Silfab SIL-370-BK 370W vs ZNShine Solar ZXM6-SHLD108 420W

Our Verdict Winner: Silfab SIL-370-BK 370W

The Silfab SIL-370-BK 370W wins this comparison by a decisive margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Silfab SIL-370-BK 370W is the stronger choice.

Power / Capacity
370W
vs
420W
Efficiency
20.4%
vs
21%
Warranty
25 yrs
vs
12 yrs

Key Differences

  • Silfab SIL-370-BK 370W is rated at 370W while ZNShine Solar ZXM6-SHLD108 420W is rated at 420W, a 50W difference.
  • ZNShine Solar ZXM6-SHLD108 420W achieves 21% efficiency vs 20.4% for the other, a 0.6 percentage point gap.
  • Silfab SIL-370-BK 370W comes with a 25-year product warranty vs 12 years for the other.
  • ZNShine Solar ZXM6-SHLD108 420W has a superior temperature coefficient of -0.34%/°C vs -0.35%/°C, retaining more power in hot climates.

Specifications Breakdown

Module Efficiency

The ZNShine Solar ZXM6-SHLD108 420W achieves 21% module efficiency compared to Silfab SIL-370-BK 370W's 20.4%, meaning ZNShine Solar ZXM6-SHLD108 420W converts 0.6 percentage points more sunlight into electricity per square meter. In practical terms, the Silfab SIL-370-BK 370W produces 189.5 watts per square meter of panel area while the ZNShine Solar ZXM6-SHLD108 420W produces 215.1 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 ZNShine Solar ZXM6-SHLD108 420W delivers 420W per panel versus 370W for the Silfab SIL-370-BK 370W, a 50W difference per module. To build an 8 kW residential system, you would need 22 Silfab SIL-370-BK 370W panels or 20 ZNShine Solar ZXM6-SHLD108 420W 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

The ZNShine Solar ZXM6-SHLD108 420W has a temperature coefficient of -0.34%/°C versus -0.35%/°C for the Silfab SIL-370-BK 370W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the ZNShine Solar ZXM6-SHLD108 420W 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 Silfab SIL-370-BK 370W is backed by a 25-year product warranty and 25-year performance guarantee, while the ZNShine Solar ZXM6-SHLD108 420W offers 12-year product and 25-year performance coverage. The Silfab SIL-370-BK 370W 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 Silfab SIL-370-BK 370W; 1.5% first year then 0.5%/year for ZNShine Solar ZXM6-SHLD108 420W), after 25 years the Silfab SIL-370-BK 370W should retain approximately 89.4% of original output versus 86.5% for the ZNShine Solar ZXM6-SHLD108 420W. This 2.9 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.

Physical Dimensions & Weight

The Silfab SIL-370-BK 370W measures 1722×1134×30mm and weighs 19.5 kg, while the ZNShine Solar ZXM6-SHLD108 420W measures 1722×1134×30mm at 21 kg. 1.95 m² of panel area for the Silfab SIL-370-BK 370W versus 1.95 m² for the ZNShine Solar ZXM6-SHLD108 420W. 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 Silfab SIL-370-BK 370W ZNShine Solar ZXM6-SHLD108 420W
Power 370W 420W
Efficiency 20.4% 21%
Power Density 17.6 W/sq ft 20.0 W/sq ft
Cell Type PERC Mono PERC Mono
Bifacial No No
Weight 19.5 kg 21 kg
Temp Coefficient -0.35%/°C -0.34%/°C
Snow Load 2400 Pa 5400 Pa
Wind Load 2400 Pa 2400 Pa
Product Warranty 25 years 12 years
Performance Warranty 25 years 25 years
Degradation (Year 1) 1% 1.5%
Annual Degradation 0.4% 0.5%
Country United States China

5-Dimension Head-to-Head Analysis

1. Efficiency & Power Density

Winner: ZNShine Solar ZXM6-SHLD108 420W

The ZNShine Solar ZXM6-SHLD108 420W achieves 21% efficiency versus 20.4% — a 0.6 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 1.5 kW more total system capacity, or 7 kWh more annual production in an average US location.

