Segment Solar β€” US

SG 405W D Pro

The Segment Solar SG 405W D Pro is a 405W PERC solar panel with 20.0% efficiency. Made in US. Backed by a 25-year warranty.

Standard TierπŸ‡ΊπŸ‡Έ Domestic Content Bonus EligibleBifacial

405W

Wattage

20%

Efficiency

PERC

Cell Type

25 years

Warranty

Full Specifications

Brand
Segment Solar
Model
SG 405W D Pro
Series
SG
Wattage
405W
Module Efficiency
20%
Cell Type
PERC
Dimensions
66-80" x 39-41"
Weight
46 lbs
Warranty
25 years
Est. Price Per Watt
$2.58
Est. 7kW System Cost
$18,060
Est. 10kW System Cost
$25,800
Temperature Coefficient
-0.35%/Β°C
Bifacial
Yes
Origin
US
FEOC Status
pass

Other Segment Solar Panels

ModelWattageEfficiencyCell$/W
SG 440W D440W21.2%PERC$2.88
SG Plus 440W D440W21.2%PERC$2.88
SG Max 440W D440W21.2%PERC$2.88
SG 435W C All-Black435W21%N-Type TOPCon$2.83
SG Plus 435W C All-Black435W21%N-Type TOPCon$2.83

Similar Wattage Panels (Competitors)

PanelWattageEfficiency$/W
SunPower Maxeon 435W A Ultra435W22.7%$4.42
SunPower Performance 435W A Ultra435W22.7%$4.42
SunPower X-Series 435W A Ultra435W22.7%$4.42
SunPower E-Series 435W A Ultra435W22.7%$4.42

Frequently Asked Questions

How much does a 405W Segment Solar SG 405W D Pro cost?
The Segment Solar SG 405W D Pro costs approximately $1045 per panel ($$2.58/W). A typical 7kW system using this panel would cost around $18,060 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 Segment Solar SG 405W D Pro a good solar panel?
The Segment Solar SG 405W D Pro has 20% efficiency and a 25 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 405W D Pro 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.

Written & reviewed by

Jeremy Wolfe β€” Senior Solar Energy Analyst

Jeremy Wolfe is a solar energy analyst specializing in residential photovoltaic economics, federal and state incentive policy, and return-on-investment modeling for homeowners. He leads EnergyTools' solar research program and methodology.

  • 10+ years analyzing residential solar economics and payback modeling
  • Lead researcher for EnergyTools' 50-state solar cost-per-watt database
  • Author of 100+ solar ROI, payback, and incentive analyses

Methodology & data sources:NREL PVWatts, EPA FuelEconomy.gov, state utility commissionsβ€” updated 2026.