EV charging costs and calculation - Real world example. Check my figures?

Herzlos

The problem with charging everything will more or less take care of itself as the demand and technology improves.

You sound like you're expecting every parking space in the country to be able to provide rapid charging every day at some point but the fact is that it's just not necessary.

Those rows or cars on terraced streets must go somewhere else at some point, right? The owners must use them to commute, shop, dine out or whatever. 
The more it's used the more likely it is to be somewhere with charging, and the average car will only need charged once or twice a week.

DrEskimo

Bachelorplace said:

DrEskimo said:

I'm not sure why you don't you think it would be suitable even with home charging then?

You wouldn't have needed to use any public charging and would have had it 100% each morning, including the day it was collected.

Here's how much it costs me each evening (the hour at 14:00 was to take advantage of a free 'power hour' offer I get from Octopus):

THAT Is amazing... how do I get one of these separate car only tariffs... does it take a feed from the mains box and split off the usage?

If I knew how much I was spending that would be amazing. 

That said... what charger have you got? this looks like a 7?

Doesn't matter so much how many miles one is going either. 

Does your car automatically do the stop at 80% thing?

This is the Octopus GO tariff. Just need to apply and get a SMETS 2 meter installed and you're good to go.

My current fixed tariff ends in June, where it will increase from £0.05/kWh to £0.075/kWh between the hours of 00:30-04:30.

That's a screen shot from my charger App, so it knows the exact charge it's delivering. The mains bit doesn't know if it's electricity to my car, dishwasher or TV. Just delivers power and the time of day determines the cost.

That's right, mines a 7kW charger

I cant set the charge limit on my Zoe but it has a schedule charging function, as does my charger through the app. I use the car one (either through the cars App, or through the car it self).

Freecall

You will find that most EV owners do something similar.

Unfortunately as DrEskimo says, the 5p/unit price we have enjoyed for several years is going up to 7.5p but that is just the way it is.

Still miles cheaper that petrol/diesel for an ICE.

Petriix

DrEskimo said:

Bachelorplace said:

DrEskimo said:

I'm not sure why you don't you think it would be suitable even with home charging then?

You wouldn't have needed to use any public charging and would have had it 100% each morning, including the day it was collected.

Here's how much it costs me each evening (the hour at 14:00 was to take advantage of a free 'power hour' offer I get from Octopus):

THAT Is amazing... how do I get one of these separate car only tariffs... does it take a feed from the mains box and split off the usage?

If I knew how much I was spending that would be amazing. 

That said... what charger have you got? this looks like a 7?

Doesn't matter so much how many miles one is going either. 

Does your car automatically do the stop at 80% thing?

This is the Octopus GO tariff. Just need to apply and get a SMETS 2 meter installed and you're good to go.

My current fixed tariff ends in June, where it will increase from £0.05/kWh to £0.075/kWh between the hours of 00:30-04:30.

That's a screen shot from my charger App, so it knows the exact charge it's delivering. The mains bit doesn't know if it's electricity to my car, dishwasher or TV. Just delivers power and the time of day determines the cost.

That's right, mines a 7kW charger

I cant set the charge limit on my Zoe but it has a schedule charging function, as does my charger through the app. I use the car one (either through the cars App, or through the car it self).

And of course it's not just for car charging. You must have an EV to qualify for the tariff, but then your whole house usage is charged at the same rate. 

Bachelorplace

A separate EV charging tariff that piggy backs would be the only way you can tell what you are being charged. I thought your app was car only. But you are saying this is the "draw" that the car is using and you subtract that from your normal Electric bill...have you checked that?
Last time I charged a Audi E Tron from my home plug my electric for that month went up from about £50 to about £125 I did two full charges, give or take... that made it a fortune and very hard to see what was using what. I did another post about that which you might have seen anyway. 

DrEskimo

Bachelorplace said:

A separate EV charging tariff that piggy backs would be the only way you can tell what you are being charged. I thought your app was car only. But you are saying this is the "draw" that the car is using and you subtract that from your normal Electric bill...have you checked that?
Last time I charged a Audi E Tron from my home plug my electric for that month went up from about £50 to about £125 I did two full charges, give or take... that made it a fortune and very hard to see what was using what. I did another post about that which you might have seen anyway. 

You're overcomplicating it. I get charged two fixed rates depending on the time of day:

£0.159: 4:30-00:30
£0.05: 00:30-04:30

Any electricity my house uses, regardless of whether it's the EV, the dishwasher or the tumble dryer get charged for whatever energy they use depending on the time they are used.

What I showed you was the app I can use with me EV charger. That shows me specifically what the car charger is using. I can set the prices depending on the time of days so it calculates the cost for me.

An Audi e-Tron 50 has around 70kWh battery and the e-Tron 55 has around 90kWh. So you just multiply that by your unit cost of electricity and you can get the cost of a full charge (adding around 10% for charging loses). It all depends what rate per kWh your utility company charges you, and if you have a time depending tariff, when you charge it.

MX5huggy

This April the car has covered 828 miles. I’ve used 241kWh to charge it most of those cost me 5p so £12.05 or 1.45p per mile. I got a few free kWs from my Solar PV panels. Prices are higher now for new customers and mine will go up in September by 50% to 7.5p so £18 per month. 

Freecall

DrEskimo said:

You're overcomplicating it. 

Possibly deliberately so.

Dual-rate tariffs have been around for decades, there is nothing complicated about them at all.

Bachelorplace

So have DAWs - I have been using those for decades, do you know how to edit on them?

Bachelorplace

MX5huggy said:

This April the car has covered 828 miles. I’ve used 241kWh to charge it most of those cost me 5p so £12.05 or 1.45p per mile. I got a few free kWs from my Solar PV panels. Prices are higher now for new customers and mine will go up in September by 50% to 7.5p so £18 per month. 

MX5huggy said:

This April the car has covered 828 miles. I’ve used 241kWh to charge it most of those cost me 5p so £12.05 or 1.45p per mile. I got a few free kWs from my Solar PV panels. Prices are higher now for new customers and mine will go up in September by 50% to 7.5p so £18 per month. 

How does it know what the Zappi uses..??? If it is not split??

Anyway it seems I am paying.... a staggering... 19p per KWh!!! Is this a lot? I certainly sounds like it is compared to your 7p.

It appears that I use 164kwh per month on average without a car being charged...  to your... 500kwh right?

If I had a BMW iX which has a 111kw each charge would be 111 x 19p or £21.00 per full charge. If that car does 227 miles of real world range ( source https://bmwi.bimmerpost.com/forums/showthread.php?t=1898912 ) then it might work out to be the equivalent of 85 miles per gallon if fuel is 1.62 per litre right? 

Miles 227 
Cost - £22.67
Fuel - 1.62
MPG 85
Cost per mile = 0.99p

Desiel car equivalent

Miles 227 
MPG 42
Cost £45.98 
Cost per mile = 0.202p 

Anyway...  So, either Scottish Power rip me off - or I am missing something???