UCLA Law’s Emmett Center on Climate Change and the Environment released a new report today called Bright Roofs, Big City: Keeping L.A. Cool Through an Aggressive Cool Roof Program. The report is the second Anthony Pritzker Environmental Law and Policy Brief issued by the Center.
Cara Horowitz, the author of the report, used a dataset of Los Angeles rooftops and estimated energy savings the city could achieve simply by using roofing surfaces that “reflect … more of the sun’s light and heat than the average rooftop.” Horowitz concludes that the energy savings we could achieve by switching all roof surfaces to cool roof materials could save $30 million annually in energy costs and could eliminate up to 40 million tons of greenhouse gas emissions on a one time basis. Just to give you some perspective, 40 million tons is equivalent to removing seven million cars from the road for a year and is nearly 80 percent of the city’s total annual emissions. And that’s not all: the use of cool roofs could significantly lower urban temperatures, which are on average higher than surrounding areas because paved areas radiate heat, which would in turn led to less smog and lower air conditioning use.
So why don’t we already have such roofs? Part of the reason is that many people simply don’t know about the benefits of cool roofs materials. And cumbersome permitting requirements can deter consumer participation. The city has taken some important steps to encourage cool roof installation, including funding a cool roof rebate program through the Department of Water and Power and requiring some cool roofing materials for new construction. But the city could do a great deal more, as Cara’s report advises. But you’ll have to read the report to see her important recommendations. You can find it here.