The solar angle of incidence for noon, 21 March (55 degrees) was used to determine the geometry of the daylighting systems, as detailed in Fig. 1(b). This angle of incidence was considered an intermediate position that accounts for shading during both summer and winter.
Their visual properties and sizing are intended to reflect light into the depth of the room and decrease light levels at the front, in order to balance light distribution and improve visual comfort.
These systems also contribute to save energy consumption through reduced admittance of solar radiation. This is demonstrated in Fig. 2 which has been adapted from a separate study [5] for the same location, and that focused on the energy consumption effect of external lightshelves as horizontal shading devices.
The graph corresponds to a South-facing office with depth 6.7 meters, where applying a lightshelf of 50 and 100 cm decreases energy loads per square