By pressing 1 you only confirmed that you were a human which will make you a target for other telemarketers as they now know they have a legit number to spam. NEVER press anything. Just hang up or don't answer.
Its funny because another number has called me using the same tactic but the pitch was not renewable energy but instead some type of new pain medication.
Also if I had a penny for everyone that complains they are on the DNC list and still get these calls I would be rich. Just like everything else government does, the DNC list is a big pile of crap and only provides scammers with a source for numbers, not to mention political ads, which are exempt from the DNC list.