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Charging cost, am I thinking about this correctly?

I'm due to pick up the car next week and time is running out for me to bottle out, so I'll likely flood these forums with some last minute quick fire questions, which can of course be ignored :cool:

I'll be pretty much public charging as per my other posts and while I will have a backup solution of the slow 3 pin charger and extension cable, if I can avoid using it, I will do.
In Scotland there are a few semi local free charging options that I'll be relying on but I am a bit concerned that some others are quoting prices as high as 45p/ kwh, so how does this work exactly?

What does that equate to when going from say 20-80%, (its a LR I'm due to get). Am I right in thinking that would be 60% of say an 80kwh battery(I've read both 75 and 80).

If we assume that it is an 80kwh battery and we're charging 60% (20%-80%), then that would be 48kwh (call it 50kwh), am I right so far?

so at a 50kwh charger (again, some in close range to me are listed as 44kwh and some 50kwh), we'll go with the latter for ease of calculation. Now assuming I get that speed through the duration of the charge, I would be charging for an hour to make the 50khw required to meet my 60% and the cost would be 50x0.45=£22.50
I'm not too sure what to make of that, if that was a weekly affair, I'd be saving very little if anything over my current car (currently enjoying 22mpg) so I'm really curious as to how far this 60% will get me, at the calculated cost.
I've already been advised in other posts that I wont manage more than a week without a charge which kind of means, this is the type of running costs I could be looking at for a sub 100 mile weekly commute. Now understandably, this is not by any means the most efficient way of charging an EV, given that home charging and free public charging is obviously better but should neither of these options be available, it would be good to know what I'm getting in to in a worst case sense.

thanks in advance...
 
I think your calculations are right. Most savings come from charging at home unfortunately. I think most try to get their off peak cost as low as possible. I think mine is currently 10p, some even get 5p with Octopus. This is where you are saving. I mean I'm getting about 25-30mpg on current car and its drinking petrol and costing me a fortune. swapping to EV was a no brainer at the moment.
 
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The issue you'll have is that depending on the weather conditions the car will be more or less efficient. This is partly the battery needing warming/cooling, but also the cabin, and things like the headlights and wipers.

This can mean that in summer you can easily beat 4miles per kWh, and in the winter be lucky to get 2miles per kWh. My worst in the year and a bit I've had it has been 456Wh/mi (so a smidge over 2 miles per kWh), and best 214Wh/mi (so close to 5miles per kWh).

So lets take the worst case, 2 miles per kWh. So your 48kWh would get you 96 miles and yes, cost you £21.60

But best case you'd get nearly 240 miles for that same price.

I'd defo avoid public chargers, and use 3 pin if you can.
 
I'm due to pick up the car next week and time is running out for me to bottle out, so I'll likely flood these forums with some last minute quick fire questions, which can of course be ignored :cool:

I'll be pretty much public charging as per my other posts and while I will have a backup solution of the slow 3 pin charger and extension cable, if I can avoid using it, I will do.
In Scotland there are a few semi local free charging options that I'll be relying on but I am a bit concerned that some others are quoting prices as high as 45p/ kwh, so how does this work exactly?

What does that equate to when going from say 20-80%, (its a LR I'm due to get). Am I right in thinking that would be 60% of say an 80kwh battery(I've read both 75 and 80).

If we assume that it is an 80kwh battery and we're charging 60% (20%-80%), then that would be 48kwh (call it 50kwh), am I right so far?

so at a 50kwh charger (again, some in close range to me are listed as 44kwh and some 50kwh), we'll go with the latter for ease of calculation. Now assuming I get that speed through the duration of the charge, I would be charging for an hour to make the 50khw required to meet my 60% and the cost would be 50x0.45=£22.50
I'm not too sure what to make of that, if that was a weekly affair, I'd be saving very little if anything over my current car (currently enjoying 22mpg) so I'm really curious as to how far this 60% will get me, at the calculated cost.
I've already been advised in other posts that I wont manage more than a week without a charge which kind of means, this is the type of running costs I could be looking at for a sub 100 mile weekly commute. Now understandably, this is not by any means the most efficient way of charging an EV, given that home charging and free public charging is obviously better but should neither of these options be available, it would be good to know what I'm getting in to in a worst case sense.

thanks in advance...
I've used Public Charging in Scotland for over 2 years and generally it's been fine but when the Chargers break it can be some time before they get fixed so it's a good idea to have a Plan A, B and even C. Around 50% of Local Authorities are free and the other 50% now charge but they all seem to do so differently so you will need to work out what's Local to you.

