Two Teslas in the Garage but One Charger....

Two Teslas in the Garage but One Charger....

My Model S is a year old and have a Model X reserved for 2015...
Don't think that the Wall Charger cable will reach both so we will have to move the cars around to charge them.
Hmmm...could Tesla offer a "right hand" (IE, on the passenger's side) charger port on the Model X so it will be close enough to reach? Or a longer cable?


NumberOne | 2014年6月25日

Unfortunately everyone else who have already had their HPWCs installed planned on everything being standard, so I doubt it is going to change.

The driver side rear is simply the most logical location. My intention is just to park the cars close to the HPWC on alternate days. Of course a slightly longer cable is a possibility, especially since Tesla does sell replacement cables already.

cathygardner10 | 2014年6月25日

Geez...I am counting on using the charger from my husband's "S" for my X ... I better get out and measure. We mounted it on the wall just inside the garage door, anticipating that it would eventually take care of two cars - I think it can cover the distance....

petero | 2014年6月26日

Jhbeak. How are you charging your MS now (Wall Charger or Mobile Connector)?
If you are using the MC ask your electrician if you can add a second outlet. You could plug your two MCs into each 220-240 outlet and set the timers in each car so one car charges at a time.

The MC cords should be long enough. Just a thought.

jdb | 2014年6月26日

I'm planning to just rotate vehicles. With HPWC in garage can easily charge one vehicle when get home from work and then before going to bed for night spending a few minutes rotating cars and putting charger into other vehicle.

bevguy | 2014年6月26日

NEMA 14-50 extension cords are available and work fine. Make sure the wires are the right gauge. On line calculators are available to size them so that there is less than 1 volt current drop. I know Tesla doesn't recommend them but they are used in the Service Centers.

Brian H | 2014年6月26日

Take turns, every second day. Unless you use more than half a 90% charge per day.

Laryrob | 2014年6月27日

agree re every second day.Luckily my cord will reach both when in the garage. May do a second 240 outlet though

jjs | 2014年6月27日

For those with an existing 240 outlet wanting a second 240 outlet in the garage and
a) don't have enough amps coming into the house, or
b) don't want to pay for running it all the way from the circuit box
you could have a second outlet put in the garage on the same circuit. Then dial down the amps for charging at this location to 1/2 of 80% of the rated circuit.

Example: You have a 40 amp 240 circuit running to your garage. (40 and 50 amp 204 circuits are the most common size). You should never run more than 80% of that for an extended period of time so that takes us down to 32 amps. For one car this would be about 24 miles and hour. If you dial it down to 16 amps you can both be plugged in anytime you want, no need to swap places or trade turns. Each would charge at about 12 miles per hour each night.

If one of you drive more than the other the ratio does not have to 50/50. 20 amps and 12 amps, 25 amps and 7 amps, etc would all work fine as well.

The above configuration is not right for everyone, but in some, perhaps many cases, this would be a good solution.

Brian H | 2014年6月27日


jdb | 2014年7月1日

Good point Brian H. Every other day refueling at HPWC would work, rarely drive Model S more than 125 miles in day. And on those occassions when drive both vehicles a lot with the HPWC could rotate later in evening. Not a big deal.

Ohmman | 2014年7月2日

jjs - only downside to your setup is the loss of efficiency since it has been shown that the lower the amperage, the lower the charging efficiency. Counterintuitive at first glance, but true. Convenience is likely worth the lost efficiency. Swapping each day would be hard to remember, at least for a guy like me.

jjs | 2014年7月2日

Ohmman - Indeed there is a cost in lost efficiency. Does anyone out there have any specifics on how much is lost? 10% 20% more?

Sin_Gas | 2014年7月4日

I can't believe it. You can pop for almost 200 grand for 2 cars, and you want to cheap out for a couple of grand for an additional charger? Does this make any sense to anyone?

Sin Gas

jjs | 2014年7月5日

Yes there are a number of variants where this makes sense. If you live in an older home your house is most not likely wired with enough amps to the house. The expense, mess and time to do this may not be as desirable as less invasive measures.

You may have solar panels and don't want any/additional amps run to your house from the grid.

You may rent and have little or no control of additional outlets/wiring.

As I said above there are a number of reasons.

Sorry to be rather blunt, but this makes more sense than assuming all are in your situation and asking "Does this make any sense..."

grega | 2014年7月13日

I wonder if a software upgrade could have 2 cars balance their charge load on a 240v setup.

the bonnie | 2014年7月13日

Just set the timers for starting the charge on each car to ensure that one starts after the other will have finished.

jdb | 2014年7月13日

To follow up with @Sin_Gas and @jjs, many reasons not to want or need two chargers in garage other than price, which is not issue. In my case the two car garage is now one car garage since a large part has been taken over by riding lawn mower and power tools and extra refrigerator and kids bicycles and wife's gardening supplies, I would get in big trouble to evict those for purpose of installing another charger to park second vehicle which in any case would not be necessary. The HPWC is more than sufficient for every other day charging or if needed, simply rotating vehicles in evening.

grega | 2014年7月13日

you'll never have 2 teslas in your garage though right, which was the thread question

jdb | 2014年7月14日

Correct unless I built a backyard utility shed for all the other stuff which is possible, but even then would not plan to put in additional charger, think one HPWC is sufficient.

TrexTesla | 2020年3月22日

I see this thread was dated, thought I'd ask the question again to see if anything has changed, or is the swap the cars every other day the best/cheapest option if you can't install another charger. I plan on getting a Y for my wife and I have a 3. She only drives about 20 miles in a day, and I'm varied between 40-150 per day. So, I can easily do her car every third day, but I know the recent recommendation is to plug in every day. Any thoughts on a better way?

ratchet | 2020年3月22日

@TrexTesla - If you have a NEMA 14-50 outlet, you can purchase a 30' extension (mine was about $110) to extend the reach of your mobile charging cable so you don't have to juggle cars. If you have the HPWC, you need to swap vehicles, assuming there is a physical layout issue. One theory of the recommendation for charging every day seems to be that Tesla doesn't want to be blamed if someone forgets to charge and then runs out while on the road. If you get in the habit of charging every day, you probably won't forget. If you plan your charging so that you plug in when you have no less than 20% charge, you will be fine. In fact, you might find that charging less frequently could be better for the battery.