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Two Evs

Discussion in 'Roadster' started by vfx, Apr 9, 2007.

  1. vfx

    vfx Well-Known Member

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    Ms.CEO brings up a good point. My wife and I had made a similar agreement and it makes one think about the prospect of two Evs charging in the garage at night. Would that not require an unusually large power draw? I believe the Roadster can be "programmed" to when it starts to draw. Maybe the two cars can be offset in charging time.

    e
     
  2. CEOswife

    CEOswife Member

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    The engineers at Tesla are well aware of this issue. Currently dual-Tesla owners will be required to program each car to begin charging at different times. They have been thinking of an automatic system where multiple Teslas can negotate for charging resources, but nobody is yet actually working on it. Right now, they are currently focused on shipping the Roadster, so standby for a better solution for this dual charging problem.
     
  3. malcolm

    malcolm Active Member

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    [​IMG]

    The old XJ6 had two filler caps, one on each side of the vehicle as you can see.  What if Whitestar has the same feature?  Two identical 70 Amp sockets mounted on either side of the vehicle.  Now the Mobile Charge System obviously has a cable that fits the Roadster and hopefully will fit Whitestar as well.  Here's the idea.

    Redesign the Mobile Charge System so that the cable which plugs into the Roadster is rated for 70 Amps AND can be removed from the Mobile Charger becoming a single 70 Amp cable with a Tesla-compatible plug at either end.

    You park the Whitestar in the garage next to the 70 Amp Home Charging Unit and you park the Roadster next to the Whitestar furthest away from the charger.  Plug the cable from the Home Charger into the Whitestar and use the spare charging socket on the other side of the Whitestar to run the 70 Amp cable borrowed from one of your Mobile Chargers into the Roadster.

    You effectively daisy-chain the cars together.  Obviously power losses may be an issue,

    Whitestar acts as the intelligent negotiator between the Roadster and the Home Charger.  Assuming both cars will have the same size of storage and both are empty, it will take a maximum of 7 hours to fully charge both (2x 3.5 hrs)

    Obvious issues - added weight and electronics to Whitestar.
    Daisy-chaining only possible if your garage is big enough.
    Cable between Whitestar and Roadster must be long enough so you can park, get out of the car without bashing paintwork and still connect them together.

    Rather like V2G, this also raises the possibilty of V2V:-

    Mr Eberhard: "Hi honey, er... forgot to charge the Roadster, can you drive over and give me a charge?"
    Mrs Eberhard "Again? I swear you only bought me this thing as a mobile fast charger for your own car! Ok, be with you in half an hour"
     
  4. tonybelding

    tonybelding Active Member

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    Incidentally, my Esprit also has gas caps on both side of the vehicle. (It actually has two gas tanks connected internally with a hose, which makes it a bit balky about getting both of them full.) I raised this subject a while back with Tesla. . . Although I was thinking only of the convenience factor, I never thought about "daisy chaining" the cars. The answer was that two charging sockets would increase costs, and also they chose a port on the driver's side as a reminder to plug your car in.

    Still a neat idea. . . Maybe something will come of it in future designs.
     
  5. malcolm

    malcolm Active Member

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    Maybe. Daisy chaining does mean additional weight/complexity/cost to all subsequent Teslas if the idea catches on. I think the size of most peoples' garages and the limits on overnight domestic charging would mean you can't daisy-chain more than two cars together - but I don't know. TH!NK have small cars. So do Smart. You could fit up to four Smart-sized EVs in one double bay garage. Daisy-chaining those would be fun. :eek:

    The V2V feature, if implemented, could be restricted to just Tesla cars only, or to all cars which use Tesla Energy Group battery systems, or - if you don't mind charging at lower currents with a Mobile Charge cable with lots of different plugs - any Tesla Energy Group car could be used to recharge any other make of EV.

    It's the same idea as ICE drivers carrying jump leads or a can of gas and being willing to help stranded motorists.
     

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