Panasonic EVPV400H vs Seraphim S4 Series 430W
The Panasonic EVPV400H wins this comparison by a decisive margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Panasonic EVPV400H is the stronger choice.
Key Differences
- • Panasonic EVPV400H is rated at 400W while Seraphim S4 Series 430W is rated at 430W, a 30W difference.
- • Both achieve identical 21.2% module efficiency.
- • Panasonic EVPV400H comes with a 25-year product warranty vs 12 years for the other.
- • Panasonic EVPV400H has a superior temperature coefficient of -0.26%/°C vs -0.34%/°C, retaining more power in hot climates.
- • Panasonic EVPV400H uses HJT (Heterojunction) cells while Seraphim S4 Series 430W uses PERC Mono cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
Both the Panasonic EVPV400H and Seraphim S4 Series 430W share identical 21.2% module efficiency, producing comparable power per unit area. The Panasonic EVPV400H generates 204.8 W/m² while the Seraphim S4 Series 430W generates 220.2 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 Seraphim S4 Series 430W delivers 430W per panel versus 400W for the Panasonic EVPV400H, a 30W difference per module. To build an 8 kW residential system, you would need 20 Panasonic EVPV400H panels or 19 Seraphim S4 Series 430W panels. Choosing the higher-wattage option saves 1 panel, 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 Panasonic EVPV400H has a temperature coefficient of -0.26%/°C versus -0.34%/°C for the Seraphim S4 Series 430W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the Panasonic EVPV400H retains 94.8% of its rated power while the other retains 93.2%. This difference is particularly significant in hot climates such as the American Southwest, the Middle East, and Southeast Asia, where panels routinely operate 30-40°C above STC for several hours each day. Over the system lifetime, the cumulative energy advantage from a better temperature coefficient can amount to 2-4% of total production.
Warranty Coverage
The Panasonic EVPV400H is backed by a 25-year product warranty and 25-year performance guarantee, while the Seraphim S4 Series 430W offers 12-year product and 25-year performance coverage. The Panasonic EVPV400H provides 13 additional years of defect protection, covering manufacturing issues, material failures, and premature performance loss. Based on their published degradation rates (0.5% first year then 0.35%/year for Panasonic EVPV400H; 1.5% first year then 0.5%/year for Seraphim S4 Series 430W), after 25 years the Panasonic EVPV400H should retain approximately 91.1% of original output versus 86.5% for the Seraphim S4 Series 430W. This 4.6 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.
Physical Dimensions & Weight
The Panasonic EVPV400H measures 1722×1134×30mm and weighs 21 kg, while the Seraphim S4 Series 430W measures 1722×1134×30mm at 21 kg. 1.95 m² of panel area for the Panasonic EVPV400H versus 1.95 m² for the Seraphim S4 Series 430W. 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 | Panasonic EVPV400H | Seraphim S4 Series 430W |
|---|---|---|
| Power | 400W | 430W |
| Efficiency | 21.2% | 21.2% |
| Power Density | 19.0 W/sq ft | 20.5 W/sq ft |
| Cell Type | HJT (Heterojunction) | PERC Mono |
| Bifacial | Yes | No |
| Weight | 21 kg | 21 kg |
| Temp Coefficient | -0.26%/°C | -0.34%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 2400 Pa | 2400 Pa |
| Product Warranty | 25 years | 12 years |
| Performance Warranty | 25 years | 25 years |
| Degradation (Year 1) | 0.5% | 1.5% |
| Annual Degradation | 0.35% | 0.5% |
| Country | Japan | China |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: TieBoth panels achieve 21.2% module efficiency, producing identical power per square meter. Neither has an advantage in space-constrained installations.
2. Hot Climate Performance
Winner: Panasonic EVPV400HThe Panasonic EVPV400H has a better temperature coefficient of -0.26%/°C versus -0.34%/°C. On a 45°C summer day (20°C above STC), the winner retains 94.8% of rated power versus 93.2%. This is a meaningful difference in hot states like Arizona, Texas, and Florida.
