Melissa Tobias, National Geographic magazine's My Shot.

In sports, April was a big month, with major arenas that are home to professional basketball and ice hockey teams announcing the receipt of LEED certification, a third-party verification of their green building operations and performance.

The American Airlines Arena in Miami and Philips Arena in Atlanta joined the Washington Nationals Ballpark in Washington, DC and Detroit Lions Headquarters and Training Facility as professional sports facilities that have earned the label "green," according to the U.S. Green Building Council (USGBC), which developed LEED (leadership in energy and environmental design) standards. The arenas house baseball, football, basketball, and ice hockey teams.

Seven other university and private sports facilities, including tracks and gymnasiums, have earned LEED certification. And according to USGBC spokesman Marie Coleman, 139 sporting arenas have applied for LEED certification or are in the process of greening.

To distinguish it as ecofriendly, the American Airlines Arena includes reflective roofing materials, which reduce the need for forced cooling; water-efficient landscaping with drought-resistant plans and efficient "micro" irrigation; and underground parking instead of a heat-trapping asphalt lot.

Nationals Park in Washington, DC, and Medlar Field at Lubrano Park on the campus of Penn State University in State College, Pennsylvania, are considered by many to be the greenest sports venues around. This is because they were built green from the ground up, as opposed to having green features added years after original construction, according to Kevin Reichard, publisher of several websites covering sports facilities, including green roof over concessions, and was built on a previously contaminated site.

Attorney Chuck Greenberg, the president of the State College Spikes, a minor league baseball team that also plays at Medlar Field, has been involved with an effort to get the Pittsburgh Penguins’ new facility to be the first sports facility to earn the second highest LEED rating—gold.

But according to Reichard, despite the fact that some 35 new college and professional sports venues have opened this year, green building has not been a priority for most.

“There isn’t a lot of pressure [to] build green in the industry,” Reichard said. “The Yankees and Mets purposefully passed on the option. There are still a lot of added costs with going green.”

That said, Reichard notes that the biggest sports architecture firm in the world, Populace (formerly HOK Sports, which designed Nationals Ballpark) now has a full-time sustainability coordinator.

The green features of Nationals Park bumped up the price by about $2 million according to HOK Sport architects, but the high-efficiency lighting uses nearly 20 percent less energy, and air-cooled concession refrigeration, versus water-cooled, will save approximately six million gallons of water a year.

Score.

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