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Charging dilemma

Discussion in 'Model S: Battery & Charging' started by gr2020, Apr 22, 2017.

  1. gr2020

    gr2020 Member

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    I just ordered my first Tesla (75D), which should be here in June. I'm trying to get my charging situation squared away, and I'd love some input.

    I work at home, so I don't have a regular commute to worry about.

    My house has a 125A main breaker, and my electrician determined I have 26A of capacity available. Further, there are no empty slots in my panel for additional breakers (ugh). So, my options come down to the following:

    Option 1 - install a 30A circuit to the garage; this will require addition of a new sub-panel, as there are no open slots for new breakers on the existing panel. Total cost for this option will be roughly $1200, including a 14-30 adapter. A downside here is I've spent $1200, and I'd still need to pay almost all of the cost of option 2 to upgrade service any higher - all of the costs for the option 1 subpanel are throwaway in that case. Charge rate would be 26A, around 17 mph.

    Option 2 - upgrade service to house to 200A, and install 50A service to the garage. This requires a new panel, along with all of the new requirements to meet code (new meter housing, etc.). This would come to about $2750, and would provide 40A charging.

    Option 2a - I think if I go with option 2, I'd probably add a HPWC for an incremental $500, just for the convenience. I'd presumably wire it in at 60A, so I could charge at 48A.

    Option 3 - I'm not really considering this - but if I replaced my electric range with gas, that would free up enough capacity to run 50A to the garage with no further upgrades. Cost here about $800 plus buying a new range, plus buying other new kitchen appliances to match the shiny new range, plus new granite countertops...ha. Clearly an expensive way to go. :)

    Any thoughts?
     
  2. Barry

    Barry Member

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    Surprising your panel is only 125A for a not that old house (based on your location) with electric appliances. You can charge at 24A with a 14-30 which will give you about 15mi/h. Working from home, that may be fast enough for your needs. Only you can determine that. For example, if you make a trip to Summit Co., and don't charge in Silverthorne, it will take about 12 hours of home charging to bring you back up to 90%.

    OTOH, if you are even thinking about any other house improvements in the future, then go for the 200A service, as you'll need it anyway.
     
  3. danbucks

    danbucks Member

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    I don't know if you are considering other options, but: it boils down to what matters to you most.
    Cost? Cool factor? Long term flexibility?

    That said: "I work at home, so I don't have a regular commute to worry about."
    Seriously, having driven a Nissan Leaf and a X... with that sort of schedule, you have all night to charge, in almost every circumstance. I've charged the LEAF (not the X) @ 120v many times ... you are fine with Option 1.
    You will discover times where something happens (holy S!#$%, I forgot to plug in) ... but, it is extremely rare. This is a viable option.

    Option 2: no one on this forum can answer this without a load analysis of your house.
    What I will say: I did 14-50 to the garage, and a HPWC maxed at 40 amps.
    While the 40 amps for me is completely irrelevant (e.g. 27 amps would be fine... except one time where it was: "holy S!#$%, I forgot to plug in") ... I love the massive-can't-be-destroyed-gauge-cable of the HPWC. Others may hate it because it is HEAVY.

    If you are close at maxing out your current Main already ... consider 200A for safety. Otherwise ... your choice.
    If you choose 200A, I love the HPWC cuz it's just there... all the time... cables will not tangle because they are massive compared to the mobile one ... and the mobile stays in the X. Always. Amperage setting on the HPWC for you.... irrelevant.
     
  4. gr2020

    gr2020 Member

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    Ya - I was surprised too!

    I like this - it's always there, I don't ever have to worry about not having the mobile cable in the car if I happen to need it (if I left it in the garage), and I can place it in a different location in the garage (at the nose of the car, instead of the side) since it has a 24' cable instead of 20', which I like. Although I guess the HPWC decision is really separate from the 30/50/60A one, as I could use it with either.

    I think most of the time, the 30A it would be fine. I'm just worried about those occasions when I need to come home after say 100 mi, then pop out a few hours later for another 100, and maybe it's on a cold day/night so I have less range... Although I'll be the first to admit I'm making up scenarios here that do happen, but not often.

