Silfab Solar — US/Canada
SIL Prime 400W B Plus
The Silfab Solar SIL Prime 400W B Plus is a 400W N-Type TOPCon solar panel with 20.2% efficiency. Backed by a 25-year warranty.
Premium Tier🇺🇸 Domestic Content Bonus EligibleBifacial
400W
Wattage
20.2%
Efficiency
N-Type TOPCon
Cell Type
25 years
Warranty
Full Specifications
- Brand
- Silfab Solar
- Model
- SIL Prime 400W B Plus
- Series
- SIL Prime
- Wattage
- 400W
- Module Efficiency
- 20.2%
- Cell Type
- N-Type TOPCon
- Dimensions
- 66-80" x 39-41"
- Weight
- 46 lbs
- Warranty
- 25 years
- Est. Price Per Watt
- $2.81
- Est. 7kW System Cost
- $19,670
- Est. 10kW System Cost
- $28,100
- Temperature Coefficient
- -0.25%/°C
- Bifacial
- Yes
- Origin
- US/Canada
- FEOC Status
- pass
Other Silfab Solar Panels
| Model | Wattage | Efficiency | Cell | $/W |
|---|---|---|---|---|
| SIL 455W E Pro | 455W | 22% | PERC | $3.35 |
| SIL-N 455W E Pro | 455W | 22% | PERC | $3.35 |
| SIL Prime 455W E Pro | 455W | 22% | PERC | $3.35 |
| SIL 445W D Plus | 445W | 21.7% | N-Type TOPCon | $3.26 |
| SIL-N 445W D Plus | 445W | 21.7% | N-Type TOPCon | $3.26 |
Similar Wattage Panels (Competitors)
| Panel | Wattage | Efficiency | $/W |
|---|---|---|---|
| SunPower Maxeon 430W E Max | 430W | 22.6% | $4.38 |
| SunPower Maxeon 430W B All-Black | 430W | 22.6% | $4.38 |
| SunPower Maxeon 430W C Black | 430W | 22.6% | $4.38 |
| SunPower Performance 430W E Max | 430W | 22.6% | $4.38 |
Frequently Asked Questions
How much does a 400W Silfab Solar SIL Prime 400W B Plus cost?
The Silfab Solar SIL Prime 400W B Plus costs approximately $1124 per panel ($$2.81/W). A typical 7kW system using this panel would cost around $19,670 before incentives.
⚠ The 30% Federal Solar Tax Credit (48E/ITC) expired July 4, 2026.
Selecting 30% ITC assumes you began construction before this deadline. Most new purchases no longer qualify.Learn about your options after the deadline →
Is the Silfab Solar SIL Prime 400W B Plus a good solar panel?
The Silfab Solar SIL Prime 400W B Plus has 20.2% efficiency and a 25 years warranty, placing it in the premium tier. This is a solid mid-range panel suitable for most residential installations. It also qualifies for the domestic content bonus under the Inflation Reduction Act.
How many Silfab Solar SIL Prime 400W B Plus panels do I need?
For a typical 7kW residential system, you'd need approximately 18 panels. For a 10kW system, plan for about 25 panels. The exact number depends on your roof space, energy usage, and local sun hours.