Watt Reduction Factor 

Impact analysis of geometry on potential incident energy

The Watt Reduction Factor extension calculates for a surface the ratio of the solar irradiance (W/m²) to the theoretical irradiance of an identical but virtual and isolated surface without surrounding surfaces.

The Watt Reduction Factor can be interpreted as the normalization of a standard Watt calculation by the maximum reachable with the local climate.

A 0% sensor means that it receives no light.
A 100% sensor means that it receives the maximum light energy possible at this location due to climate.

This indicator makes it possible to compare surfaces and to interpret their performance according to their geometric characteristics, minimizing the influence of climate and orientation.

This indicator is useful for performance optimization of a building, especially for low-energy houses.