Because heat-reflective white roofing can cut power consumption by reducing air-conditioner loads, utilities and some state and local governments have long offered incentives to encourage its use. A recent demonstration project by the Lawrence Berkeley National Laboratory could someday lead to similar programs for light-colored parking lots. According to the LBNL researchers, pavement accounts for 35% to 50% of the surface area in a typical city, and heat-reflecting asphalt can be as much as 40° cooler than conventional paving on a hot, sunny day.