If you want to increase the solar energy generation in vertical solar installations (solar panels aligned along the walls) in buildings. You can do the following things-

1. Optimise the orientation of the panels such as using south-, east-, or west-facing facades.
2. You can also opt for highly efficient solar modules to maximise generation from the same area.
3. Enhancing the reflectivity of surrounding areas, such as using light-colored pavements or walls, further boosts energy capture.