3. Durability & Warranty
Winner: Panasonic EVPV400HPanasonic EVPV400H leads with a 25-year product warranty versus 12 years. Panasonic EVPV400H degrades more slowly at 0.35% per year versus 0.5%. After 25 years, expect 91.1% vs 86.5% of original output for Panasonic EVPV400H and Seraphim S4 Series 430W respectively.
4. Power Output
Winner: Seraphim S4 Series 430WThe Seraphim S4 Series 430W delivers 430W versus 400W per panel — 30W more. For an 8 kW system, you need 19 panels with the higher-wattage option versus 20 panels, saving 1 panels and the associated racking and labor costs.
5. Cell Technology
Winner: Panasonic EVPV400HThe Panasonic EVPV400H uses HJT (Heterojunction): HJT (Heterojunction) combines crystalline silicon with amorphous silicon layers, delivering the best temperature coefficient and bifacial gains, but at higher manufacturing cost. The Seraphim S4 Series 430W uses PERC Mono: PERC (Passivated Emitter Rear Cell) is the current mainstream technology, offering good efficiency at the lowest manufacturing cost. HJT (Heterojunction) represents a newer generation technology with a longer performance runway as manufacturing matures.
Panasonic EVPV400H
DISCONTINUED: Panasonic exited solar manufacturing in 2023. The EVPV400H was Panasonic's standard HJT residential panel, delivering 400W with the brand's signature quality and longevity.
Pros
- + Panasonic reliability
- + HJT advantages
- + Solid 25-year warranty
- + Good all-round performer
Cons
- - DISCONTINUED - no longer manufactured
- - No new units available
- - No ongoing product support
Seraphim S4 Series 430W
The Seraphim S4 Series delivers 430W using proven PERC technology at a competitive price point for residential installations.
Pros
- + Competitive pricing
- + Proven PERC technology
- + Compact design
- + Good value
Cons
- - Standard PERC efficiency
- - Shorter warranty period
- - Limited US presence
Choose Panasonic EVPV400H If...
- ✓ 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
- ✓ No longer available for new installations.
Choose Seraphim S4 Series 430W If...
- ✓ You want fewer panels to reach your target system size, reducing racking and labor costs
- ✓ Budget residential installations seeking competitive PERC pricing.
Our Recommendation
The Panasonic EVPV400H is the decisive winner in this solar panel comparison, outperforming the Seraphim S4 Series 430W in 3 of 5 dimensions. Unless you have a specific requirement that the Seraphim S4 Series 430W uniquely addresses, the Panasonic EVPV400H is the stronger choice for virtually every installation scenario.
Frequently Asked Questions
Which is better, Panasonic EVPV400H or Seraphim S4 Series 430W?
The Panasonic EVPV400H wins this comparison by a decisive margin. It offers better long-term durability with 25-year warranty. For most residential installations, the Panasonic EVPV400H is the stronger choice.
Which panel is more efficient, Panasonic EVPV400H or Seraphim S4 Series 430W?
The both panels share 21.2% 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 30W per panel under standard test conditions.
Which has a better warranty, Panasonic EVPV400H or Seraphim S4 Series 430W?
The Panasonic EVPV400H comes with a 25-year product warranty and 25-year performance guarantee. The Seraphim S4 Series 430W offers 12-year product and 25-year performance warranties. Panasonic EVPV400H provides 13 additional years of product coverage.
Which panel performs better in hot weather?
The Panasonic EVPV400H has a temperature coefficient of -0.26%/°C and the Seraphim S4 Series 430W is -0.34%/°C. Panasonic EVPV400H retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.
How many Panasonic EVPV400H vs Seraphim S4 Series 430W panels do I need for an 8 kW system?
For an 8 kW system: you need 20 Panasonic EVPV400H panels (400W each) or 19 Seraphim S4 Series 430W panels (430W each). The Seraphim S4 Series 430W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026