TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

Charging conundrum for multiple EVs

Discussion in 'Model 3' started by McHoffa, Jul 8, 2016.

  1. McHoffa

    McHoffa Member

    Joined:
    Sep 29, 2015
    Messages:
    589
    Location:
    Canton, NC
    I know there are lots of discussions as to which charger is better to install, and why, but I'm hoping someone here has a similar situation that they've already figured out.

    Background: I have a 200 amp service with plenty of space. I run a heat pump, with electric backup heat for < 20º nights. I have electric dryer and stove as well.

    I am planning on selling my current car later this year and buying a used Nissan Leaf (this will get passed to my son) and I have two Model 3s preordered.

    So what I am trying to decide is if it would make more sense and if it's possible to install two 14-50 outlets, or a HPWC and a 14-50, or if there is actually an adapter I can use to charge the Leaf on the HPWC and then I could just buy one of those.

    Anyone else have multiple EVs or plan on having multiple once they get their Model 3(s)? If so, how do you charge and how do you juggle them on one or two chargers?
     
  2. ChadS

    ChadS Petroleum is for sissies

    Joined:
    Jul 16, 2009
    Messages:
    2,401
    Nightly juggling is a real pain. Best to have a dedicated charge point per car if there is any way to swing that. They don't have to be fast - especially not ALL of them. An occasional juggle to get a faster charge is not a big deal.

    It doesn't have to be much. At our old house we had two 14-50 outlets with mobile connectors plugged in to them (only removed for road trips), and the 3rd car used a 120V outlet (fine as long as you average less than 40 miles per day on one of the cars; about half of all LEAF owners do this, and quite a few Tesla owners. Not recommended long-term for Roadsters though; the capacity estimate gets off if you use 120V regularly).

    Our new house is similar except we did install an HPWC instead of one of the 14-50 outlets. It was just kind of because the new house had the capacity and it was nice to get the HPWC built in just in case, but we really haven't needed it.
     
  3. cpa

    cpa Member

    Joined:
    May 17, 2014
    Messages:
    940
    Location:
    Central Valley
    McHoffa,

    I do not know your daily driving situation for you and, presumably your spouse. So, I will share what my wife and I agreed to do when we receive the Model 3 for her:

    We have a three-car garage, with individual doors for each spot. We have 200A service too. We installed a 14-50 between the first and second doors. Our Model S parks in the second slot. We have a rack bolted overhead that we use to wind the UMC around.

    I work from home, and my wife is retired. She generally drives <100 miles per week running errands and so forth. I drive about the same except during tax season when I have clients all over, and I work out of town 6-7 days per month.

    We figured out that we can keep the Model S on the 14-50, and install a 20A 110V plug on the garage wall next to where she will park the Model 3. Her car will almost always be parked in the garage from 7PM to morning, so 12 hours of charging easily will add 60 + miles of range by 8AM. If there is the rare occasion that she needs a faster charge, we can just use the UMC from the Model S to plug into her car.

    Just throwing this out there . . . (Nice problem to have!) :)
     
    • Like x 1
  4. idoco

    idoco Member

    Joined:
    May 7, 2013
    Messages:
    162
    Location:
    Outside Philly
    Could daisy chain HPWC off one circuit and let them control current to each vehicle.

    What's up with HPWC?
     
  5. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,761
    Location:
    Texas
    I have two circuits and a 200 amp main panel: a 50 amp for the 14-50 that hooks up to the Tesla, and a 40 amp for the 32 amp Clipper Creek that charges the Leaf. In case of problems, the Leaf can charge off of 110 and the Tesla can charge off the Clipper Creek. Both are happy to charge at the same time.
     
  6. aesculus

    aesculus Still Trying to Figure this All Out

    Joined:
    May 31, 2015
    Messages:
    1,969
    Location:
    Northern California
    Not when one is a Nissan Leaf. But it would work for the 2 Model 3's he has planned.
     
  7. McHoffa

    McHoffa Member

    Joined:
    Sep 29, 2015
    Messages:
    589
    Location:
    Canton, NC
    I work from home, my wife drives about 50-60 miles to and from work on a normal day, obviously sometimes more. My son will most likely never need to drive more than 20-30 miles in a day until after early college in 4 or 5 years (which is why an older Leaf is perfect for his first car).

    I can easily charge during the day while my wife would plug in at night, and the Leaf would need to be nightly, but slower rate is fine.

    I guess one NEMA and one Clipper Creek would be perfect for me too. If only I had a garage. These, for now, will both be uncovered. Trying to decide on a carport size (after I get my driveway redone with either new asphalt or concrete, another big decision to make)
     
  8. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,761
    Location:
    Texas
    Just have a weatherproof box built around them with only the cable showing.
     