    Thinking about it, I think a better way to look at this is, the $1200 is essentially a sunk cost (it's the minimum I can do to charge at more than 110V). And for an incremental $1500, I can get upgraded service. And $500 on top of either for the HPWC.
     
  5. cziegler

    cziegler Member

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    I suspect eventually most everyone will have an EV, therefore, I build-out all my properties with at least a 200 A panel to support 1 HPWC (or a similar J1772 charger) and a couple of NEMA 14-50 to accommodate visiting guests and additional EV equipped residents. As a side note, we have 4 EV's and we've never really needed more juice than the 40 A that we pull through the NEMA 14-50

    Another timely consideration may be the installation of solar PV or a Powerwall.
     
  6. BrettS

    BrettS Member

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    One comment I have here, having just purchased my Model S about 3 weeks ago and having installed an HPWC next to the charge port on the side of the car is that you really do want to install it as close to the side of the car as you can. My HPWC has a 24' cord so that I can stretch it out to the driveway to charge there if I need to, but most of the time it's just looped three times over the charger. When I plug in or unplug the car all I need to do is reach over and grab the handle and plug it in, or disconnect it from the car and stick the end into the hole in the charger.

    Since you will likely need to do this frequently (probably every time you drive the car) I feel like uncoiling the cable from a charger at the nose of the car and running it next to the car, and then recoiling the cable when you disconnect the car would get old very quickly. I know some people have run the cable up along the garage ceiling and let it dangle down near the charge port, so that's an option too, but you will definitely want to figure out some way to keep the car end of the cable as close to the charge port of the car as possible.
     
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  7. brucet999

    brucet999 Active Member

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    Is your clothes dryer gas or electric? If it is gas, or if you could change to gas, you would spend less money drying clothes and free up space in the panel by replacing the 30A dryer breaker with a 50A breaker (thus eliminating need for a sub panel) for a 14-50 outlet or HPWC in the garage. You might even be able to fudge the limits a little to install a 60A breaker for the HPWC. Remember, you will never charge the car during peak usage times when rates are highest, so fudging nameplate capacity by 4A would not be a problem.

    Regarding option 2, do you know that incoming mains from the poco are capable of supporting 200A? In my neighborhood they are not, so upgrading to a bigger panel would cost thousands for higher capacity underground lines from SCE's distribution vault.
     
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  8. gr2020

    gr2020 Member

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    Hmm - that's an interesting point. I usually park on the right side of the garage for convenience getting in and out, and there is a motorcycle on the other side. I was thinking the placement options were:

    a) right side wall, near the garage door. Advantage is it's close, but disadvantage is it's on the right side of the car, and when the garage door is closed there isn't enough room to easily walk behind the car without potentially rubbing up against the car or the door, and getting dirty. If I just do a 14-50 or 14-30, this is probably where it will need to go, since the cord is only 20'.

    b) front wall, near the nose of the car (next to the interior door). 20' cable wouldn't work well here, but 24' would reach without a problem. My thought here was I could just leave it stretched out on the garage floor to the charging port most of the time, as there aren't any other cars that might drive over it; it would also easily reach if for some reason I wanted to back in on the other side of the garage.

    Parking on the left side of the garage is an option (and the charger could be on the left wall), but less convenient to enter the house since I would have to walk around the front or back of the car, where there isn't a lot of room.

    I'm totally open to suggestions here!
     
  9. gr2020

    gr2020 Member

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    The dryer is electric - that's certainly an option. Not sure what it would cost to get gas to there, but it's within 10 feet of a gas fireplace, so presumably the gas is somewhere close!

    Well now there's a good question...I just emailed my electrician to ask him about it. My neighborhood was built out in 1994, which doesn't seem like too long ago, so I assumed it wouldn't be a problem, but you know what they say about assuming!
     
  10. gregd

    gregd Active Member

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    For what it's worth, I charged my Roadster for several years at 24 amps, using the dryer plug. Never had a problem with not enough time to charge.

    You might look for a "Dryer Buddy" to share the dryer plug with the car, perhaps in the short-term to get a feel for what sort of charging current you really need.

    Regarding the panel upgrade, I did one last December (also went from 125 to 200 amps) and we had the power company come out and investigate what my options were. Got lucky and we were ok. But they also said that if they had needed to upgrade, it would be on their nickel, but a mess for time, trenching the yard, etc.

