I just asked hubby and he said that's worded poorly.I'll definitely ask when the time comes but I've been under the assumption that the heat source is a required thing- it's also listed as its own item on the "code requirements" section of the coop permit application, it's brought up in this article as a requirement. The one thing I'm missing is talking to someone who actually passed inspections and keeps chickens in the area, and/or someone who works directly with the inspection process. It's one of the specific things I really hope to eventually get in touch with a local about on this forum, to see how they deal with a couple things related to the ordinances I've been looking at!
(That all being said, I haven't actually moved yet. I'm waiting to ask some specific questions to the local inspectors once I'm actually on the property, could have them come over and see the site of the future coop if they need to, etc)
As an electrician, he would take that as if you're going to have electricity and a heater, the electricity has to be wired to the coop and has to be on a dedicated circuit. The heater has to be independent in the coop meaning not sourced from say your home, like in my funny example, the drier vent.