Hyundai HiE-S420VG vs Heliene 108M10 420W
The Hyundai HiE-S420VG wins this comparison by a clear margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Hyundai HiE-S420VG is the stronger choice.
Key Differences
- • Both panels are rated at 420W, so the comparison comes down to efficiency, warranty, and technology.
- • Both achieve identical 21.5% module efficiency.
- • Both carry matching 25-year product warranties.
- • Hyundai HiE-S420VG has a superior temperature coefficient of -0.3%/°C vs -0.34%/°C, retaining more power in hot climates.
- • Hyundai HiE-S420VG uses TOPCon N-type cells while Heliene 108M10 420W uses Mono PERC Half-cut cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
Both the Hyundai HiE-S420VG and Heliene 108M10 420W share identical 21.5% module efficiency, producing comparable power per unit area. The Hyundai HiE-S420VG generates 215.1 W/m² while the Heliene 108M10 420W 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
Both panels are rated at 420W under standard test conditions (STC), requiring 20 panels each to build an 8 kW system. With identical wattage ratings, the power output dimension is a draw and does not favor either panel. The real differentiators become efficiency density, temperature behavior, and long-term degradation rates which determine actual field performance beyond the nameplate rating.
Temperature Coefficient
The Hyundai HiE-S420VG has a temperature coefficient of -0.3%/°C versus -0.34%/°C for the Heliene 108M10 420W. 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 Hyundai HiE-S420VG is backed by a 25-year product warranty and 25-year performance guarantee, while the Heliene 108M10 420W offers 25-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 Hyundai HiE-S420VG; 1.5% first year then 0.5%/year for Heliene 108M10 420W), after 25 years the Hyundai HiE-S420VG should retain approximately 89.4% of original output versus 86.5% for the Heliene 108M10 420W. This 2.9 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.
Physical Dimensions & Weight
The Hyundai HiE-S420VG measures 1722×1134×30mm and weighs 21 kg, while the Heliene 108M10 420W measures 1722×1134×30mm at 21.5 kg. 1.95 m² of panel area for the Hyundai HiE-S420VG versus 1.95 m² for the Heliene 108M10 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 | Hyundai HiE-S420VG | Heliene 108M10 420W |
|---|---|---|
| Power | 420W | 420W |
| Efficiency | 21.5% | 21.5% |
| Power Density | 20.0 W/sq ft | 20.0 W/sq ft |
| Cell Type | TOPCon N-type | Mono PERC Half-cut |
| Bifacial | No | No |
| Weight | 21 kg | 21.5 kg |
| Temp Coefficient | -0.3%/°C | -0.34%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 2400 Pa | 2400 Pa |
| Product Warranty | 25 years | 25 years |
| Performance Warranty | 25 years | 25 years |
| Degradation (Year 1) | 1% | 1.5% |
| Annual Degradation | 0.4% | 0.5% |
| Country | South Korea | Canada |
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 degrades more slowly at 0.4% per year versus 0.5%. After 25 years, expect 89.4% vs 86.5% of original output for Hyundai HiE-S420VG and Heliene 108M10 420W respectively.
4. Power Output
Winner: TieBoth panels deliver 420W — identical power output per panel. System cost per watt will be the deciding factor.
5. Cell Technology
Winner: Hyundai HiE-S420VGThe 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. The Heliene 108M10 420W uses Mono PERC Half-cut: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. TOPCon N-type represents a newer generation technology with a longer performance runway as manufacturing matures.
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
Heliene 108M10 420W
The Heliene 108M10 420W is a standard residential-format mono PERC panel manufactured in Heliene's North American facilities (Ontario, Canada and Mountain Iron, Minnesota). The 108 half-cut cell design in the standard 1722 x 1134mm format ensures universal racking compatibility. As one of the few PERC panels made in North America, it offers domestic content ITC bonus eligibility at a more accessible price point than Heliene's HJT line. Backed by Heliene's 25-year product warranty and accessible Canadian/US-based support.
Pros
- + North American manufactured — domestic content ITC bonus eligible
- + Standard 108-cell residential format fits all racking systems
- + More affordable than HJT panels while qualifying for domestic content bonus
- + 25-year product and performance warranties
- + Canadian and US-based customer support
- + 420W competitive output for standard residential size
Cons
- - PERC technology — less efficient than TOPCon/HJT in hot climates
- - -0.34%/°C temp coefficient is standard, not exceptional
- - 420W is competitive but not class-leading
- - Higher cost than Chinese-made PERC panels of similar specs
Choose Hyundai HiE-S420VG If...
- ✓ 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
- ✓ Residential homeowners wanting a standard-size Korean-manufactured TOPCon panel that fits any roof and racking system with strong corporate warranty backing.
Choose Heliene 108M10 420W If...
- ✓ Budget-conscious homeowners who want North American-made panels for domestic content ITC bonus without paying the HJT premium.
Our Recommendation
We recommend the Hyundai HiE-S420VG for most buyers in this comparison. It wins 3 of 5 key dimensions and offers a clear advantage in the metrics that matter most for a solar panel purchase. The Heliene 108M10 420W remains a good product, but the Hyundai HiE-S420VG delivers better overall value for the majority of installations.
Frequently Asked Questions
Which is better, Hyundai HiE-S420VG or Heliene 108M10 420W?
The Hyundai HiE-S420VG wins this comparison by a clear margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Hyundai HiE-S420VG is the stronger choice.
Which panel is more efficient, Hyundai HiE-S420VG or Heliene 108M10 420W?
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 0W per panel under standard test conditions.
Which has a better warranty, Hyundai HiE-S420VG or Heliene 108M10 420W?
The Hyundai HiE-S420VG comes with a 25-year product warranty and 25-year performance guarantee. The Heliene 108M10 420W offers 25-year product and 25-year performance warranties. Both offer identical warranty terms.
Which panel performs better in hot weather?
The Hyundai HiE-S420VG has a temperature coefficient of -0.3%/°C and the Heliene 108M10 420W is -0.34%/°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 Hyundai HiE-S420VG vs Heliene 108M10 420W panels do I need for an 8 kW system?
For an 8 kW system: you need 20 Hyundai HiE-S420VG panels (420W each) or 20 Heliene 108M10 420W panels (420W each). Both require the same number of panels.
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Last updated: February 2026