What are BioSolar Roofs and How Do They Benefit?August 1, 2017
Guest blog post from Hosta Consulting. Image credit: Dusty Gedge.
Combining solar panels with green roofs can bring some amazing benefits. These ‘Biosolar’ roofs bring together the energy-generating capability of solar PV arrays and the water-storing, habitat creating benefits of green roof systems.
Ironically, on long, hot, summer days, solar PV panels can actually become less efficient; temperature plays an important part in their efficiency. Some reports suggest heat can reduce output efficiency by as much as 10-25% in certain cases. Research has shown that compared to flat un-vegetated gravel roofs, green roofs can be up to 21ºc cooler (Kaiser 1981), clearly providing some benefits for PV arrays.
Additionally, as the solar PV panels create shading on the roof surface, new habitats are created allowing a large range of species to be utilised on the roof, bringing ecological benefits. Three different micro-habitats can be created; the first one ideal for growing sedum, the second is a more moist area, as the PV panels shed water onto the green roof when it rains, and the third is the dry shade where the panels cover the green roof. Each of these areas can be used to attract an abundance of wildlife that would not otherwise be a part of the city or region.
There are additional technical advantages to Biosolar roofs; due to the integrated nature of the two systems, the green roof system can be used as ballast for the PV panels, meaning that they can be fixed to the roof without any risk of penetrating waterproof membranes or the structure of the roof itself.
Installation of green roofs increases the lifetime of roof surfaces protecting them from UV and other environmental damage. As the green roof is a living system it is a lot easier to maintain without disrupting energy generation when the roof system requires maintenance, simply replanting, or sowing seeds around the panels.
Biosolar roofs provide an opportunity to maximise roof spaces to generate electricity, increase the lifetime of the roof, and with thoughtful planting, provide a habitat for urban flora and fauna essential for future healthy cities.
Categorised in: EvoEnergy News