while Tongwei THN-EP08M10 580W is rated at 580W, a 10W difference.
  • LONGi Hi-MO 7 590W achieves 22.8% efficiency vs 22.5% for the other, a 0.3 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 Tongwei THN-EP08M10 580W 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 Tongwei THN-EP08M10 580W's 22.5%, meaning LONGi Hi-MO 7 590W converts 0.3 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 Tongwei THN-EP08M10 580W produces 224.5 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 7 590W delivers 590W per panel versus 580W for the Tongwei THN-EP08M10 580W, a 10W difference per module. To build an 8 kW residential system, you would need 14 LONGi Hi-MO 7 590W panels or 14 Tongwei THN-EP08M10 580W 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 LONGi Hi-MO 7 590W has a temperature coefficient of -0.28%/°C versus -0.29%/°C for the Tongwei THN-EP08M10 580W. 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 Tongwei THN-EP08M10 580W 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 Tongwei THN-EP08M10 580W), after 25 years the LONGi Hi-MO 7 590W should retain approximately 89.4% of original output versus 89.4% for the Tongwei THN-EP08M10 580W. 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 Tongwei THN-EP08M10 580W measures 2278×1134×35mm at 28.5 kg. 2.58 m² of panel area for the LONGi Hi-MO 7 590W versus 2.58 m² for the Tongwei THN-EP08M10 580W. Their weights are closely matched, so neither panel imposes a significantly different structural load on the mounting system. Similar footprints mean both panels fit comparably on standard residential rooftop configurations.

Specification Comparison

Specification LONGi Hi-MO 7 590W Tongwei THN-EP08M10 580W
Power 590W 580W
Efficiency 22.8% 22.5%
Power Density 21.2 W/sq ft 20.9 W/sq ft
Cell Type HPBC (Back Contact N-type) TOPCon N-type
Bifacial Yes No
Weight 28.8 kg 28.5 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 590W

The LONGi Hi-MO 7 590W achieves 22.8% efficiency versus 22.5% — a 0.3 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 0.3 kW more total system capacity, or 2 kWh more annual production in an average US location.

2. Hot Climate Performance

Winner: LONGi Hi-MO 7 590W

The 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: Tie

Both 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 590W

The LONGi Hi-MO 7 590W delivers 590W versus 580W per panel — 10W more. For an 8 kW system, you need 14 panels with the higher-wattage option versus 14 panels, saving 0 panels and the associated racking and labor costs.

5. Cell Technology

Winner: LONGi Hi-MO 7 590W

The 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 Tongwei THN-EP08M10 580W 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
View full LONGi Hi-MO 7 590W specs →

Tongwei THN-EP08M10 580W

Tongwei THN-EP08M10 is a high-output N-type TOPCon panel from one of the world's largest solar cell manufacturers.

Pros

  • + Top cell manufacturer
  • + High 580W output
  • + Competitive pricing
  • + Strong R&D backing

Cons

  • - Limited brand recognition outside China
  • - Standard warranty
  • - Newer to module market
View full Tongwei THN-EP08M10 580W specs →

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 Tongwei THN-EP08M10 580W If...

  • You prefer newer cell technology with a longer performance improvement runway
  • Large installations seeking competitive N-type pricing from a cell technology leader.

Our Recommendation

Recommended LONGi Hi-MO 7 590W

Both the LONGi Hi-MO 7 590W and Tongwei THN-EP08M10 580W are excellent solar panel options, and the margin between them is narrow. The LONGi Hi-MO 7 590W 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 590W or Tongwei THN-EP08M10 580W?

The LONGi Hi-MO 7 590W wins this comparison by a narrow margin. It leads in efficiency (22.8% vs 22.5%) 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 Tongwei THN-EP08M10 580W?

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 0.3 percentage points translates to approximately 10W per panel under standard test conditions.

Which has a better warranty, LONGi Hi-MO 7 590W or Tongwei THN-EP08M10 580W?

The LONGi Hi-MO 7 590W comes with a 12-year product warranty and 30-year performance guarantee. The Tongwei THN-EP08M10 580W 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 Tongwei THN-EP08M10 580W 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 Tongwei THN-EP08M10 580W 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 14 Tongwei THN-EP08M10 580W panels (580W 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