I think your Man Maths are broadly correct but I think the 0.45p figure is on the high side but again check Locally, someone on here posted a list of Local Authority charges so I suggest you try to find that using the Search Function.

Public Charging can work for some of us but it's not for everyone.
 

Dilly

Active Member
Feb 24, 2020
2,869
2,306
Norfolk
If you have the ability, charging at home is the way to go. I don’t do many miles these days. My journeys are all pretty short and therefore cost almost double the battery power.
on the plus side my Octopus 4 hour overnight window is just 5p/kWh. This only gets used in winter when solar generation is low
 

muster39

Member
Nov 13, 2021
43
27
UK
Based on current standard variable capped electricity costs I reckon under normal conditions my M3 LR mileage costs are around one third of a medium sized petrol car. (Now the weather is colder the charging costs are a bit higher).

I think that another issue to consider is that on public chargers you may need to move the car once it’s fully charged. Blocking a charging space when the car is fully charged would not be fair to other EV users and there may be idling fees to discourage this. If your public charging location isn’t too far away then that may not be a problem. If not you may need to consider the convenience factor.
 

init6

Active Member
Oct 16, 2020
1,469
904
Scotland
45p/kWh is astonishingly expensive for Scotland. Even superchargers are 'only' 37p at the most. I've driven 8.5k miles this year and my total charging costs are £100. Which part of Scotland are you in? Generally the East coast are charging while the West are still mostly free. Even when they do charge, 19p/kWh isn't unheard of.

Edit: There should be a post about the costs for Chargeplace Scotland. Try the search bar - it works :)
 
Good thread. To me the whole idea that EV's are cheaper to operate because they are electric seems to be a disappearing sentiment, especially to those who are unable to charge at home, and may get just a token amount of free public charging. I almost always charge at home for 12 cents per kW hour, otherwise it's free at superchargers for as long as I own the vehicle, so I am just becoming aware of this issue. Unfortunately, all the public charging providers need to do is keep the price a bit below or even equal to fuel prices. What a great opportunity for them to make more money!

My fear is that this trend will continue, and EV's will be as expensive to fuel as ICE vehicles - that somehow regulators will be able to charge you more at home if you are charging your car versus heating your house.

Am I being paranoid?
 

Medved_77

TM3 SR+ | MSM+Black | No FSD
Supporting Member
Jan 20, 2020
2,138
2,250
Scotland
someone on here posted a list of Local Authority charges so I suggest you try to find that using the Search Function.
 
Good thread. To me the whole idea that EV's are cheaper to operate because they are electric seems to be a disappearing sentiment, especially to those who are unable to charge at home, and may get just a token amount of free public charging. I almost always charge at home for 12 cents per kW hour, otherwise it's free at superchargers for as long as I own the vehicle, so I am just becoming aware of this issue. Unfortunately, all the public charging providers need to do is keep the price a bit below or even equal to fuel prices. What a great opportunity for them to make more money!

My fear is that this trend will continue, and EV's will be as expensive to fuel as ICE vehicles - that somehow regulators will be able to charge you more at home if you are charging your car versus heating your house.

Am I being paranoid?
I can’t speak for the US, but in the UK with the increase in electricity costs over the last year, we will likely reach parity in the cost of electricity to diesel per mile.

My old SUV cost £0.20 / mile to run. On an EV, I’m averaging £0.08 / mile when charging at home and £0.15 / mile when using public chargers. We are likely to see another jump in electricity prices in the UK so I can foresee public chargers reaching £0.20/mile next year.

So yes, if you can’t charge at home or don’t have access to superchargers or low cost public chargers, then parity is on its way 😪
 
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Sounds to me like a "Free With Purchase" type of deal.
 
Good thread. To me the whole idea that EV's are cheaper to operate because they are electric seems to be a disappearing sentiment, especially to those who are unable to charge at home, and may get just a token amount of free public charging. I almost always charge at home for 12 cents per kW hour, otherwise it's free at superchargers for as long as I own the vehicle, so I am just becoming aware of this issue. Unfortunately, all the public charging providers need to do is keep the price a bit below or even equal to fuel prices. What a great opportunity for them to make more money!

