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Discussion Starter #1
Clearly the figures on the screen double count so are meaningless (if you use both fuels)... so I've worked out the equivalent cost of the electric (@13.5 p per kWh) in "petrol cost" and on my first half tank doing about half miles Elec I'm getting an equivalent cost of 55mpg.
Do I get a prize for being a nerd ? ;-)
 

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Yes for sure if you publish your calculations! btw does this mean the standard gauge on the GTE is incorrect? (and is this only in hybrid mode)
 

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What's the double counting? You get 1 figure of total miles covered, a figure for average petrol mpg and a figure of average mi/kWh. So you can work out how much the consumption of petrol and electricity has cost separately but I'm wondering why (and how!) convert that into an overall equivalent mpg cost?
 

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Discussion Starter #5
]

Number of Litres = 20.28 at a cost of £23.30 (£1.15per litre)
57 Kwh @ 13.5p per Kwh … cost = £7.70
321 miles… full : full (both elec & petrol)
Total cost (petrol&elec) = £31
£31/£1.15 = 26.98 (equivalent number of Litres)
0.219 * 26.98 = 5.91 (equivalent no of Gallons)
321 miles / 5.91 = 54.33 mpg (equivalent
 

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Discussion Starter #6
I reckon it double counts...
e.g. If you use Elec only it will work out 3-4 miles per Kw... And it will show 300 mpg
If you then use petrol then the miles per kw increases although you use no more Elec. Both figures will then be false, I think this is naughty of vw, especially if someone on a test drive believes the figures and buys the car with sky high expectations of economy.

I bought the car expecting about the same economy as a diesel for my driving pattern, if I use Elec more it'll be cheaper.
I bought the car because I love the way it drives not primarily to save money.
But I still want to know how economical it is.
 

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I don't think it's that bad. The way I see it, one needs to use both figures that you get from the car to find your true cost/efficiency. Using only one is the false approach, because you can't separate the input from the two propulsion systems.

Maybe VW can utilize an equivalent efficiency figure, such as MPGe, but I don't think it was properly defined and known when the GTE first came out. The more popular and better understood MPGe becomes, I'm sure they will implement it.
 

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Ah, I get you.

My calculations when comparing to my previous diesel were (with certain 'worst case's assumptions):

£5.22 per gallon diesel
Get an average 50 mpg
So 50 miles travelled = £5.22 cost

Electric - rough cost £1 per charge giving an average 20 miles driving. 50 electric miles should therefore cost £2.50

So running electric only is 52% cheaper than using fuel.

That's as far as I got whilst I was waiting for my GTE to arrive! Now that I have the car, it's interesting to get a combined cost, electric/petrol, for a comparison of real world fuel economy.
 

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The way I see it, a petrol hybrid is a mpg extender. The more e mode, the more mpg. If I can run my Passat GTE at a minimum mpg of the outgoing diesel, then I am happy. It will need much use of the limited e mode and mostly hybrid mode to do so. The cheaper petrol cost v diesel will be eaten up by cost of electric. Looks like public charging whilst out and about may be waste of time/cost. My guesstimate is my company will save a few hundred on fuel per year. I will save over £3k on BiK.
 

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Never mind the calculations, why are you paying 13.5p per kWh for electricity?!

I use brim to brim measurements for mpg, and I'm getting about 54 mpg the way I use my car.

The more you plug in during a tankful, the better that overall mpg.

My usage is changing slowly, especially now I have charging at work, so four days a week I'll use zero petrol.
 

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I bought the car hoping to save much money too. Got the chargemaster card at 7 quid a month then 9p per kWh, got the chargedev unit installed. To realise that my cost of electric at home is 16.5kWh!!!!! Ridiculous amount. I need to clearly look elsewhere.


Sent from my iPhone using Tapatalk
 

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I’ve been on holiday in Wales since Saturday the 29th, driving from Nottingham. I filled up the tank before I left and put it in Hybrid Auto mode to drive here, and I’ve charged it most nights using the granny lead at the cottage I’m staying in. We’ve been driving about quite a bit mainly in Hybrid mode with a bit of spirited GTE overtaking play on the lovely country roads and I’ve had to fill it up this morning as the needle just hit the red. This was my computer at the petrol station before I filled it with £42 of petrol (£1.19 a litre). I’m more than happy with the figures. Like I’ve seen written about this car on here many times, you have to charge it to get the most out of it. I love mine, whichever EV I buy after this has got a lot to live up to. It’s far and away the best car I’ve owned or driven
 

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Discussion Starter #13
Although,
I’ve been on holiday in Wales since Saturday the 29th, driving from Nottingham. I filled up the tank before I left and put it in Hybrid Auto mode to drive here, and I’ve charged it most nights using the granny lead at the cottage I’m staying in. We’ve been driving about quite a bit mainly in Hybrid mode with a bit of spirited GTE overtaking play on the lovely country roads and I’ve had to fill it up this morning as the needle just hit the red. This was my computer at the petrol station before I filled it with £42 of petrol (£1.19 a litre). I’m more than happy with the figures. Like I’ve seen written about this car on here many times, you have to charge it to get the most out of it. I love mine, whichever EV I buy after this has got a lot to live up to. It’s far and away the best car I’ve owned or driven
clearly you're driving has been much cheaper on this trip the mpg and per kWh figures are totally meaningless ... for example if you were getting 15 miles per kWh your range would be about 120 miles per charge ... the mpg figure will be meaningless too for the petrol.
 

