After a decade on Beacon Hill, Pittsfield state Senator Ben Downing will have a new job this winter, as vice-president of a Boston-based solar firm.

Downing chairs the Senate committee that oversees energy, and recently has played a major role in negotiating legislation on solar and renewable energy.

Now, he’s joining that industry. Downing said part of his new job with the company Nextamp will be to help develop business outside of Massachusetts. And he said his legislative experience will help him.

“I’ve been lucky to see the ingredients that are necessary for us to succeed,” Downing said. “That doesn’t mean we’ve been perfect by any means, but I think I’ve been able to learn a lot of those lessons, and that’s in no small part thanks to the partners I’ve had the real honor of working with.”

Downing announced earlier this year he would not be running for a sixth term. Fellow Democrat Adam Hinds, who Downing endorsed, was elected last week and will take over the Senate seat in January.