Committed to the cause

The Boston GreenFest puts its mission where its mouth is. To celebrate environmental progress, folks at this three-day festival will attempt to power one of three stages with solar energy and another with pedal power. Through art, music, fashion, films, discussion, cooking demos, and exhibits, we’ll all learn how to give a green light to sustainability. More than 40 acts reflecting Boston’s diverse cultures include tonight’s lineup of Mr. Lif, Tem Blessed, and the Click 5. Children will dig puppet shows, stories, and performers in the kid-friendly area. Tonight from 5-10 p.m. (Aug. 21 and 22 from 10 a.m.-10 p.m.). Free. Boston City Hall Plaza. 617-477-4840. www.bostongreenfest.org