When are you going fully electric?

Soldato
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Given how much these cars cost and are meant to be ‘premium’, to be removing things like parking sensors...
It happens - BMW, Mercedes, Audi and especially Porsche are much worse. You can spend £140k on a Taycan Turbo S and still need to drop extra on heated steering wheel, parking assist, folding mirrors, ambient lighting etc..
 
Associate
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Those figures look low to me. Have you allowed for the inefficiency in the charging process?

A lot of people are shocked when they realise that it actually takes 82kW of electricity to charge their 74kW battery.

Tesla Superchargers seem to be about 90% efficient so for every 90kW in the car you actually pay for 100kW. So you need to factor that in. And then once you go above 80% you’re into Tier 2 charging so 0-100% is a lot more expensive. So Tesla 0-80% I reckon is £15.79 and Tesla 0-100% is £21.81 and you might be looking at wait fees at some popular Supercharger locations because they really want you off those chargers at 80%.

Tesla at home is slightly less efficient in my experience so for every 100kW in you get 88kW in the battery. And then it’s down to your electricity providers rates. For me 0-100% would cost 12.9p/kW flat (Scottish Power) and that would be £10.85. If I could get a 0-100% charge on a M3 Performance for £3.75 I’d be dancing.

Tesla Superchargers only charge for the actual energy added to the battery- so regardless of efficiency you only pay for what you get.

Also Superchargers in the UK don’t charge extra for going over 80% (though in reality you don’t often do this - I have done though). They also don’t charge any wait fees. The only additional fee is an “overstay fee” if you finish charging and don’t leave, and the location is over 50% busy. Even then, they send a notification to your phone to ask you to move once your charge is complete.

So it’s not possible to pay more than £13.80 for a 0-80% charge at a Supercharger or £17.25 for a 0-100% charge in an M3P, unless your leave the car there once charged, blocking a charger, ignoring the notifications so getting an overstay fee.

My home charger is between 98-99% efficient and I pay 5p per kWh so I could charge an M3 performance from 0-100% for £3.75 (say £4 allowing for 2% losses).
 
Soldato
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Where do you draw the line about what is a premium feature that should be paid for as an extra, and a standard feature that you'd expect on every model?

Things like parking sensors, and a reversing camera aren't premium features any more, they might have been 10 years ago but I see them as a part safety feature. Heated gubbins are a different matter, not everyone, wants/needs heated seats/steering wheel/wipers etc. so I get why they can be charged as an extra.
I think that BEVs have raised the bar with respect to what should be included as standard since they needed to prices the cars at the upper end of the market, thus you expect certain features to be included on most without having to spend a fortune on extra's.

Sometimes I think it costs them more in time to take away some of the options, unless they do a Tesla and just software lock them.
 
Associate
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You'll get heat loss, and OBC inefficiencies as well.
True- but we’re talking peanuts difference a that point. Doesn’t matter if it costs £3.90 for £4.10 - it’s an insignificant amount.

Supercharging is considerably more expensive than home charging - though still much cheaper than buying petrol.
 
Soldato
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True- but we’re talking peanuts difference a that point. Doesn’t matter if it costs £3.90 for £4.10 - it’s an insignificant amount.

Supercharging is considerably more expensive than home charging - though still much cheaper than buying petrol.

I was just confirming that you'll lost about 10% in real terms, as you said peanuts in home charging costs especially on an EV tariff, but adding all those extra kWh up over a few years is significant.
 
Associate
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I was just confirming that you'll lost about 10% in real terms, as you said peanuts in home charging costs especially on an EV tariff, but adding all those extra kWh up over a few years is significant.

It’s about 2% but either way- if £0.10 on a charge / £10 over the course of a year is significant it’s probably best to not spend £50k+ on a car :)

Last 2 charges:

 
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Associate
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Those figures look low to me. Have you allowed for the inefficiency in the charging process?

A lot of people are shocked when they realise that it actually takes 82kW of electricity to charge their 74kW battery.

Tesla Superchargers seem to be about 90% efficient so for every 90kW in the car you actually pay for 100kW. So you need to factor that in. And then once you go above 80% you’re into Tier 2 charging so 0-100% is a lot more expensive. So Tesla 0-80% I reckon is £15.79 and Tesla 0-100% is £21.81 and you might be looking at wait fees at some popular Supercharger locations because they really want you off those chargers at 80%.

Tesla at home is slightly less efficient in my experience so for every 100kW in you get 88kW in the battery. And then it’s down to your electricity providers rates. For me 0-100% would cost 12.9p/kW flat (Scottish Power) and that would be £10.85. If I could get a 0-100% charge on a M3 Performance for £3.75 I’d be dancing.

my M3 performance on octopus go would cost around £4.10 for a full charge. 5p per kWh. Obviously a full charge from 0 isn’t possible in the 4hr window but would be my running costs as it would charge in that period. Say from 40-80%. Not that I am doing many miles at the moment
 
Soldato
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some 'inefficiency' is mitigated by pre-conditioning (ie. energy) on the way to the supercharger too
.. if you monitored battery temperature you could drive faster/slower - as needed
 
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some 'inefficiency' is mitigated by pre-conditioning (ie. energy) on the way to the supercharger too
.. if you monitored battery temperature you could drive faster/slower - as needed


The car does this itself- when you’re heading to a supercharger it says “preconditioning for supercharging” on the screen. This is mainly for speed though to ensure you can charge as fast as possible when you reach the charger.
 
