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one charging station for 2 EVs

Discussion in 'Model S: Battery & Charging' started by gtsai, Feb 23, 2017.

  1. gtsai

    gtsai New Member

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    Hi. I am looking for a single charging station with 2+ standard J1772 connectors. Any knowledge of a house version one? not looking into the openEVSE project as i've burnt $$ and time and all the above into that. not into the $8k commercial ones either. I have a chevrolet Volt and a Model S, but this topic if for all future expanding families trying to avoid gadget collection at home. Thanks.
     
  2. sdorn

    sdorn Director of Awesome

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  3. Jason S

    Jason S Model S Sig Perf (P85)

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    The mobile adapter plus a 50Amp circuit would likely work well.
    *edit*... sorry, didn't realize you wanted to charge at the same time. Two 14-50 sockets? $3500 seems awful expensive just so you can charge simultaneously.
     
  4. sdorn

    sdorn Director of Awesome

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  5. Blup85

    Blup85 Member

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    seems like it would be much cheaper to buy two separate chargers @ $600 a piece. You will run multiple #6 circuits anyway, or if a 6.6kw lvl 2 is all you need #8's. wiring will cost the same. either way (double unit or two singles)
     
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  6. brkaus

    brkaus Active Member

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    #6 brkaus, Feb 24, 2017
    Last edited: Feb 24, 2017
    You could always go the route of a converted HPWC for the second car. It would still allow load balancing so the circuit would be shared. Technically, not a single station, but would also allow future upgrade to 4.

    80A home charger, HPWC, High Power Wall Charger, Tesla

    It is a premium price for the conversion, but it would give you two chargers for ~$1500 and it should just work. I'm starting to look at used Leaf for kids car... this is the route I was considering.
     
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  7. Blup85

    Blup85 Member

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    Well, you live in Nevada, so I'm guessing you are going to need to take advantage of time of day rate schedules (I'm jealous, .05c/KW for off-peak, here in Norcal my off-peak is 12c!). So a charger like Chargepoint's home charger that has scheduling (for the non-smart Tesla) is a must. If you can get by with 20mile/hour charge rate for both the tesla and j1772 then buy two chargepoints for $500ea. If not, just buy the right tool for the job, 1 HPWC and a 500 single charger. You can always sell the HPWC if the mission changed (they will always have a good value to be re-sold)

    Home EV Charging Station for Electric Car - ChargePoint

    And if your truly planning for the future, just make sure you oversize the wire for the j1772 to accommodate another HPWC for the future Tesla...
     
  8. gtsai

    gtsai New Member

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    Thank you all for your input. This will be important for all houses in the future if you consider that the average house connection to the energy company is 200A. In my area, Las Vegas, two ACs 40Ax2 plus 3 cars @40A would be this 200A, which is what i am trying to avoid here with one single charger limiting either the maximum output or the amount to one car another. And i also have solar panels, which on theory alleviates that single street cable, but it also strains my home infrastructure. On this criteria, only the HPWC 80A is reasonable, but its cost...
    as pointed above, 3 chargers are cheaper than a single with 3 outputs- makes no sense, there's a business waiting!
    On my google research, i found a thread at gm-volt- Question About Charging Two Volts in the same Garage
    and for the DIYs-https://code.google.com/archive/p/open-evse/wikis/Hydra_EVSE.wiki
    there was a thread in a prius forum, can't find it anymore.
    Hope this helps in our planning for future.
     
  9. brkaus

    brkaus Active Member

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    I would argue there is very little cost savings from a single enclosure. The expensive parts are power handling and the cord.

    Also, most houses wouldn't benefit from a single 2-3 headed charger. Cord logistics wouldn't work out the best.

    It wouldn't be bad if someone offered a inexpensive j1772 charger with the features of the HPWC - possibly even a 40a one.
     
  10. GSP

    GSP Member

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    @gtsai,

    For homes without lots of extra capacity in their panel, the 2-4 HPWCs sharing a single 50 A circuit is the best setup that I am aware of. The new HPWCs are pretty smart about sharing power between cars so that they all get charged up.

    For non-Tesla cars, you need to purchase a J1772 cable to replace Tesla's proprietary connector. The J1772 cables get quite a bit more expensive for higher ampacity, but if you are going to limit the HPWC to 40 A (max for 50 A circuit) then only buy a 40 A cable.

    GSP
     
  11. miimura

    miimura Active Member

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    Clipper Creek recently came out with a version of their EVSE that will do it. Let me find a link.
    Here it is. Share2 - Two HCS-40 stations that can be installed on one 40 amp 240V circuit.
    32A Level 2 EVSE Share2™ HCS-40 Bundle| ClipperCreek

    It works basically the same way as the new HPWC where they communicate with each other so that the combined draw stays within the single circuit rating. This is slightly cheaper than the total cost of one standard HPWC and one converted to J1772 by Quick Charge Power.
     
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  12. TonyWilliams

    TonyWilliams Active Member

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  13. TonyWilliams

    TonyWilliams Active Member

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    You could save a little money and use a 40 amp setting on the HPWC plus "slave" a second lower cost 40 amp J1772 conversion for less money.
     
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  14. brkaus

    brkaus Active Member

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    Wow, I looked just looked around based on your comment and the cables are much more expensive that I would have imagined. Interesting data point!
     
  15. davewill

    davewill Member

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    #15 davewill, Feb 27, 2017
    Last edited: Feb 27, 2017
    Without going the DIY/OpenEVSE route, this is the cheapest way I know of to share a single circuit, which is what it sounds like you really want. Since most of the cost of an EVSE is in the cable, putting two cables on one EVSE isn't all that helpful price-wise.
     

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