Mark Ruffalo was a guest on The Daily Show with Jon Stewart last night. The interview kicked off promoting his latest movie, Infinitely Polar Bear. After a funny debate about a hypothetical battle between Hulk and Superman, Ruffalo took the opportunity to discuss some other things that are on his mind.

Ruffalo, who was been an environmental champion for years, helped to ban fracking in New York state and is a huge advocate of renewable energy. So, he took some time on The Daily Show to talk about his organizations Water Defense and The Solutions Project, and how he is backing Stanford Professor Mark Jacobson in his campaign to ditch fossil fuels and go 100 percent renewable by 2050 in every state in the U.S. The 50-state plan is posted on The Solutions Project website.

Check out the interview here:

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