Segment Solar — US
SG 390W B Ultra
The Segment Solar SG 390W B Ultra is a 390W N-Type TOPCon solar panel with 19.5% efficiency. Made in US. Backed by a 30-year warranty.
Standard Tier🇺🇸 Domestic Content Bonus Eligible
390W
Wattage
19.5%
Efficiency
N-Type TOPCon
Cell Type
30 years
Warranty
Full Specifications
- Brand
- Segment Solar
- Model
- SG 390W B Ultra
- Series
- SG
- Wattage
- 390W
- Module Efficiency
- 19.5%
- Cell Type
- N-Type TOPCon
- Dimensions
- 65-67" x 39-40"
- Weight
- 44 lbs
- Warranty
- 30 years
- Est. Price Per Watt
- $2.45
- Est. 7kW System Cost
- $17,150
- Est. 10kW System Cost
- $24,500
- Temperature Coefficient
- -0.25%/°C
- Bifacial
- No
- Origin
- US
- FEOC Status
- pass
Other Segment Solar Panels
| Model | Wattage | Efficiency | Cell | $/W |
|---|---|---|---|---|
| SG 440W D | 440W | 21.2% | PERC | $2.88 |
| SG 435W C All-Black | 435W | 21% | N-Type TOPCon | $2.83 |
| SG 430W E Pro | 430W | 20.8% | N-Type TOPCon | $2.78 |
| SG 425W B BF | 425W | 20.7% | PERC | $2.75 |
| SG 420W A HC | 420W | 20.5% | N-Type TOPCon | $2.70 |
Similar Wattage Panels (Competitors)
| Panel | Wattage | Efficiency | $/W |
|---|---|---|---|
| Panasonic HIT 420W D Plus | 420W | 22.3% | $4.08 |
| Panasonic HIT 420W A Ultra | 420W | 22.3% | $4.08 |
| SunPower Maxeon 420W B Silver | 420W | 22.2% | $4.21 |
| Maxeon 3-42 HC | 420W | 22.1% | $3.98 |
Frequently Asked Questions
How much does a 390W Segment Solar SG 390W B Ultra cost?
The Segment Solar SG 390W B Ultra costs approximately $956 per panel ($$2.45/W). A typical 7kW system using this panel would cost around $17,150 before incentives.
⚠ The 30% federal solar tax credit has ended — Section 25D expired December 31, 2025, and the Section 48E construction-start deadline passed 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 Segment Solar SG 390W B Ultra a good solar panel?
The Segment Solar SG 390W B Ultra has 19.5% efficiency and a 30 years warranty, placing it in the standard 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 Segment Solar SG 390W B Ultra panels do I need?
For a typical 7kW residential system, you'd need approximately 18 panels. For a 10kW system, plan for about 26 panels. The exact number depends on your roof space, energy usage, and local sun hours.