Green Roofs work well in combination with the use of solar panels. This applies to solar thermal heating and solar power systems.
The main advantages of this combination are: easy installation of solar unit; reliable stability of solar units from load of the Green Roof build up and higher efficiency of the Photovoltaic-module due to the cooling effect of the Green Roof.
On roofs with solar panels, only extensive vegetation can be installed. The solar units have to be installed above the vegetation level so that the panels are not shaded. Special frames of aluminium or robinia are made in order to put the panels above the vegetation level. Earlier the solar units were mounted on concrete bases or slabs and partially filled with gravel; however, they are now mounted on framework which is fixed to plastic boards. The profiled plastic boards are covered with substrate and allow rain water to drain through; thus, allowing plants to grow underneath the solar panels. With the solar panels mounted on the plastic boards the load distribution is spread over a large area and prevents the roof construction from being damaged by point loads.