The main issue is that it's a single 120V circuit for everything in the garage, including the garage door opener. Assuming you open the garage door (say with a remote garage door opener) while the car is charging, it will trip the breaker in the basement. IIRC your average garage door opening motor uses 500W to 700W while in operation.
So at the least I need to install a second circuit. But the cost of installation is mostly tied into labor rather then material since it involves bringing out a trenching machine out. And the cost difference between just 1 extra 120V circuit and a full blown 240V service with subpanel is significant, but not bad enough for me to think it's makes sense to penny pinch there.
Edit: Well in theory you could also have a receiver and relay that cuts off the charging to the car before initiating powering the garage door motor. That said I don't think it's worth the hassle... at minimum that's two electrical mechanical relays for the 120V lines, some sort of RF receiver for the car, a controller for the relays and to probably some way to signal the garage door itself (replacement for the button inside maybe), and way for the controller to state of the door itself so that it doesn't cut power at the wrong time. Certainly hackable but I doubt I could build it reliable without way more money and time spent on it.
Will it? It’d depend on the breaker and load rating of the wire run to the garage.
I can draw 6kw from one 240v, breaker, so about 25 amps, for a few minutes before it trips from thermal overload.
I load tested a new outlet that was wired on the same circuit, with five devices plugged in, kettle, pressure cooker, slow cooker, fan heater, and hair drier for good measure.
The breaker should trip before the wire is damaged, it did.
So at the least I need to install a second circuit. But the cost of installation is mostly tied into labor rather then material since it involves bringing out a trenching machine out. And the cost difference between just 1 extra 120V circuit and a full blown 240V service with subpanel is significant, but not bad enough for me to think it's makes sense to penny pinch there.
Edit: Well in theory you could also have a receiver and relay that cuts off the charging to the car before initiating powering the garage door motor. That said I don't think it's worth the hassle... at minimum that's two electrical mechanical relays for the 120V lines, some sort of RF receiver for the car, a controller for the relays and to probably some way to signal the garage door itself (replacement for the button inside maybe), and way for the controller to state of the door itself so that it doesn't cut power at the wrong time. Certainly hackable but I doubt I could build it reliable without way more money and time spent on it.