JA Solar JAM54S31 415W vs Hyundai HiE-S420VG
The Hyundai HiE-S420VG wins this comparison by a decisive margin. It delivers more power (420W vs 415W). For most residential installations, the Hyundai HiE-S420VG is the stronger choice.
Key Differences
- • JA Solar JAM54S31 415W is rated at 415W while Hyundai HiE-S420VG is rated at 420W, a 5W difference.
- • Both achieve identical 21.5% module efficiency.
- • Hyundai HiE-S420VG comes with a 25-year product warranty vs 12 years for the other.
- • Hyundai HiE-S420VG has a superior temperature coefficient of -0.3%/°C vs -0.34%/°C, retaining more power in hot climates.
- • JA Solar JAM54S31 415W uses PERC Mono cells while Hyundai HiE-S420VG uses TOPCon N-type cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
Both the JA Solar JAM54S31 415W and Hyundai HiE-S420VG share identical 21.5% module efficiency, producing comparable power per unit area. The JA Solar JAM54S31 415W generates 212.5 W/m² while the Hyundai HiE-S420VG generates 215.1 W/m² based on their respective panel dimensions. With matched efficiency, neither panel holds a density advantage for space-constrained rooftop installations, so other factors like warranty coverage and temperature performance become the deciding metrics.
Power Output
The Hyundai HiE-S420VG delivers 420W per panel versus 415W for the JA Solar JAM54S31 415W, a 5W difference per module. To build an 8 kW residential system, you would need 20 JA Solar JAM54S31 415W panels or 20 Hyundai HiE-S420VG 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 Hyundai HiE-S420VG has a temperature coefficient of -0.3%/°C versus -0.34%/°C for the JA Solar JAM54S31 415W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the Hyundai HiE-S420VG retains 94.0% of its rated power while the other retains 93.2%. 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 JA Solar JAM54S31 415W is backed by a 12-year product warranty and 25-year performance guarantee, while the Hyundai HiE-S420VG offers 25-year product and 25-year performance coverage. The Hyundai HiE-S420VG provides 13 additional years of defect protection, covering manufacturing issues, material failures, and premature performance loss. Based on their published degradation rates (1.5% first year then 0.5%/year for JA Solar JAM54S31 415W; 1% first year then 0.4%/year for Hyundai HiE-S420VG), after 25 years the JA Solar JAM54S31 415W should retain approximately 86.5% of original output versus 89.4% for the Hyundai HiE-S420VG. This 2.9 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.
Physical Dimensions & Weight
The JA Solar JAM54S31 415W measures 1722×1134×30mm and weighs 21.5 kg, while the Hyundai HiE-S420VG measures 1722×1134×30mm at 21 kg. 1.95 m² of panel area for the JA Solar JAM54S31 415W versus 1.95 m² for the Hyundai HiE-S420VG. 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 | JA Solar JAM54S31 415W | Hyundai HiE-S420VG |
|---|---|---|
| Power | 415W | 420W |
| Efficiency | 21.5% | 21.5% |
| Power Density | 19.7 W/sq ft | 20.0 W/sq ft |
| Cell Type | PERC Mono | TOPCon N-type |
| Bifacial | No | No |
| Weight | 21.5 kg | 21 kg |
| Temp Coefficient | -0.34%/°C | -0.3%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 2400 Pa | 2400 Pa |
| Product Warranty | 12 years | 25 years |
| Performance Warranty | 25 years | 25 years |
| Degradation (Year 1) | 1.5% | 1% |
| Annual Degradation | 0.5% | 0.4% |
| Country | China | South Korea |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: TieBoth panels achieve 21.5% module efficiency, producing identical power per square meter. Neither has an advantage in space-constrained installations.
2. Hot Climate Performance
Winner: Hyundai HiE-S420VGThe Hyundai HiE-S420VG has a better temperature coefficient of -0.3%/°C versus -0.34%/°C. On a 45°C summer day (20°C above STC), the winner retains 94.0% of rated power versus 93.2%. The difference is modest but accumulates over 25 years of summer production.
3. Durability & Warranty
Winner: Hyundai HiE-S420VGHyundai HiE-S420VG leads with a 25-year product warranty versus 12 years. Hyundai HiE-S420VG degrades more slowly at 0.4% per year versus 0.5%. After 25 years, expect 86.5% vs 89.4% of original output for JA Solar JAM54S31 415W and Hyundai HiE-S420VG respectively.
