B.W.
This is probably bad advice, but why don't you give him 1/2 piece of gum instead? And teach him that's it's to chew on, then spit out to get another piece. If he had older siblings, he might be chewing gum with them, anyway. (we protect the oldest, and the younger ones get to learn from their older siblings, not just from us)
Sucking on things, chewing on things, are pretty normal behavior. It doesn't end when the bottle goes away. If he knaws on toys that are soft and pliable (kind of like teething toys), there really shouldn't be a problem. I would just try to keep him safe, and keep him from chewing on things you want to protect from him and protect him from. I suspect the behavior will disappear over time -- but I'm saying this knowing that whenever I have a pen in my hand, I chew on the end of it !
There are probably some things you can spray on them that would make them taste HORRIBLE -- some are even organic, like cayenne pepper or something -- it works keeping animals from plants ( I put cayenne pepper on bulbs when I plant them, so skunks and deer don't dig them up), so if there's something that works in the garden, that isn't toxic or too strong, it would make the electric cords taste hideous and he might not want them in his mouth ! Just be extremely careful with what you use if you resort to that kind of routine.
But in all honesty, I think it'll pass . . . :-)