Marvel's latest "Avengers" movie has been filming in Atlanta. It's headquartered at Pinewood Studios in Fayette County and has done some location work as well . Shooting a massive blockbuster is a huge, time-consuming job but stars Mark Ruffalo, Scarlett Johansson and Chris Hemsworth made space for a little side hustle.

The stars are modeling limited-edition T-shirts that benefit The Solutions Project. It funds projects leading to clean energy and a sustainable future. Learn more here.

MYAJC: Where Marvel stars like to hang out in Atlanta

It's not the first time Avengers cast members have lent their talents to a cause while in Atlanta. Last month, the crew helped raise at least $500,000 for hurricane recovery efforts in Puerto Rico at a live reading of "Our Town" at the Fox Theatre.

Johansson came up with the idea and Evans, Ruffalo, Jeremy Renner and Robert Downey Jr. eagerly joined the effort. Atlanta's Tony-winning director Kenny Leon served as director.

“I knew I could count on you, Atlanta,” Johansson said that night. “We love to shoot here. It’s a very inspiring city, an incredibly inspiring community.”

In September, Ruffalo and Evans paused to honor those working to make Atlanta eco-friendlier during ATL100 , city-wide campaign highlights efforts to embrace renewable energy solutions.

“We can do amazing things. We have the technology to do it,” Ruffalo said during the kickoff at the Plaza Theatre. The wind is in our sails economically, and it just takes us going out to the world and telling everybody the good news. We don’t need fossil fuels anymore. Clean energy from wind, water and sun is the fastest way to our freedom. Whoever controls your energy controls your life (and) controls your destiny. This is how way we take back our destiny, by giving energy to each and every community and letting them make, store, and sell their own energy as they see fit.”