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Model X man maths v Tesla

Discussion in 'The UK and Ireland' started by Dan43, Jul 19, 2016.

  1. Dan43

    Dan43 Member

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    Running the numbers it is certainly that all the man maths hasn't helped, can't see there is much in it overall, if going non-ICE then it is just the petrol/diesel savings per mile = to the cost of your electricity per KwH at home/work, those being the two main points of charging the battery for most users. Hmmmm...... £64K is a lot of change to save about £1000 per year on fuel.

    So a rough summary is Tesla is a choice made for reasons not so much to do with any tangible overall savings but due to other reasons of the heart/mind conundrum. In essence if you like it just go buy one :) If not don't.

    Do most here entertain the eco reasons in this equation or does it boil down to a test drive and it was just a car I liked and wanted to buy, nothing to do with anything Tesla is adding to the overall purchase pot (eco, sustainability, savings vs fuel etc)
     
  2. EV-lutioin

    EV-lutioin Member

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    My Model X is powered by solar, that makes me very, very happy. :) That my solar powered car came in the package of a Tesla with all it's awesomeness just sweetens the deal.
     
  3. WannabeOwner

    WannabeOwner Member

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    Unless it is a company car - the 100% first year writeoff helps the man-maths. High mileage also helps - 25,000 miles a year is something like £4,000 of fuel at 30 MPG and 2.500 at 50 MGP against £400 for off-peak electricity (and some charging at Work + Superchargers and Home reduces that still). Interesting question for anyone using private car for work, and able to charge fixed cost per mile (based on ICE vehicle costs)
     
  4. J1mbo

    J1mbo Member

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    Buying as a company car through a business opens up some nice benefits over an ICE bought for the same purpose, but if it is a personal car and you need to find fuel savings to justify the cost then maybe it's not a good idea, because fuel savings depend on usage, and usage drives depreciation.
     
  5. WannabeOwner

    WannabeOwner Member

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    I wonder if that may change with EVs? Status Quo is probably the most likely influence, of course, but in practical terms there is much less to wear out on an EV (I read that we might get high mileage drivers achieving a million miles in a Model S, for example). My wife changed her ICE every 3 years because she does 25,000 miles a year and at 75,000 miles we started to worry about mechanical issues disrupting her journeys ... with EV we are expecting to be able to keep vehicle much longer (provided that the technology is not leapfrogged, of course).

    Hmmm ... passing thought ... there will always be folk that want Latest & Greatest, so will be passing their existing vehicles down to 2nd hand market, but what if a significant number decide to hang on to them (because they are reliable); that would reduce 2nd hand stock, and reduce new-car purchases (unless previous 2nd hand buyers are forced/choose to buy new, instead)
     
  6. Dan43

    Dan43 Member

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    It is a fair observation and I did wonder, if a Tesla S or X gave the user who choose to do so, over 10 years+ of fairly fuss free driving, and the fact ICE Manufacturers expect a change of a car every 5 years on average, does the actual cost per mile or cost per month ownership come down somewhat?

    If buying a £64K new ICE car the depreciation hit, fuel, maintenance, repairs, tyres when applying man maths we get a cost of ownership per month for say 3 or 5 years. If the same ICE car cost you £750 per month to own and run what would the equal maths be for Tesla S or X.

    Thinking aloud but if the total cost per month (or mile) comes under £400 overall then a Tesla, over a longer owning time frame, could prove more cost effective comparing to the equivalent ICE?

    Getting calculator out... :)
     
  7. Dan43

    Dan43 Member

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    Off to see the X this weekend on their show & tell roadshow for the X, but I get a test drive of a Model S at the same booking so will get a good feeling for the car hopefully.

    At around £60-64K for 60S-60DX funny I would never consider an ICE car at this price, I'm more in the £20-40K bracket depending on car/finance/spec etc but for a Tesla I am prepared to look at buying in on PCP at £60-64K, something I would never entertain on ICE, wonder if anyone else is the same?
     
