This weekend, Houston’s NRG Stadium will light up with the spectacle of Super Bowl LI, and millions across the country will be tuning in to watch the Patriots play the Falcons.

Typically, the energy for a sports event like this comes from the players. But a few years ago, the conversation turned to actual electricity, thanks to a 22-minute partial power outage during Super Bowl XLVII.

Observers were left scratching their heads over what caused the blackout. Some speculated it was Beyoncé’s lights-out halftime. Others pointed to flaws in the newly installed electrical system.

The moment highlighted (or low-lighted) the need for reliable power at NFL stadiums. And that means more renewable energy. Houston’s NRG Stadium, where this year’s Super Bowl will be held, gets power from 600 solar panels. It’s also one of the first stadiums to use only LEDs to light up the playing field. The LEDs use 60 percent less energy than the previous system.

NRG Stadium in Houston. Source: Ed Schipul

This year, NRG will provide renewable energy credits for all event venues associated with the Super Bowl, including the George R. Brown Convention Center and the hotels where the teams stay. The host committee is instituting other sustainability measures, too, like recovering leftover food from Super Bowl events. The Houston Food Bank and other nonprofits will distribute the food to local shelters, pantries and soup kitchens. The NFL also plans to collect and donate as many left over materials as possible after the game, including building supplies, fabric, signs and decorations. Local organizations will repurpose or recycle them, to keep them out of landfills.

The trend towards sustainability isn’t just a postseason phenomenon. In recent years, the NFL has become an unlikely champion of renewable energy, teaming up with the Environmental Protection Agency, Natural Resources Defense Council and other environmental organizations to monitor its clean energy initiatives.

Lincoln Financial Field. Source: DLR Group

In 2015, nearly one-third of NFL teams played or trained at solar-equipped facilities, according to the Solar Energy Industries Association.

That figure includes a couple of standouts, like Gillette Stadium in Foxborough, Massachucets. The complex boasts some 3,000 solar panels — enough to power office buildings and stadium lights on days without a game. Philadelphia’s Lincoln Financial Field features 11,000 solar panels and 14 wind turbines, the most of any stadium.

Other stadiums have seen similar gains in efficiency. San Francisco’s Levi’s Stadium was the first to earn LEED Gold certification and has the first “living roof” in the NFL. The brand new US Bank Stadium, which opened in Minneapolis in September, uses substantially less energy than its predecessor, the Metrodome, thanks to conservation measures. Other venues are building charging stations for electric cars and developing innovative ways to recycle waste.

The “living roof” atop Levi Stadium. Source: Hydrotech

The NFL’s commitment to sustainability is showing fans, teams and staff the environmental and economic benefits of sustainability. Leonard Bonacci, Vice President of Event Operations and Event Services for the Eagles, and a committed Republican from a coal-rich state, said he was won over by the financial advantages of moving to clean energy. He’s now getting the ball rolling on other conservation initiatives.

“It’s just like a game of football,” Bonacci told The Guardian. “Incrementally, you move the ball down the field.”

Bridgette Burkholder and Laura A. Shepard write for Nexus Media, a syndicated newswire covering climate, energy, policy, art and culture. You can follow them at @bridgette_ck and @LAShepard221.