First Solar Series 7 545W vs Astronergy ASTRO N7 580W
The Astronergy ASTRO N7 580W wins this comparison by a decisive margin. It leads in efficiency (22.4% vs 19.8%) and matches or exceeds on warranty (15 vs 10 years). For most residential installations, the Astronergy ASTRO N7 580W is the stronger choice.
Key Differences
- • First Solar Series 7 545W is rated at 545W while Astronergy ASTRO N7 580W is rated at 580W, a 35W difference.
- • Astronergy ASTRO N7 580W achieves 22.4% efficiency vs 19.8% for the other, a 2.6 percentage point gap.
- • Astronergy ASTRO N7 580W comes with a 15-year product warranty vs 10 years for the other.
- • First Solar Series 7 545W has a superior temperature coefficient of -0.28%/°C vs -0.29%/°C, retaining more power in hot climates.
- • First Solar Series 7 545W uses CdTe (Cadmium Telluride) cells while Astronergy ASTRO N7 580W uses TOPCon N-type cells, representing different technology generations.
Specifications Breakdown
Module Efficiency
The Astronergy ASTRO N7 580W achieves 22.4% module efficiency compared to First Solar Series 7 545W's 19.8%, meaning Astronergy ASTRO N7 580W converts 2.6 percentage points more sunlight into electricity per square meter. In practical terms, the First Solar Series 7 545W produces 173.9 watts per square meter of panel area while the Astronergy ASTRO N7 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 Astronergy ASTRO N7 580W delivers 580W per panel versus 545W for the First Solar Series 7 545W, a 35W difference per module. To build an 8 kW residential system, you would need 15 First Solar Series 7 545W panels or 14 Astronergy ASTRO N7 580W 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 First Solar Series 7 545W has a temperature coefficient of -0.28%/°C versus -0.29%/°C for the Astronergy ASTRO N7 580W. On a hot summer day when cell temperature reaches 65°C (40°C above the 25°C STC baseline), the First Solar Series 7 545W 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 First Solar Series 7 545W is backed by a 10-year product warranty and 30-year performance guarantee, while the Astronergy ASTRO N7 580W offers 15-year product and 30-year performance coverage. The Astronergy ASTRO N7 580W provides 5 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 First Solar Series 7 545W; 1% first year then 0.4%/year for Astronergy ASTRO N7 580W), after 25 years the First Solar Series 7 545W should retain approximately 86.5% of original output versus 89.4% for the Astronergy ASTRO N7 580W. This 2.9 percentage point gap in end-of-life output meaningfully impacts lifetime energy economics.
Physical Dimensions & Weight
The First Solar Series 7 545W measures 2520×1244×49mm and weighs 38 kg, while the Astronergy ASTRO N7 580W measures 2278×1134×35mm at 28.5 kg. 3.13 m² of panel area for the First Solar Series 7 545W versus 2.58 m² for the Astronergy ASTRO N7 580W. The Astronergy ASTRO N7 580W is 9.5 kg lighter per panel, which reduces structural load requirements on the roof and makes handling easier during installation. For a 20-panel system, that is a total weight difference of 190 kg. The more compact Astronergy ASTRO N7 580W may be easier to fit on irregularly shaped or space-limited rooftops.
Specification Comparison
| Specification | First Solar Series 7 545W | Astronergy ASTRO N7 580W |
|---|---|---|
| Power | 545W | 580W |
| Efficiency | 19.8% | 22.4% |
| Power Density | 16.2 W/sq ft | 20.9 W/sq ft |
| Cell Type | CdTe (Cadmium Telluride) | TOPCon N-type |
| Bifacial | No | Yes |
| Weight | 38 kg | 28.5 kg |
| Temp Coefficient | -0.28%/°C | -0.29%/°C |
| Snow Load | 5400 Pa | 5400 Pa |
| Wind Load | 4000 Pa | 2400 Pa |
| Product Warranty | 10 years | 15 years |
| Performance Warranty | 30 years | 30 years |
| Degradation (Year 1) | 1.5% | 1% |
| Annual Degradation | 0.5% | 0.4% |
| Country | United States | China |
5-Dimension Head-to-Head Analysis
1. Efficiency & Power Density
Winner: Astronergy ASTRO N7 580WThe Astronergy ASTRO N7 580W achieves 22.4% efficiency versus 19.8% — a 2.6 percentage point advantage. On a typical 30-panel residential roof, this translates to approximately 1.1 kW more total system capacity, or 5 kWh more annual production in an average US location.