  8. WannabeOwner

    WannabeOwner Member

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    For me: Yes and No. Used to own high performance turbo-nutter-bastards, then went all-Eco and switched to VW BlueMotion (yeah ... got stitched up by lying-cheaters, pissed about that and will never own another from VW stable). So graduated from caring, to not-caring about parking dents and stone chips etc. whilst in the £20-40K price bracket for a decade or so, and now back again to caring (car is wrapped, and wife won't take it to anywhere she has to bay-park ...). Had to do a bit of chin-stroking to decide to go back to top-draw priced motor though. (hehehe ... "motor" .... I think I might use that slang more :p)

    Went for a test drive. Fatal! Wound up with P90D ... best man-maths I ever did!!, along with stock phrase "couldn't afford not to have it" :)

    Part of my thinking was:

    I'd definitely had a hankering for a "supercar" - probably Ferrari, I love their noise. But ...
    ... two-seat no luggage space impractical, so would have to be a high-day & holiday 2nd car. That would make it a Could-do but Wouldn't-do for me.

    For me Tesla-S is an everyday supercar. 5 seats, load of luggage space, great Grand Tourer. Put your foot down and its got supercar performance. No throaty-roar though ...
    ... but as it turns out I have found that I like "ultra silent" stealth mode when less than 10 MPH, and the turbine-engine sound of the motor spinning up does it for me!

    There's only one outcome from that!!
     
  9. T90KWH

    T90KWH New Member

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    It's not only the fuel savings (which, I agree, cannot justify the capital outlay) but (i) if you commute to London, much greater saving on Congestion Charge - now £10.50 per day (£11.50 if not using autopay) vs. £0 for an all electric car, and (ii) Vehicle Road Tax = £0 for electric car, to feed into the 'is it a good financial decision?' question.

    However, I agree, for most (perhaps all) it is not an economic decision, but an indulgence.
     
  10. Dan43

    Dan43 Member

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    Looking like a cancelled order may come my way, from looking at S60 basic zero options to now thinking about an S75D with a few options ticked.
     
  11. cheekychappie

    cheekychappie Member

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    Hi, what is the set up you have to power the car totally from solar? I a looking at having panels installed in the garage roof and also looking at the Tesla wall battery, but didn't think this would be enough to charge the car?
     
  12. WannabeOwner

    WannabeOwner Member

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    I think that unless you are charging during the day (seems more likely that most car owners will be at work ... with their car!) then stuffing any excess PV generated power into the Grid, and then using off-peak (surplus ... probably) power to recharge the car in the middle of the night is a reasonable "eco" solution.

    Seems to me to be a CON that Electricity Utilities pay 50% of the generated output as presumed "exported amount" as most people will not be at home during the working day when sun is shining brightly and consequently will be using close to 0%, and exporting 100%. I work from home and have lots of computers churning away ... so I'm Alright Jack.

    My priorities have been / are:

    Reduce energy footprint (starting nearly a decade ago we managed to reduce by around 50% our usage of all of Electricity, Heating Oil, Personal Transport Fuel and Water)

    Install whatever renewables make sense - we replaced Oil Boiler with Wood Boiler, and have Solar Thermal and PV. I don't think my wind is good enough!!, sadly.

    Make changes until the house is Zero energy (good luck with that as a retro-fit! we built a Passive House extension that we can hibernate into in the winter so that the main house energy use is dramatically reduced [the energy to heat passive house in Winter is pretty much zero])

    My final step, and no plans yet, will be to store surplus energy to use at peak times / avoid exporting anything to the grid (if they still want to pay me 50% unmetered FIT payment that's up to them ...)
     
  13. Dan43

    Dan43 Member

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    I'm in this world for harvesting power from solar panels and charging a Model S fully, but storage seems small at the moment, the power wall is 6kW which may just cover a house for 1 days use (average is 9kW according to research).

    75D is 75kW so would need over 10 power walls to keep it topped up via solar energy.

    I read BMW are using old i3 batteries at 22kW for their home storage system

    Has anyone done the research to find a system that harvests enough energy to keep a Tesla S or X fully running?
     