4. Power Output
Winner: Hyundai HiE-S420VGThe Hyundai HiE-S420VG delivers 420W versus 415W per panel — 5W more. For an 8 kW system, you need 20 panels with the higher-wattage option versus 20 panels, saving 0 panels and the associated racking and labor costs.
5. Cell Technology
Winner: Hyundai HiE-S420VGThe JA Solar JAM54S31 415W uses PERC Mono: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. The Hyundai HiE-S420VG 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. TOPCon N-type represents a newer generation technology with a longer performance runway as manufacturing matures.
JA Solar JAM54S31 415W
The JAM54S31 is a compact residential PERC panel delivering 415W with a solid balance of performance and affordability.
Pros
- + Compact residential form factor
- + Good price-performance ratio
- + Widely available
- + Proven reliability
Cons
- - Lower efficiency vs N-type
- - Higher degradation rate
- - Standard warranty
Hyundai HiE-S420VG
The Hyundai HiE-S420VG is a 420W residential-format TOPCon N-type panel in the popular 108-cell configuration (1722 x 1134mm), matching the most common residential panel size for easy racking and roof fit. Korean manufacturing provides supply chain diversification, and the TOPCon N-type cells deliver better temperature performance (-0.30%/°C) and lower degradation than PERC alternatives. The standard residential form factor ensures compatibility with all major racking systems.
Pros
- + Standard 108-cell residential size — fits any racking system
- + Korean-made TOPCon N-type with 21.5% efficiency
- + -0.30%/°C temperature coefficient for hot climate performance
- + 25+25 year warranty backed by Hyundai corporate
- + Non-Chinese manufacturing for tariff and UFLPA considerations
- + 420W competitive output in standard residential format
Cons
- - 420W is competitive but not class-leading for 108-cell panels
- - Slightly higher per-watt cost than Chinese equivalents
- - Smaller US installer network and distribution
- - Less brand recognition in solar market despite Hyundai name
Choose JA Solar JAM54S31 415W If...
- ✓ Budget residential installations seeking reliable PERC performance.
Choose Hyundai HiE-S420VG If...
- ✓ You want fewer panels to reach your target system size, reducing racking and labor costs
- ✓ Long-term warranty protection is a top priority and you plan to stay in your home for 25+ years
- ✓ 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
- ✓ You prefer newer cell technology with a longer performance improvement runway
Our Recommendation
The Hyundai HiE-S420VG is the decisive winner in this solar panel comparison, outperforming the JA Solar JAM54S31 415W in 4 of 5 dimensions. Unless you have a specific requirement that the JA Solar JAM54S31 415W uniquely addresses, the Hyundai HiE-S420VG is the stronger choice for virtually every installation scenario.
Frequently Asked Questions
Which is better, JA Solar JAM54S31 415W or Hyundai HiE-S420VG?
The Hyundai HiE-S420VG wins this comparison by a decisive margin. It delivers more power (420W vs 415W). For most residential installations, the Hyundai HiE-S420VG is the stronger choice.
Which panel is more efficient, JA Solar JAM54S31 415W or Hyundai HiE-S420VG?
The both panels share 21.5% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 0.0 percentage points translates to approximately 5W per panel under standard test conditions.
Which has a better warranty, JA Solar JAM54S31 415W or Hyundai HiE-S420VG?
The JA Solar JAM54S31 415W comes with a 12-year product warranty and 25-year performance guarantee. The Hyundai HiE-S420VG offers 25-year product and 25-year performance warranties. Hyundai HiE-S420VG provides 13 additional years of product coverage.
Which panel performs better in hot weather?
The JA Solar JAM54S31 415W has a temperature coefficient of -0.34%/°C and the Hyundai HiE-S420VG is -0.3%/°C. Hyundai HiE-S420VG retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.
How many JA Solar JAM54S31 415W vs Hyundai HiE-S420VG panels do I need for an 8 kW system?
For an 8 kW system: you need 20 JA Solar JAM54S31 415W panels (415W each) or 20 Hyundai HiE-S420VG panels (420W each). The Hyundai HiE-S420VG requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026