2. Hot Climate Performance
Winner: First Solar Series 7 545WThe First Solar Series 7 545W 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: Astronergy ASTRO N7 580WAstronergy ASTRO N7 580W leads with a 15-year product warranty versus 10 years. Astronergy ASTRO N7 580W degrades more slowly at 0.4% per year versus 0.5%. After 25 years, expect 86.5% vs 89.4% of original output for First Solar Series 7 545W and Astronergy ASTRO N7 580W respectively.
4. Power Output
Winner: Astronergy ASTRO N7 580WThe Astronergy ASTRO N7 580W delivers 580W versus 545W per panel — 35W more. For an 8 kW system, you need 14 panels with the higher-wattage option versus 15 panels, saving 1 panels and the associated racking and labor costs.
5. Cell Technology
Winner: Astronergy ASTRO N7 580WThe First Solar Series 7 545W uses CdTe (Cadmium Telluride): CdTe (Cadmium Telluride). The Astronergy ASTRO N7 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. TOPCon N-type represents a newer generation technology with a longer performance runway as manufacturing matures.
First Solar Series 7 545W
First Solar Series 7 is a US-made thin-film CdTe module delivering 545W with superior temperature performance and sustainable manufacturing.
Pros
- + US manufactured thin-film
- + Excellent hot weather performance
- + Lower carbon footprint
- + No supply chain issues
Cons
- - Lower efficiency than crystalline silicon
- - Very large and heavy
- - Not for residential roofs
Astronergy ASTRO N7 580W
Astronergy ASTRO N7 delivers 580W with TOPCon N-type technology, backed by CHINT Group's manufacturing scale and reliability.
Pros
- + High 580W output
- + N-type TOPCon efficiency
- + Strong manufacturing backing
- + Competitive pricing
Cons
- - Less known brand in US
- - Limited installer network
- - Large form factor
Choose First Solar Series 7 545W If...
- ✓ You live in a hot climate (Arizona, Texas, Florida) where heat performance matters
- ✓ Utility-scale projects valuing US manufacturing and hot-climate performance.
Choose Astronergy ASTRO N7 580W 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
- ✓ Long-term warranty protection is a top priority and you plan to stay in your home for 15+ years
- ✓ 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 Astronergy ASTRO N7 580W is the decisive winner in this solar panel comparison, outperforming the First Solar Series 7 545W in 4 of 5 dimensions. Unless you have a specific requirement that the First Solar Series 7 545W uniquely addresses, the Astronergy ASTRO N7 580W is the stronger choice for virtually every installation scenario.
Frequently Asked Questions
Which is better, First Solar Series 7 545W or Astronergy ASTRO N7 580W?
The Astronergy ASTRO N7 580W wins this comparison by a decisive margin. It leads in efficiency (22.4% vs 19.8%) and matches or exceeds on warranty (15 vs 10 years). For most residential installations, the Astronergy ASTRO N7 580W is the stronger choice.
Which panel is more efficient, First Solar Series 7 545W or Astronergy ASTRO N7 580W?
The Astronergy ASTRO N7 580W at 22.4% module efficiency. Higher efficiency means more watts per square foot of roof space, which is critical for space-constrained installations. The difference of 2.6 percentage points translates to approximately 35W per panel under standard test conditions.
Which has a better warranty, First Solar Series 7 545W or Astronergy ASTRO N7 580W?
The First Solar Series 7 545W comes with a 10-year product warranty and 30-year performance guarantee. The Astronergy ASTRO N7 580W offers 15-year product and 30-year performance warranties. Astronergy ASTRO N7 580W provides 5 additional years of product coverage.
Which panel performs better in hot weather?
The First Solar Series 7 545W has a temperature coefficient of -0.28%/°C and the Astronergy ASTRO N7 580W is -0.29%/°C. First Solar Series 7 545W retains more power in heat — important in states like Arizona, Texas, and Florida. A lower (less negative) temperature coefficient is better.
How many First Solar Series 7 545W vs Astronergy ASTRO N7 580W panels do I need for an 8 kW system?
For an 8 kW system: you need 15 First Solar Series 7 545W panels (545W each) or 14 Astronergy ASTRO N7 580W panels (580W each). The Astronergy ASTRO N7 580W requires fewer panels, saving on racking hardware and installation labor.
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Last updated: February 2026