    One last comment, presumably your electrician checked what kind of panel you currently have. 1994 is probably new enough (mine was early 80's), but some places they were installing a type of panel that later on tended to fail (as in, catch fire). They're known as "Zinsco" panels around here, perhaps by other brand names elsewhere. If you have one, I'd replace it just for that reason alone. I had the same full-panel situation as you, and that made the decision easy, if not expensive.
     
  11. brucet999

    brucet999 Active Member

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    +1
    Also FPE, (Federal Pacific Electric) were even worse, with as much as 30% out-of-box failures - breakers that would not trip under as much as 150% of rated load..
     
  12. JSkrehot

    JSkrehot Member

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    Exactly what I was going to ask, as I am doing this exact thing for my upcoming Model 3. We have a gas dryer and do not use our 30A breaker that is wired for a dryer.
     
  13. Hugh Mannity

    Hugh Mannity Mediocre Member

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    My place is only 100 amp service and my electrician gave me a 240V 24A service for the car. Have electric stove, dryer and some baseboard heating. Am careful though, the car only charges at night when the stove and dryer aren't running.
     
  14. BerTX

    BerTX Active Member

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    Just a question about the sub-panel -- if your main box can't hold any more breakers, then how are you going to install it? It requires a breaker in the main panel.

    I'd upgrade the service. Your going to spend $700 for windshield wipers and keyfob batteries in the first year, so if you can justify that to own a Tesla, then a wiring upgrade is easy.
     
  15. gr2020

    gr2020 Member

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    That's why option 1 (for the 30A circuit) was $1200 - it includes a small subpanel, and some breakers would move to that.
     
  16. deonb

    deonb Supporting Member

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    Probably stating the obvious here, but I assume you've looked at just using 2 twin breakers across 4 of your existing 120v circuits, thereby opening up a space for a 240v breaker?
     
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  17. gr2020

    gr2020 Member

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    Thanks for the tip - I'm not sure if my board will accept them, but I will look into it!
     
  18. Bet TSLA

    Bet TSLA Member

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    Yeah. Getting a first EV is a lot like having a baby -- everybody will tell you about all the crap you just have to have, but the fact is that you need none of it. What I did when I got my Tesla was... absolutely nothing. Things stayed that way for a few weeks while I observed what was unacceptable about the situation. I quickly determined that an HPWC would be overkill, but that something was needed. So I got a NEMA 14-50 and it is proven to be just fine for my needs. Yes, I can imagine situations where it wouldn't work, but they have never happened.

    Given your location, I bet you'll find that when you have to travel real distances there will always be a supercharger available to make sure you don't arrive home completely empty. And the days that you have to travel over 200 miles locally will be rare to nonexistent. In an emergency you can always call Lyft or Uber.

    So I suspect that sharing your dryer outlet would work for you. Give it a few weeks to find out. The right thing to do, of course, is to upgrade to a 200 amp or greater service and set everything up exactly how you want it to be. How else will you be able to accommodate your additional Model 3 when you get it? But you won't really know what you want until you spend some time with your new car.
     
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  19. Btrflyl8e

    Btrflyl8e Supporting Member

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    Luckily, I had to replace my glass fuses with a real panel (hello, 1959) in 2003 when I had my pool put in. Since we had to do the whole thing anyway, I paid to have the service upgraded to 200 amp. Good thing, because I had room for one 50amp when the Tesla came in 2013. I've been using a 14-50 ever since. It's plenty fast, I've never had a situation where I wished I'd had an HPWC.

    I say, bite the bullet for future-proofing and upgrade now to 200A. I wouldn't bother with the HPWC, but that's just me. I think it's overkill, at least it would be for me.
     
  20. HankLloydRight

    HankLloydRight Fluxing

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    Lots of good suggestions here, but my 2c is that if you work from home (as do I), you typically have all night and most of the daytime to charge. Therefore, I'd go for the simple 30a $1200 solution (especially if you can double up 4 breakers and add one 240v breaker so you don't need a subpanel).

    You just have to remember to plug in every few days (or everyday if you want), and especially if you are planning a long trip.
     

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