When Jack Johnson announced this year that his summer tour would yet again give away 100 percent of the proceeds generated, I was left wondering how this was possible. After all, people on a tour independent of the main star attraction need to make a living, to eat, be transported, etc.

Thankfully, CNN was wondering the same thing, and they recently sat down with the artist to find out how fundraising tours are even possible. The interview comes on the heels of Johnson releasing his fifth album, "To the Sea", which, naturally, was recorded in a 100 percent solar-powered studio in Los Angeles.

In the article, Johnson says CD sales (more than 18 million and counting) are what allow fundraising tours to rock out. Everyone still makes a living while playing in various cities — but all of the money generated goes right into green initiatives.

"There's between five and 10 local nonprofit groups that come out to every show, and money from that show goes directly to the groups — a certain percentage of it from that night," Johnson says. "At the end of the whole tour, we take the rest of it and we put it into a foundation. The nice thing with that is it's a perpetual deal, so we give away the interest every year."

The 35-year-old adds that any green organization can apply for a grant at his website, AllAtOnce.org.

"It's actually rewarding to see the tangible things — this amount of instruments are going to this school district — or to see photographs of a garden that got built from some of the funds," he adds.

Check out the rest of the interview over at CNN.

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.