Solar & Outdoor
Quantify shading effectiveness
The Watt Reduction Factor (WRF) measures how much a shading device or nearby obstruction reduces incident solar energy on a surface relative to an unobstructed reference case. A WRF of 0% means no shading; 100% means total blockage.
WRF normalises the result by local climate, giving a meaningful comparison across projects and climates. It is particularly useful for comparing shading strategies and optimising facade design for energy performance.
- Ratio of obstructed to unobstructed solar irradiation
- Climate-normalised result for cross-project comparison
- Compare shading devices, overhangs, and fins
- Useful for facade optimisation and energy performance targets
- Works on any surface including glazing and opaque panels