Soldato
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some 'inefficiency' is mitigated by pre-conditioning (ie. energy) on the way to the supercharger too
.. if you monitored battery temperature you could drive faster/slower - as needed

You can’t beat physics. If you put 1kW into a battery you need to put more than 1kW through the charger. And you pay for it. The truth is we generally don’t look too hard at the bill. The bill says you got maybe 35kW and in the car your battery went up by maybe 32kW. By Pre-conditioning the battery Tesla just make it as fast as possible. They don’t care about efficiency because you’re paying for ALL the electricity used anyway.
 
Soldato
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my M3 performance on octopus go would cost around £4.10 for a full charge. 5p per kWh. Obviously a full charge from 0 isn’t possible in the 4hr window but would be my running costs as it would charge in that period. Say from 40-80%. Not that I am doing many miles at the moment

But you’re just kidding yourself. You can’t charge a 74kWh battery in 4 hours at home. Your home charger at absolutely maximum speed can put 7.4kW per hour into your battery and to do that it uses more than 7.4kW/hr because of inefficiency is the charging process. You’re taking AC power from the mains and converting that to DC in the car’s charger and you also lose a bit in heat because as the battery charges it heats up. So let’s be kind and say that you put 7.4kW/hr in your Tesla you need 8kW per hour from the grid. At your special 5p rate you’ll use 32kW and that will put 29.2kW into your battery. So that’s 40% of your battery. The other 60% - 44kW (48kW input energy) will be at the non-special rate of 14p/kW so that’s £6.16 on top of the £1.46 so the real cost of a 0-100% full charge on Octopus Go is £7.62. And in my fixed 12p/kW tariff when I can charge any time it’s £8.88. And that’s my electricity cost for the car. Across the whole house usage through the day (especially working from home) Octopus Go is more expensive for me.

My aim in this is to give the person who asked the question realistic information so they can make an informed choice about buying a vehicle. By telling people it’s going to cost them £3.75 to charge the car from 0-100% they’re being VERY disingenuous.
 
Soldato
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You can’t beat physics. If you put 1kW into a battery you need to put more than 1kW through the charger. And you pay for it. The truth is we generally don’t look too hard at the bill. The bill says you got maybe 35kW and in the car your battery went up by maybe 32kW. By Pre-conditioning the battery Tesla just make it as fast as possible. They don’t care about efficiency because you’re paying for ALL the electricity used anyway.

Tesla Superchargers charge per kWh delivered to the car. Losses during the process are not relevant to how much the user pays.
 
Associate
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It's true that you can't charge from 0-100 in one 4 hour window on Octopus Go. However, in the 9 months since I switched to Octopus Go, I have never needed to charge outside of the overnight 4 hour window.

My car is an SR+ so only 50kWh battery, but when I arrived home once day with 4% battery, I just added approx 28kW that night (upto 60% charged). Then the next night I charged up to 80%.

If I'd needed to go up to 80% in one night I'd just have paid "full price" for the extra 10kW - a hefty £1.30 !
 
Soldato
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Tesla Superchargers only charge for the actual energy added to the battery- so regardless of efficiency you only pay for what you get.

Also Superchargers in the UK don’t charge extra for going over 80% (though in reality you don’t often do this - I have done though). They also don’t charge any wait fees. The only additional fee is an “overstay fee” if you finish charging and don’t leave, and the location is over 50% busy. Even then, they send a notification to your phone to ask you to move once your charge is complete.

So it’s not possible to pay more than £13.80 for a 0-80% charge at a Supercharger or £17.25 for a 0-100% charge in an M3P, unless your leave the car there once charged, blocking a charger, ignoring the notifications so getting an overstay fee.

My home charger is between 98-99% efficient and I pay 5p per kWh so I could charge an M3 performance from 0-100% for £3.75 (say £4 allowing for 2% losses).

I don’t know where you’re getting your figures, but they don’t add up. You don’t pay 5p/kW 24/7. You pay 5p/kW for a 4 hour window and you pay at least 14p for the rest of the time. So your £3.75 figure is just not true. And I can’t be bothered to refute the rest of your post but it’s about as accurate as your £3.75 for a full charge at home claim. Sorry, but you’re MILES out.
 
Soldato
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Don’t worry blun, I read your post in context. Don’t let the posts above frustrate you. :)

i can charge my car for only a little more aswell from home. As I don’t use a full battery every day like most people. If consumption did increase first change to do would shift to 5.5p Go Faster for 5 hours starting 8:30pm.

Weird narrative again above that got decimated last time I look at the numbers when challenged on the “special tariff” - I don’t know what you have to be doing “working from home” for the simple maths to not pay off with Octopus tariffs.

I assume a baker or growing weed in the loft? :D

I’m tempted to drive to ASDA several times and charge for free just so I can say a full charge costs £0 and watch the fireworks of a QWERTY warrior.
 
Soldato
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Don’t worry blun, I read your post in context. Don’t let the posts above frustrate you. :)

i can charge my car for only a little more aswell from home. As I don’t use a full battery every day like most people. If consumption did increase first change to do would shift to 5.5p Go Faster for 5 hours starting 8:30pm.

Weird narrative again above that got decimated last time I look at the numbers when challenged on the “special tariff” - I don’t know what you have to be doing “working from home” for the simple maths to not pay off with Octopus tariffs.

I assume a baker or growing weed in the loft? :D

I’m tempted to drive to ASDA several times and charge for free just so I can say a full charge costs £0 and watch the fireworks of a QWERTY warrior.

Nice I-PACE colour choice BTW. I used to have a black one. It was beautiful when clean... For 30 minutes after washing. :D
 
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