Novel PV System Design for Green Rooftops from France
Sourced from PV Magazine
French startup Ecovégétal has developed a PV system configuration that uses vegetation to reduce the operating temperature of the modules. It says the presence of certain plants on a flat rooftop can even serve as a bulwark against the risk of fire.
France's Ecovégétal has released Héliovert, a PV system for green rooftops that combines solar power generation and urban gardening.
“The idea of exploiting the synergy between these two technologies came from a study currently being carried out by Cerema, a French public agency for developing public expertise in the fields of urban planning, in Nancy,” Pierre Georgel, the CEO and founder of the green roof specialist, told pv magazine France.
The new system is the result of several years of research under the PROOF project, which aims to assess the energy contribution of a green rooftop to the electrical efficiency of a solar panel.
“The first results show an increase in electricity production yields of 8 to 10% thanks to the presence of vegetation which acts as a thermal regulator under the photovoltaic panels,” said Georgel. “But it goes much further than putting lawn on a roof. It is indeed the vegetation that serves as ballast for the solar panel fixing system.”
In the proposed system configuration, drains known as XD20, DK20, or equivalent are laid over the entire surface of the roof and serve as an anti-root sealing system and for the retention of rainwater at a rate of 7 liters per square meter. A recycled plastic slab is installed on top.