First Solar Series 7 545W Specifications & Review
First Solar Series 7 is a US-made thin-film CdTe module delivering 545W with superior temperature performance and sustainable manufacturing.
What Makes the First Solar Series 7 545W Different
The First Solar Series 7 545W uses an entirely different technology from every other panel in our database — Cadmium Telluride (CdTe) thin-film instead of crystalline silicon. First Solar is the only major US-headquartered panel manufacturer and the world's largest thin-film producer, with manufacturing facilities in Ohio, Alabama, Louisiana, and India. CdTe thin-film panels have several unique advantages: a lower temperature coefficient than silicon, better performance in hot and humid conditions, and no reliance on polysilicon supply chains. At 545W and 19.8% efficiency, the Series 7 is designed for utility-scale projects. First Solar panels are manufactured entirely in the USA, qualifying for maximum IRA domestic content bonuses. The 2520×1244mm commercial format at 38 kg is optimized for utility-scale racking and tracker systems.
Key Specifications
| Brand | First Solar |
| Model | First Solar Series 7 545W |
| Power Output | 545W |
| Efficiency | 19.8% |
| Power Density | 16.2 W/sq ft |
| Cell Type | CdTe (Cadmium Telluride) |
| Cell Count | 144 cells |
| Dimensions | 2520 x 1244 x 49 mm |
| Weight | 38 kg |
| Open Circuit Voltage (Voc) | 230.5V |
| Max Power Voltage (Vmp) | 190V |
| Short Circuit Current (Isc) | 3.05A |
| Max Power Current (Imp) | 2.87A |
| Temp Coefficient (Pmax) | -0.28%/°C |
| Product Warranty | 10 years |
| Performance Warranty | 30 years |
| First Year Degradation | 1.5% |
| Annual Degradation | 0.5% |
| Country of Manufacture | United States |
| Certifications | IEC 61215, IEC 61730, UL 1703 |
| Snow Load | 5400 Pa (112.8 psf) — Heavy Snow Rated |
| Wind Load | 4000 Pa (83.5 psf) |
Pros & Cons
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
Best For
Utility-scale projects valuing US manufacturing and hot-climate performance.
Is the First Solar Series 7 545W Worth It?
The First Solar Series 7 545W delivers 545W of power at 19.8% module efficiency, which is below the current industry average of approximately 21%. While not the highest-efficiency option on the market, it may offer compelling value depending on price and your available roof space.
From a warranty perspective, the Series 7 545W comes with a standard 10-year product warranty and a 30-year performance guarantee. The industry standard for product warranties ranges from 12 to 25 years, so you may want to weigh this shorter warranty against the overall system cost. At the end of 30 years, the panel is guaranteed to still produce approximately 84.0% of its rated output, with first-year degradation of 1.5% and just 0.5% per year after that.
Pricing varies by region and installer, but the Series 7 545W's combination of 19.8% efficiency and 10-year warranty should be weighed against per-watt quotes from your installer. Request at least three quotes to ensure you are getting competitive pricing for this tier of panel.
For hot climates, the temperature coefficient of -0.28%/°C is excellent. This is better than the typical range of -0.30% to -0.40%/°C, meaning the Series 7 545W retains more output on scorching summer days, a significant advantage in states like Arizona, Texas, and Florida. Overall, the First Solar Series 7 545W can be a reasonable choice depending on your budget and performance requirements.
Real-World Performance
In real-world conditions, the First Solar Series 7 545W delivers consistent energy production shaped by its -0.28%/°C temperature coefficient. On a hot summer day when panel surface temperatures reach 65°C (40°C above STC), the Series 7 545W loses approximately 11.2% of rated output — better than PERC panels that lose 13-14% under the same conditions. Over a full year in a typical US location, expect annual specific yield of 1,400-1,700 kWh per kW installed, depending on location, tilt, and shading. The 1.5% first-year degradation settles into 0.5% annual degradation thereafter; after 25 years the Series 7 545W should still produce approximately 86.5% of its original rating. The 144 half-cut cells provide improved shade tolerance compared to full-cell designs — when one cell is shaded, only one sub-string is affected rather than an entire string, limiting production losses to approximately one-third of the panel rather than one-half.
Who Should Buy the First Solar Series 7 545W?
System Design Tips
For commercial string inverter systems, the First Solar Series 7 545W's Voc of 230.5V allows longer string lengths — up to 4 panels per string on 1000V commercial inverters. The Isc of 3.05A requires appropriately rated combiners and conductors — use 10 AWG or larger for runs over 50 feet. Pair with commercial string inverters like SMA Sunny Tripower X, Huawei SUN2000, or Sungrow SG series. The 2520×1244mm footprint (3.13 m²) requires appropriate row spacing to avoid inter-row shading — calculate based on your latitude and winter solstice sun angle. At 38 kg, verify racking load capacity before installation.
Price Estimate
The First Solar Series 7 545W is sold through commercial and utility distribution channels. First Solar pricing varies by distributor and order volume. For a 19-panel system (10.4 kW DC), total installed cost including panels, inverter, racking, wiring, permitting, and labor typically runs $1.50-2.50/W, or approximately $20,710-$25,888 before the 30% federal ITC. After ITC: approximately $14,497-$18,121. Domestic content bonus credits under IRA may reduce costs further.
