User blog comment:ChishioKunrin/RWBY 3 Livestream points/@comment-26512661-20160213000012/@comment-4010415-20160213015127

"getting hurt or angry" No, her anger has nothing to do with her Semblance giving her power. She just has a habit of using her Semblance when she's angry because, like they said in this stream, Yang has a habit of relying on her Semblance too much.

She can store the energy she gains to use later.