Explanation:
bottom right (vertical fins or louvers shading the window) is the most effective.
* West-facing windows receive strong, low-angle afternoon sun in the summer, which is difficult to shade with horizontal overhangs because the sun's rays come in at a low angle.
* Vertical shading devices (like fins or louvers) placed perpendicular to the window are most effective in blocking low-angle sunlight from the west.
* The top left and top right images show horizontal shading, which works better for south-facing windows but is less effective for west exposures.
* The bottom left shows multiple horizontal fins, which help but still less effective for west-facing windows compared to vertical fins.
According to NCARB ARE 5.0 PPD content on solar shading and passive solar design, vertical shading is preferred for east and west exposures to minimize summer heat gain.