How the First Solar Series 7 545W Compares
| Model | Wattage | Efficiency | W/sq ft | Warranty | Snow Load | Cell Type |
|---|---|---|---|---|---|---|
| First Solar Series 7 545W (this panel) | 545W | 19.8% | 16.2 | 10 yrs | 5400 Pa | CdTe (Cadmium Telluride) |
| Phono Solar DrivenStar 545W | 545W | 21.1% | 19.6 | 12 yrs | 5400 Pa | PERC Mono |
| Waaree WS-545 Bifacial | 545W | 21.2% | 19.6 | 12 yrs | 5400 Pa | TOPCon N-type Bifacial |
| LONGi Hi-MO 6 Scientist 550W | 550W | 22% | 21.4 | 12 yrs | 5400 Pa | PERC Mono |
Compare This Panel
Installation & Compatibility
System Voltage & String Sizing
- Open Circuit Voltage (Voc)
- 230.5V
- Max Power Voltage (Vmp)
- 190V
- Short Circuit Current (Isc)
- 3.05A
- Max Power Current (Imp)
- 2.87A
- Max Panels per String (600V)
- 2 panels
Based on NEC 600V residential limit. Actual string sizing should account for cold-temperature Voc rise. Consult your installer or use a string sizing tool for your specific location.
Mounting Requirements
- Dimensions
- 2520 x 1244 x 49 mm
- Weight
- 38 kg (83.8 lbs)
- Area per Panel
- 33.7 sq ft
- Weight per sq ft
- 2.5 lbs/sq ft
Recommended Inverter Types
- - Microinverters: Ideal for shaded roofs or complex layouts. Match to panels rated 545W+.
- - String Inverters: Cost-effective for unshaded arrays. Ensure MPPT range covers 190V.
- - Hybrid Inverters: Best if adding battery storage. Check DC input specs match panel Voc of 230.5V.
Frequently Asked Questions
How efficient is the First Solar Series 7 545W compared to other panels?
The Series 7 545W achieves 19.8% module efficiency, which is standard for PERC residential panels. PERC panels typically range from 20.0% to 21.8%, and the Series 7 545W delivers standard performance within that range. Higher efficiency means more watts per square foot of roof space.
What is the warranty on the First Solar Series 7 545W?
First Solar provides a 10-year product warranty covering manufacturing defects and a 30-year performance warranty guaranteeing output levels. The performance warranty typically starts at 98.5% after year 1 and degrades by 0.5% per year, guaranteeing approximately 86.5% output at year 25. The product warranty is in line with industry standards.
How many First Solar Series 7 545W panels do I need for my home?
For a typical US home using 10,000 kWh per year, you need approximately 19 panels (10.4 kW system) assuming 4-5 peak sun hours per day. This varies significantly by location — homes in Arizona may need 16-18 panels while homes in the Pacific Northwest may need 21-23 panels. Your installer will calculate the exact number based on your utility bills, roof orientation, shading, and local solar resource.
What is the efficiency of the First Solar Series 7 545W?
The First Solar Series 7 545W achieves 19.8% module efficiency using CdTe (Cadmium Telluride) cell technology. This is around the industry average for residential solar panels in 2026.
What warranty does the First Solar Series 7 545W include?
It comes with a 10-year product warranty and a 30-year performance warranty guaranteeing output at approximately 84.0% of rated power at the end of the warranty period.
How does the First Solar Series 7 545W perform in hot weather?
With a temperature coefficient of -0.28%/°C, the Series 7 545W handles heat well with minimal power loss. Every degree above 25°C reduces output by 0.28%.
What size system can I build with the First Solar Series 7 545W?
At 545W per panel, you would need approximately 15 panels for an 8 kW system or 19 panels for a 10 kW system. Each panel measures 2520 x 1244 mm (33.7 sq ft).
What inverter is best with the First Solar Series 7 545W?
The First Solar Series 7 545W works well with both string inverters and microinverters. For string inverters, choose one with a maximum input voltage above 230.5V and an MPPT voltage range that covers 190V. Microinverters rated for 545W+ panels are also an excellent choice, offering panel-level monitoring and shade tolerance. Popular options include Enphase IQ8 series microinverters and SolarEdge string inverters with power optimizers.
How long will the First Solar Series 7 545W last?
The First Solar Series 7 545W is built to last well beyond its 30-year performance warranty. With first-year degradation of 1.5% and annual degradation of 0.5% thereafter, the panel will still produce approximately 84.0% of its rated power after 30 years. Most modern solar panels continue generating useful power for 30-40 years, though output gradually decreases over time.
Is the First Solar Series 7 545W good for Arizona and other sunny states?
Yes, the First Solar Series 7 545W is an excellent choice for hot, sunny states like Arizona, Nevada, and Texas. Its temperature coefficient of -0.28%/°C is better than the industry average of -0.35%/°C, meaning it retains more power output on hot days. Higher sun exposure in these states means more total energy production throughout the year, often offsetting any heat-related losses.
Is the First Solar Series 7 545W worth the money?
The First Solar Series 7 545W delivers 19.8% efficiency, which is below the industry average of ~21%. Combined with a standard 10-year product warranty and 30-year performance guarantee, it offers reasonable value for homeowners seeking reliable solar generation.
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Last updated: February 2026