TechnicalUp to date · Jan 15, 2026
Power Density
The watts generated per unit area of a solar panel, calculated as panel wattage divided by area. Higher efficiency panels have greater power density, meaning fewer panels for the same output.
Why It Matters
When roof space is limited, higher power density panels (400W+ in standard residential size) maximize total system capacity.
Related Terms
Module Efficiency
The percentage of sunlight that a solar panel converts into electricity. Modern panels range from 15-22% efficient.
Kilowatt-Peak (kWp)
The maximum output of a solar system under Standard Test Conditions (STC: 1000 W/m² irradiance, 25°C cell temperature). This is the nominal system size quoted by installers.