Department of Energy Installs Cool Roof at Capitol HQ
While this story may not get as much play as it would have in July when temperatures in Washington, DC were some of the hottest in memory—and it might even become fodder for conservative media pundits who like to seize upon any cold winter weather as proof global warming is a fraud—but the Department of Energy has completed the transformation of the roof at its Washington, DC headquarters to an energy-efficient white roofing material. The move will reduce the building's energy consumption by 10 to 20 percent. The roof was due for a scheduled replacement so engineers replaced the old black membrane with energy-efficient "cool" roofing material — and they did so at no extra cost to taxpayers.
"The reason we wanted the department of Energy to take the lead in cool roofs is to demonstrate that this really saves money," said Secretary of Energy Steven Chu.
In July, Secretary Chu directed DoE offices to install cool roofs whenever they were replacing an old roof or constructing a new one, providing the energy efficient roofs are cost-effective over their lifetimes, which, in most cases they are. Chu has also recommended to other federal departments that they adopt similar replacement policies. Here is Secretary Chu talking about the Department's new roof and the rationale behind it:
Cool roofs can not only cut a building's energy consumption by 20 percent and they also help reduce the "urban heat island effect," the phenomena that occurs when rooftops and pavements, an area that is up 50-65% of the surface area in a city, absorb tremendous amounts of heat from sunlight. Urban heat islands normally have temperatures that are 2 to 5 degrees warmer than the surrounding areas. The phenomena is particularly noticeable on those long hot summer nights in the city when temperatures don't seem to drop after sunset.
"All of those dark roofs mean that as a nation we’re using a lot more air conditioning than we need to. At least a billion dollars a year in extra power bills," writes Cathy Zoi, Acting Under Secretary of the Department of Energy.
A study on the climatic impacts of cool roofs by researchers at Lawrence Berkeley National Laboratory found that if just over three quarters of our nation’s commercial buildings were updated with cool roofs, the U.S. would save enough energy on air-conditioning to reduce CO2 emissions by about 6 million metric tons each year.