Efficiency Peak in the RockiesThe U.S. government's clean energy research team now works on a campus in the Rocky Mountain foothills that aims to showcase the promise for better buildings. With Colorado's night air and intense sunlight helping to cool, heat and light the space for more than 800 workers, the new $64 million National Renewable Energy Laboratory (NREL) Research Support Facility uses half the energy of a more typical office building."It is, to our knowledge, the world's most efficient building," says Dan Arvizu, the laboratory director.The H-shaped edifice in Golden, Colorado (map) is at the vanguard of an effort by the federal government—the largest single energy consumer in the U.S. economy—to prove that it is possible to use far less power, even with complex and diverse jobs to do. (Related: Overview Story) Following is a collection of U.S. government buildings that exemplify that efficiency drive, in many cases overcoming daunting obstacles with creative design.NREL’s Research Support Facility, opened in June, houses the people who analyze U.S. research data on solar, wind, and other renewables, as well as advances in building energy. They also do the difficult job of moving that technology to commercialization.The building's long sides face north and south, allowing maximum daylight, while concave devices in the window glass reflect sunshine onto the white, highly reflective ceiling to provide diffuse, even light for all the building's workspaces.The ceiling also contains 42 miles (68 km) of plastic tubing, where cool water circulates in summer and warm water in winter. But the radiant cooling and heating gets a big assist from outdoors. Windows open to let in cool night air. For warmth, fans draw air in during the day through a transpired solar collector wall—an innovation developed by NREL's own scientists. The perforated dark metal sheets capture enough solar energy to heat the air as much as 49ºF (9ºC) in the sunshine. Thick, heavy concrete walls and an innovative subterranean thermal labyrinth, or crawl space, beneath the first floor, help regulate the indoor temperature.The building received the highest possible score in the U.S. Green Building Council’s LEED Certification program, and is expected to earn a Platinum rating later this year. But NREL senior engineer Otto van Geet says the building should be considered an "evolutionary" use of proven technologies, rather than a revolutionary facility that will be unique. "Every one of these strategies is very replicable, and many of them are appropriate for all buildings and all locations," he says.—Candace Adorka

Photograph courtesy Patrick H. Corkery, NREL

Pictures: Seven Supergreen U.S. Government Buildings

A subterranean labyrinth in the Rockies, breathing curtain walls by San Francisco Bay, and a Manhattan sky park highlight the U.S. government's drive to cut down its prodigious use of energy.

December 15, 2010