Finsbury Park was a project that gave us the chance to demonstrate how green roofs and solar panels can work together on a roof to improve the performance of both.
We installed both wildflower and sedum plugs, grown and hardened in our nursery into our biodiverse substrate mix. By installing a range of vegetation we were able to start to increase the biodiversity of the roof. The addition of solar panels also helped to increase the biodiversity.
Solar panels on a roof will create shaded areas beneath each panel, which causes a microclimate to be formed. This allows different species of plants to populate the shady, damp areas and the sunny, drier zones, increasing the diversity of life on the roof. This range of plant life will attract a wider variety of wildlife to the area compared with a green roof without solar panels.
The effect of having a green roof under the solar panels is actually to make them more efficient. Green roofs have a cooling effect, reducing the temperature of a roof by a few degrees compared to a standard black or white roof. As the electricity generated by solar panels is reduced as they heat up, PV panels installed over a green roof actually produce more electricity in the same conditions that panels installed on a conventional roof would.
For more information please see our article on green roofs and solar panels.