Going green with biosolar

By Emma Peterson. 

Looking for a way to make a roof more sustainable? Consider combining a green roof with a solar set up!  

There are a variety of ways to make a roof more sustainable, such as reflective roof coatings, living roofs and solar panels. These different strategies can lower a building’s energy usage (for example, a cool roof coating lowers the need for air conditioning by reflecting thermal heat) and make previously unused space into a valuable asset. But how do you know which roofing system will create the most environmental benefits for the roof and the area it is in? The research shows that you using more than one system! 

What is a biosolar roofing system? 

At its core, a biosolar roof is simply a flat roof that features both an extensive green roof (lighter and low-growing mediums) and a solar roofing system. It can be arranged in a variety of ways, with the panels being installed either above the greenery or alongside it. The reasoning behind installing both of these systems is that they have a symbiotic relationship.  

Solar panels are designed to absorb and process sunlight. A byproduct of this is that they often collect heat from the light. An article from Greenscape explains, “As they rise above about 25 degrees Celsius [77°F], their efficiency decreases quickly.” But, when you use these panels in tandem with a green roof, the naturally cooling effects of the vegetation will not only cool the ambient environment (which helps combat things like the Urban Heat Island effect), but also the panels!  

And this symbiotic relationship is a two-way street. Greenscape reports, “[By having panels on the roof] a biosolar system creates a diversity in the conditions across the roof. Some portions will be exposed, and others shaded. Water runoff from the panels will collect, creating a mix of damper and drier areas. This creates what is called a habitat mosaic, in which a wider variety of flora can flourish.” 

And this is not just a theoretical symbiotic relationship, biosolar roofs have been scientifically tested and proven to be more powerful than the sum of their parts. A study by Peter Irga, Eamonn Wooster, Fraser R Torpy and Jack Rojahn reports that, “The [studied] green roof supported much more biodiversity, as one might expect. By reducing average maximum temperatures by about 8℃ (46°F), it increased solar generation by as much as 107% during peak periods. And while some plant species outperformed others, the vegetation flourished.” 

Beyond environmental benefits  

At the end of the day, research shows that combining solar panels with green roofing is a powerful way to make a roof more environmentally friendly and sustainable. But those are not the only benefits that come from installing biosolar!  

Elevate reports, “While the initial investment may be higher than a traditional flat roof, the combination of energy savings, reduced stormwater fees and potential incentives can result in a faster payback period. Additionally, a biosolar roof can contribute to increasing the property’s value.” Ultimately, biosolar roofing is a great example of how innovative design can create a greener future without sacrificing building integrity, durability or aesthetics.  

Original image source: Elevate