My fear is that this trend will continue, and EV's will be as expensive to fuel as ICE vehicles - that somehow regulators will be able to charge you more at home if you are charging your car versus heating your house.

Am I being paranoid?
Yes
 
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LoudMusic

Active Member
Jul 21, 2020
1,419
1,657
Arkansas
Good thread. To me the whole idea that EV's are cheaper to operate because they are electric seems to be a disappearing sentiment, especially to those who are unable to charge at home, and may get just a token amount of free public charging. I almost always charge at home for 12 cents per kW hour, otherwise it's free at superchargers for as long as I own the vehicle, so I am just becoming aware of this issue. Unfortunately, all the public charging providers need to do is keep the price a bit below or even equal to fuel prices. What a great opportunity for them to make more money!

My fear is that this trend will continue, and EV's will be as expensive to fuel as ICE vehicles - that somehow regulators will be able to charge you more at home if you are charging your car versus heating your house.

Am I being paranoid?

Yes you are being paranoid. There are too many ways to mask how the electricity is being used, even if they require installation of some crazy hardware in houses. So they won't be bothering with that. And besides, the only product the electric company sells is electricity. Selling more of it isn't a problem for them.

But you are correct that charging EVs is becoming more expensive at commercial charging locations. Those prices have slowly crept upwards over the past four years. I would absolutely not own an EV if I was unable to charge at home, and make the same recommendation to others. For me one of the top reasons for owning an EV is the convenience of charging at home. It helps that it's so cheap as well (only $0.065/kwh in the summer, $0.055/kwh in the winter).

An aside, who's your provider? I would have guessed Bee Cave was on Pedernales which is only $0.094/kwh (ish). When I lived in Austin I was southeast of you and we had Pedernales - it was fantastic. And they had an amazing usage reporting tool that logged down to 15 minute increments I think. Totally geeky and awesome.
 
My old car, a 4L V8 twin Turbo cost me in fuel 34p/mile. Add servicing and road tax and it would be 46p/mile.
The M3 LR is running at 280wh/mile, so 3.6 miles/kw. I'm 85% home charging and at present the cost is 16p/kw so the car costs 4.44p/mile. Add in some Supercharger use and over a 7000 mile year it would be 5p/mile...until March when my Scottish Power fixed tariff ends. I calculate my electricity cost will double, but it is still a big reduction on the ICE costs.

I changed from a 463 bhp ICE sport saloon to a 434 bhp EV Sport Saloon, with a fraction of the running costs.
 
Yes you are being paranoid. There are too many ways to mask how the electricity is being used, even if they require installation of some crazy hardware in houses. So they won't be bothering with that. And besides, the only product the electric company sells is electricity. Selling more of it isn't a problem for them.

But you are correct that charging EVs is becoming more expensive at commercial charging locations. Those prices have slowly crept upwards over the past four years. I would absolutely not own an EV if I was unable to charge at home, and make the same recommendation to others. For me one of the top reasons for owning an EV is the convenience of charging at home. It helps that it's so cheap as well (only $0.065/kwh in the summer, $0.055/kwh in the winter).

An aside, who's your provider? I would have guessed Bee Cave was on Pedernales which is only $0.094/kwh (ish). When I lived in Austin I was southeast of you and we had Pedernales - it was fantastic. And they had an amazing usage reporting tool that logged down to 15 minute increments I think. Totally geeky and awesome.
I have Austin Energy, phone bill says Bee Cave, so who knows I am off Cuernavaca and not in the city limits. Here we do pay a bit less for the first many kW but that always gets used up for just the basics, so at the top tier I end up at about 12.5 cents per kilowatt hour. Still a great deal compared to paying for Supercharging or third party charging. Austin Energy has a program for a flat fee that lets you use any L2 charger that gets its power from Austin Energy, most of those are 6 kW, so essentially useless unless you can stay there for hours at a time.
 
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Jason71

Active Member
May 8, 2019
4,027
4,296
Shropshire
In my experience overall the amount of Electricity I consume vs the kwh the car reports it has used while driving is about +30-35%.
You might think that sounds like a lot but take in all the factors of charger loss, cable loss, battery heating, cabin heating, a bit of sentry and I think you will find its the same for most people. the figures for usage we like to quote for usage are good only for calculating the range on a single long journey.
 

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