Now, the French Senate has approved a bill that should increase that markedly, requiring parking lots with a minimum of 80 spaces to be covered by solar panels, according to Public Senat.When outdoor parking lots have"technical, safety, architectural, heritage and environmental constraints," they may be exempt.Lots shaded by trees over at least half their area may also escape the requirement, as will parking lots for trucks.Parking lots covered with solar panels are not yet that common, with one of the largest examples being the Belgium Zoo parking lot pictured above.Its 7,000 parking spaces are 70 percent covered by 62,000 overhead solar panels that generate 20 megawatts of peak power — much more than is required for the zoo."