Cool-roof technologies will be broadly implemented at the Department of Energy and other federal buildings and facilities, under a series of initiatives announced by DOE Secretary Steven Chu.
Chu, a longtime proponent of cool-roof technologies, announced the initiatives Monday (July 19). Cool roofs use lighter-colored roofing surfaces or special coatings to reflect more of the sun’s heat, helping improve building efficiency by reducing cooling costs and offsetting carbon emissions. The federal government is the nation’s largest consumer of energy.
Chu and President Obama have long advocated the federal government’s playing a leading role in moving the nation toward a more sustainable future.
Under Obama’s Executive Order on Sustainability, the federal government has committed to reducing its greenhouse gas emissions 28 percent by 2020. The new DOE initiative is part of that effort.
Under the plan, Chu has directed DOE to install cool roofs when constructing new roofs or replacing old ones, “unless determined uneconomical by a life-cycle cost analysis,” according to Chu’s memorandum on the initiative. New roofs are to have a thermal resistance of at least R-30, Chu directed.
"Cool roofs are one of the quickest and lowest-cost ways we can reduce our global carbon emissions and begin the hard work of slowing climate change," Chu said in a statement. "By demonstrating the benefits of cool roofs on our facilities, the federal government can lead the nation toward more sustainable building practices, while reducing the federal carbon footprint and saving money for taxpayers."
Chu has also issued a letter to the heads of other federal agencies, encouraging them to take similar steps at their facilities. To offer additional support, DOE’s Energy Efficiency & Renewable Energy Building Technologies Program has released its Guidelines for Selecting Cool Roofs, which provides technical assistance on types of roofing materials and how to select the roof that will work best on a specific facility.
The energy benefits of cool roofs extend beyond the individual building, scientists have said. Roofs and road pavement cover 50 to 65 percent of urban areas. Because they absorb so much heat, dark-colored roofs and roadways create what is called an "urban heat island effect," where a city is significantly warmer than its surrounding rural areas. Cool roofs significantly reduce the heat island effect and improve air quality by reducing emissions.
A recent study by researchers at Lawrence Berkeley National Laboratory (LBNL) found that using cool roofs and cool pavements in cities around the world could help reduce the demand for air conditioning, cool entire cities, and potentially cancel the heating effect of up to two years of worldwide carbon dioxide emissions.
DOE is also expanding its research activity for cool roofs. That effort includes developing advanced testing protocols, conducting urban heat island analyses, and undertaking studies to further quantify the direct global cooling benefits associated with cool surfaces.
The department also anticipates awarding new projects to develop higher-performing, innovative roofing materials under its Small Business Innovation Research grant program.
The National Nuclear Security Administration (NNSA), an agency within DOE, has already installed more than two million square feet of cool and white roofs at NNSA sites across the country. Through its Roof Asset Management Program (RAMP), NNSA currently saves an average of $500,000 a year in energy costs and expects to save more than $10 million over the next 15 years, according to DOE. Overall, NNSA has reduced building heating and cooling costs by an average of 70 percent annually on reroofed areas by installing cool roofs and increasing insulation, the agency said.
Design will begin this summer on cool roof replacements at DOE headquarters in Washington, D.C. Projects are also underway at Idaho National Laboratory in Idaho Falls and Brookhaven National Laboratory in Upton, N.Y.
DOE has also begun exploring international opportunities to provide technical support to partnering nations. International activities include tracking the deployment of cool roofs on public- and private-sector buildings, sharing best practices, and developing tools to better measure and communicate the effectiveness of cool roofs, the agency said.