  9. Evbwcaer

    Evbwcaer Member

    Joined:
    Jun 21, 2014
    Messages:
    470
    Location:
    Minnesota
    Quickchargepower.com will put a j1772 head on an HPWC.
     
  10. GarrickS

    GarrickS Member

    Joined:
    Apr 5, 2016
    Messages:
    66
    Location:
    Inglewood, CA
    I have a Model S and a Fiat 500e using 2 14r-50's on the same circuit. The Fiat is scheduled to charge from 4am to 8am (4 hours is enough for a complete battery charge). The Model S is scheduled* to charge from 8am to 4am (all other hours).

    *I've only had the car a few days and haven't actually done this yet; but that's my plan.
     
  11. Evbwcaer

    Evbwcaer Member

    Joined:
    Jun 21, 2014
    Messages:
    470
    Location:
    Minnesota
    How are you going to schedule the cars? The S only has a start time option.
     
  12. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,761
    Location:
    Texas
    There should be no reason to do any complex scheduling. Our Leaf and Tesla charge at the same time (more or less depending upon how much driving is done during the day).

    Assumes two circuits.
     
  13. Evbwcaer

    Evbwcaer Member

    Joined:
    Jun 21, 2014
    Messages:
    470
    Location:
    Minnesota
    GarrickS says they are on one circuit. So as I understand it he limited to 40 amps at any given time.

    I guess you could dial the tesla down to 25/30 amps and give the other car whatever it need from the remaining amperage.
     
  14. McHoffa

    McHoffa Member

    Joined:
    Sep 29, 2015
    Messages:
    589
    Location:
    Canton, NC
    I would probably just plug mine in first thing in the morning. She or I would plug hers in when she got home from work.

    The Leaf would get plugged in after school/work or whatever and unplugged when I get up and plug mine in.
     
  15. GarrickS

    GarrickS Member

    Joined:
    Apr 5, 2016
    Messages:
    66
    Location:
    Inglewood, CA
    Hah! So I just discovered this when I tried to do it. I've only had the car a few days and had just assumed feature parity with the Fiat.

    I'm not sure what to do at this point. I don't want to risk both cars charging at once, popping the breaker, and waking up to uncharged cars.

    I either need to use 2 Juiceboxes that can talk to each other, or 2 HPWCs that can talk to each other with 1 converted to a tesla handle. Meh.
     
  16. cronosx

    cronosx Member

    Joined:
    Jun 1, 2016
    Messages:
    188
    Location:
    Italy
    Search on the S forum, there is some tool online that using the API of the car can start/stop the charging at a specific hour
     
  17. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,761
    Location:
    Texas
    To even come close to following code there needs to be a switch so that only one outlet can get power at any one time.
     
  18. David_Cary

    David_Cary Member

    Joined:
    Dec 17, 2012
    Messages:
    607
    Location:
    Cary, NC
    No there isn't - at least not in the US.

    Leaf and S here. Juggled for a while which was really tough with our TOU. Finally got a 14-50 installed.

    I will tell you I have 400A service - large mostly electric house. That is standard without EVs around here with large houses. I have 2 interior panels (basement) that are each protected by a 75 or 80A breaker. When I go to 40A on the Tesla and charge the Leaf (at 20A), I have flipped the breaker. It has other things on it and of course needs to be derated by 20% for constant draw.

    One of the panels was easier to get at without drywall work and I put the 2 circuits on that one. Stupid in retrospect. I mostly leave the Tesla at 30A.

    Just remember in your planning to consider TOU. In CA, they have some super off peak that is only 4 hours long. We may all get this someday. Also consider peak demand charges (I have these). If I charge my car at 40A for 15 min in a peak time period, my surcharge for that month goes up $30. I typically peak at 4 kw and they are $5 a piece. So I typically pay $20, but if car was charged full speed, it would go to $50+. So a one time 15 min charge to get 7 miles, could cost $30 (and up to $50). If my wife had a 120V with the Leaf and just plugged in all the time, my peak would certainly be 1.2 kw higher every month. It adds up.

    So wire maximally for max charge rates for all cars if it isn't much trouble and you are staying put for the long term.
     
  19. McHoffa

    McHoffa Member

    Joined:
    Sep 29, 2015
    Messages:
    589
    Location:
    Canton, NC
    I hope 200 amps is enough for my needs. I actually just had it upgraded from 100 amps earlier this year to install the heat pump. I asked the electrician about charging the Tesla, either via 14-50 or the HPWC and he said 200 would be plenty. That was before I decided to preorder the second Model 3 on reveal night, and before I decided to trade my Fit for a Leaf. Should have just paid the extra anyway and got 400 amps.
     
  20. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,761
    Location:
    Texas
    Shouldn't be a problem. Our larger loads are A/C (It's Texas so this is significant most of the year), S85, Leaf, 6 KVA UPS. No problem with 200 amps.
     

Share This Page