First issue is will this material be suitable for wind speeds of 100 miles per hour?
I live in a coastal city where wind gusts reach that speed and that is "a bad winter storm".
Did they think to look at the mechanical ventilators used on glass houses? These are driven by the thermal expansion of wax (incompressible fluids can exert a very large force)
For the cost of the proposed surface perhaps they should be looking at optimal spacing of solar panels (solar panels have a higher initial cost but have a long term financial benefit as opposed to the alternative roof material). On a tile roof the installation requires an air gap between the panels and the roof, this gap has cooling benefits however panels are often placed edge-to-edge preventing any hot air trapped from escaping.