although i haven't been keeping snakes very long, My parents happen to be in the computer industry and I manages to grab one of their extra Ups's (uninteruptible power supply) you just plug it in the wall and then plug your thermostat into it and when the power goes out the ups keeps everything going until the power is restored, their kind of pricy though Im lucky we had an extra, and I would rely on it for more than an hour or two