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Whilst the electrification isn't entirely free mileage it is relatively at very low cost. I see PHEV's in E Mode purely as mpg extenders. Getting 65mpg on £42 @£1.19/ltr and 507 miles travelled would be perfect in my book for a petrol v's diesel mpg
 

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Night Blue Golf GTE Nav
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Although,

clearly you're driving has been much cheaper on this trip the mpg and per kWh figures are totally meaningless ... for example if you were getting 15 miles per kWh your range would be about 120 miles per charge ... the mpg figure will be meaningless too for the petrol.
Hardly meaningless figures on the MPG. I’ve been charging for free at the cottage I’m staying at so the 68mpg is correct as the average petrol consumption in hybrid mode. The KWh figure is a weird one as it seems to include the petrol consumption but that’s irrelevant to me. Can anyone explain the KWh figure?
 

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Night Blue Golf GTE Nav
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Whilst the electrification isn't entirely free mileage it is relatively at very low cost. I see PHEV's in E Mode purely as mpg extenders. Getting 65mpg on £42 @£1.19/ltr and 507 miles travelled would be perfect in my book for a petrol v's diesel mpg
Exactly. Also no road tax and congestion charge. And the short range journeys I do in the evenings like going shopping, taking the other half to work at the weekends are done in pure electric mode which costs me about 80p for 25 Miles. That’s the MPGe equivalent cost of 161mpg at £1.15 per litre. I’ll take that anyday. When I filled it back up before I left for Wales I had to put £8 in to get it to full. It had been 2 weeks since I’d last filled it up. £4 a week in petrol is not even a gallon and I do over 100 miles a week charging it 2 or 3 times. That’s why I drive a GTE
 

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Hardly meaningless figures on the MPG. I’ve been charging for free at the cottage I’m staying at so the 68mpg is correct as the average petrol consumption in hybrid mode. The KWh figure is a weird one as it seems to include the petrol consumption but that’s irrelevant to me. Can anyone explain the KWh figure?
I agree that it is hardly meaningless, especially in your case with the free charging. :D

In order to make sense of that screen, all you have to acknowledge is that it is a car with two propulsion systems. Both work almost inseparably, that is why VW can't provide a single figure. On the other hand, the car has three measured values: trip distance, petrol used and electricity used. And from these it is easy to calculate the two values that you see on that screen: mpg figure is the trip distance / petrol and the mi/kWh is the trip distance / electricity used. If you want to know how much a certain trip is costing you, you have to take both petrol and electricity used.
 

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Night Blue Golf GTE Nav
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I agree that it is hardly meaningless, especially in your case with the free charging. :D

In order to make sense of that screen, all you have to acknowledge is that it is a car with two propulsion systems. Both work almost inseparably, that is why VW can't provide a single figure. On the other hand, the car has three measured values: trip distance, petrol used and electricity used. And from these it is easy to calculate the two values that you see on that screen: mpg figure is the trip distance / petrol and the mi/kWh is the trip distance / electricity used. If you want to know how much a certain trip is costing you, you have to take both petrol and electricity used.
Yes I agree. What it should do is separate the true Electric driven only miles. The mpg figure is correct if you are charging for free, but I’m only paying about 80p for a full charge which drained over the 147 mile drive to Wales so it’s hardly misleading cost wise anyway as it’s only 0.5p a mile or thereabouts. The problem with the KWh figure is that it adds the distance when you are in regen as well which isn’t using electricity but generating it and gives a 99.9kw per mile reading a bit like the 300mpg figure, the maximum it will show.
 

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Bottom line is that the more you charge it, the longer a tank of fuel lasts.

The miles per kWh figure is technically correct, in that it tells you how far you've travelled on each kWh, but I agree it's meaningless.

I just use the brim to brim measurement of mpg, and track it on an app, and currently it's 64 mpg. That's charging at work and a weekly 310 mile round trip sometimes with charging at the halfway point.
 

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I too have a spreadhseet, because I agree that the figures are meaningless unless it records distance on electric and distances on petrol. Annoyingly, it obviously does record that for a single journey, as you can see a %age on the blue screen.

Anyway, your overall efficiency will massively depend on the ratio of electric miles to petrol miles. My daily commute is 42 miles, and I usually reckon about 24 are electric. I've also done several 300 mile trips with no chance to charge, which will have ruined my average a little bit. Over 19410 miles, I've averaged 8.75p/mile which gives an equivalent of 55.5mpg when converted back to fuel at the average cost over 18 months.

Probably not much better than a diesel overall, but it's so much nicer driving the GTE around.
 
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