2. Hot Climate Performance

Winner: ZNShine Solar ZXM6-SHLD108 420W

The ZNShine Solar ZXM6-SHLD108 420W 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: Silfab SIL-370-BK 370W

Silfab SIL-370-BK 370W leads with a 25-year product warranty versus 12 years. Silfab SIL-370-BK 370W degrades more slowly at 0.4% per year versus 0.5%. After 25 years, expect 89.4% vs 86.5% of original output for Silfab SIL-370-BK 370W and ZNShine Solar ZXM6-SHLD108 420W respectively.

4. Power Output

Winner: ZNShine Solar ZXM6-SHLD108 420W

The ZNShine Solar ZXM6-SHLD108 420W delivers 420W versus 370W per panel — 50W more. For an 8 kW system, you need 20 panels with the higher-wattage option versus 22 panels, saving 2 panels and the associated racking and labor costs.

5. Cell Technology

Winner: Tie

Both panels use PERC Mono cell technology. No technology advantage for either product.

Silfab SIL-370-BK 370W

The SIL-370-BK is Silfab's entry-level US-made all-black panel delivering 370W for budget-conscious domestic installations.

Pros

  • + Made in USA
  • + All-black design
  • + 25-year warranty
  • + ARRA compliant

Cons

  • - Lower wattage
  • - Basic PERC technology
  • - Less competitive efficiency
View full Silfab SIL-370-BK 370W specs →

ZNShine Solar ZXM6-SHLD108 420W

ZNShine Solar ZXM6 delivers 420W with PERC technology and optional graphene coating for enhanced durability and performance.

Pros

  • + Graphene glass option
  • + Compact residential size
  • + Good PERC performance
  • + Unique coating technology

Cons

  • - Niche brand
  • - Limited availability
  • - Standard PERC efficiency
View full ZNShine Solar ZXM6-SHLD108 420W specs →

Choose Silfab SIL-370-BK 370W If...

  • Long-term warranty protection is a top priority and you plan to stay in your home for 25+ years
  • You want maximum output retention over the system's 25-30 year lifespan
  • Government or institutional projects requiring ARRA/Buy America compliance.

Choose ZNShine Solar ZXM6-SHLD108 420W 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
  • Residential installations wanting graphene-enhanced glass for improved soiling resistance.

Our Recommendation

Recommended Silfab SIL-370-BK 370W

The Silfab SIL-370-BK 370W is the decisive winner in this solar panel comparison, outperforming the ZNShine Solar ZXM6-SHLD108 420W in 1 of 5 dimensions. Unless you have a specific requirement that the ZNShine Solar ZXM6-SHLD108 420W uniquely addresses, the Silfab SIL-370-BK 370W is the stronger choice for virtually every installation scenario.

Frequently Asked Questions

Which is better, Silfab SIL-370-BK 370W or ZNShine Solar ZXM6-SHLD108 420W?

The Silfab SIL-370-BK 370W wins this comparison by a decisive margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Silfab SIL-370-BK 370W is the stronger choice.

Which panel is more efficient, Silfab SIL-370-BK 370W or ZNShine Solar ZXM6-SHLD108 420W?

The ZNShine Solar ZXM6-SHLD108 420W at 21% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 0.6 percentage points translates to approximately 50W per panel under standard test conditions.

Which has a better warranty, Silfab SIL-370-BK 370W or ZNShine Solar ZXM6-SHLD108 420W?

The Silfab SIL-370-BK 370W comes with a 25-year product warranty and 25-year performance guarantee. The ZNShine Solar ZXM6-SHLD108 420W offers 12-year product and 25-year performance warranties. Silfab SIL-370-BK 370W provides 13 additional years of product coverage.

Which panel performs better in hot weather?

The Silfab SIL-370-BK 370W has a temperature coefficient of -0.35%/°C and the ZNShine Solar ZXM6-SHLD108 420W is -0.34%/°C. ZNShine Solar ZXM6-SHLD108 420W retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.

How many Silfab SIL-370-BK 370W vs ZNShine Solar ZXM6-SHLD108 420W panels do I need for an 8 kW system?

For an 8 kW system: you need 22 Silfab SIL-370-BK 370W panels (370W each) or 20 ZNShine Solar ZXM6-SHLD108 420W panels (420W each). The ZNShine Solar ZXM6-SHLD108 420W requires fewer panels, saving on racking hardware and installation labor.

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Last updated: February 2026