A residence hall at the University of North Carolina beat more than a dozen competitors to win a U.S. Environmental Protection Agency contest to see which building could save the most energy.

The EPA announced Tuesday that on the university’s Chapel Hill campus slashed energy use by nearly 36 percent in one year. That was best in a field of 14 buildings across the country chosen from nearly 200 that wanted to join the EPA’s first

Students and staff involved in the effort called themselves the “Carolina Watt-Busters.”

“We want to make significant and sustainable improvements in how we occupy, maintain and operate Morrison Dormitory,” said Chris M. Martin Jr., director of energy management, when the Carolina Watt Busters entered the competition.

Morrison Hall stands 10 stories tall, includes 217,552 square feet of space and has a capacity of 850 residents. Renovations in 2007 added central heating and air conditioning and installation of solar panels for heating water.

The dorm is home to students who want to participate in programs on energy and sustainability.

The building reduced its energy use further over the year ending August 31 by using a computer touch-screen monitor in the lobby that helped everyone keep track of energy consumption. Competitions between floors in the dorm challenged students to see who could save the most energy by turning off lights and computers, and reminders were posted in elevators, bathrooms, and common areas.

Second place went to a Sears store in Glen Burnie, Md., that reduced energy use by 32 percent. A J.C. Penney store in Orange, Calif., that saved 28 percent was third.

The dormitory beat a backyard rival. Tucker Residence Hall at North Carolina State University in Raleigh, about 25 miles east, finished eighth.

The contest monitored the energy use of the participating buildings with an online tracking tool. Together, the buildings saved more than $950,000 in utility bills and cut carbon dioxide emissions by an amount equal to a year’s worth of electricity for nearly 600 homes.

Commercial buildings account for nearly 20 percent of total U.S. greenhouse gas emissions, and about 30 percent of the energy used in them is wasted, the EPA said.

The top 14 in rankings

Rankings in the U.S. Environmental Protection Agency’s National Building Competition, with location, type of building, and percentage of energy saved:

1. Morrison Residence Hall at University of North Carolina, Chapel Hill, N.C.; dormitory, 35.7 percent.
2. Sears Glen Burnie, Glen Burnie, Md.; retail store, 31.7 percent.
3. J.C. Penney, Orange, Calif.; retail store, 28.4 percent.
4. 1525 Wilson Boulevard, Arlington, Va.; office building, 28 percent.
5. 522 Fifth Avenue, New York, N.Y.; office building, 18.1 percent.
6. Solon Family Health Center, Solon, Ohio; medical office building, 13.9 percent.
7. Crystal River Elementary School Carbondale, Colo.; K-12 school, 12.2 percent.
8. Tucker Residence Hall at North Carolina State University, Raleigh, N.C.; dormitory, 10.3 percent.
9. Courtyard by Marriott San Diego Downtown; hotel, 8.6 percent.
10. Maplewood Mall, Maplewood, Minn.; enclosed shopping mall, 6.7 percent.
11. Memorial Arts Building at Woodruff Arts Center, Atlanta; museum, 5.7 percent.
12. Van Holten Primary School, Bridgewater, N.J.; K-12 school, 5.3 percent.
13. Sheraton Austin Hotel, Austin, Texas; hotel, 1.9 percent.
14. Virginia Beach Convention Center, Virginia Beach, Va.; convention center, 1.5 percent.

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