  14. Saghost

    Saghost Active Member

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    Well, there's a guy in New Jersey who bought the battery packs from four or five wrecked Teslas and pulled them apart and rewired them to make a massive storage system for his home.

    Most folks aren't likely to need anything close to what you're describing, though. Unless you drive the car 200+ miles every day, you don't need to be able to charge for 200+ miles every night - you just need enough storage/charging to somewhat exceed your average daily usage.

    If you do drive 200+ miles per day, you're going to need a rather remarkable solar system...
     
  15. Dan43

    Dan43 Member

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    True, and until I get my weekly/monthly average use I can't predict what I will do. Plus for my longer journeys I just need a charge to get me to the SuperCharger that is being used (I have a weekly 260 mile return run for work to do, plus local use while there)

    That storage by the New Jersey guy is pretty OTT will check for his posts, thanks.
     
  16. GSP

    GSP Member

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    That "New Jersy guy" (WK057) is pretty OTT. He also retrofitted autopilot to a non-autopilot car just to prove he could do it. It was a ton of work, and he says he will never do that again. :)

    The way I look at dropping £64k on a new car to "save money on fuel" is that if you are shopping for £64k cars, why not get the best one? You also save a ton of money on fuel (especially so in the UK vs. NA), and the payback is immediate compared to all the other (non)competitive £64k cars.

    GSP
     
  17. WannabeOwner

    WannabeOwner Member

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    You could do some theoretic sums based on historical mileage (although knowing daily journey-length would help, to gauge max charge on an average worst-case day)

    I'm still struggling with storage being useful, at all, until installed renewable capacity approaches a very significant proportion of usage, until that point it seems to me to be better to turn off some geriatric generation when the wind is blowing hard on a very sunny day!, but clearly Elon thinks there is a huge market for static storage and I'd back him rather than me any day ...

    Storage for smoothing-supply I can understand - some modest batteries and smart meters in order not to have to fire up extra gas turbines when there is an ad-break during a major sporting event / Soap - but I'm struggling with it being worthwhile to store my own PV electricity from Day to Night in order to charge my car after I get back home. The grid is pretty efficient, so stuffing my PV electrons into the grid during the day, for Industry to use, and buying them back at night off-peak when there is surplus generating capacity, seems like the same as owning a battery to me - except it has zero capital outlay and I get FIT rebate payments for my exports :p
     
  18. Saghost

    Saghost Active Member

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    The main reason I want some battery storage at home is self sufficiency - if something happens to my local substation or regional grid, I want to have at least a limited amount of power available for refrigerators and running furnaces and the like - and a set up that will keep the solar panels generating power for the bigger things.
     
  19. Dan43

    Dan43 Member

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    I guess I wan't to be self sufficient and create my own electricity to save on the bills each month, if I could also charge up the Model S to the levels I use it from the same supply all the better.
    How realistic it is these current moments in time is what I am researching
     
  20. WannabeOwner

    WannabeOwner Member

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    Does PowerWall provide the equivalent of a UPS (uninterrupted supply) if there is a power cut? We have UPS on some bits of computer equipment, and most of our power cuts are just a few seconds - long enough to force an annoying reboot of anything not on a UPS. A whole-house UPS, via PowerWall, would indeed be great!

    We have a socket on the wall for a generator, so in a prolonged outage we can connect the whole house to generator. We have to turn off 99% of devices in the house, as the generator is relatively small; in UK we also have to throw an isolating switch - to disconnect the house from the grid - before connecting the generator (otherwise generator could power the grid, and electrocute a linesman who was repairing the fault). Also, PV doesn't generate, here, in a power cut (presumably for the same reason), so I need a generator running in order for PV to also run :) PowerWall might help in that situation (avoiding the need for a Generator maybe?)

    Having a socket for generator was done to avoid us running an extension lead from generator to TV and Heater, in winter ... so just laziness / convenience really, but making sure enough of the house is turned off to get under the generation limit is quite a challenge. I probably should throw the breaker for "most" circuits and designate some "if on generator" circuits to be left on.
     

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