Thinking of going back to EV - couple of charging questions

[samoht]

Just reading back this thread again, these two statements don't seem to align:

gotoPzero said:

my total for the month is normally around 200 miles.

gotoPzero said:

its looking like the car is going to need about 180-200kw a month.

Even an I-Pace should average 2 miles/kWh, a Tesla Model 3 probably more like 3-4 depending on the type of driving. So if you're doing 200 miles a month that's more like 50-100 kWh a month.

If so, the numbers I ran above would be different and it may not be worth having an EV tariff, unless you can also shift a fair proportion of domestic use to overnight.

There's a list of available EV tariffs here https://www.moneysavingexpert.com/utilities/ev-ene... note that the peak rate, off-peak rate and number of off-peak hours all vary between deals.

[gotoPzero]

I need to see how many miles I have done so far. But I had the car 3 weeks and charged 135kw.

A % goes on sentry mode and pre heating but at a guess I have done 350 miles in that 3 weeks. i need to check that though.

150 of those has been bringing the car home though. Will check later.

[FeelingLucky]

As an aside, the Tesla "brick"/Granny charger has interchangeable tails.
With the 32A tail fitted and a commando socket you can charge at full fat speeds (single phase 32a 7.4kw)

[gotoPzero]

FeelingLucky said:

As an aside, the Tesla "brick"/Granny charger has interchangeable tails.
With the 32A tail fitted and a commando socket you can charge at full fat speeds (single phase 32a 7.4kw)

I thought they were pegged at 4kw?

That is what I am intending to use fwiw.

[FeelingLucky]

gotoPzero said:

FeelingLucky said:

As an aside, the Tesla "brick"/Granny charger has interchangeable tails.
With the 32A tail fitted and a commando socket you can charge at full fat speeds (single phase 32a 7.4kw)

I thought they were pegged at 4kw?

That is what I am intending to use fwiw.

Standard Tesla Granny, Tesla 32A tail (about £30 IIRC)

[gotoPzero]

Even better thanks.

[FWIW]

On your usage I would say it’s not worth going to an EV tariff. I suspect the Octopus Tracker would be significantly better and with the restrictions of an EV tariff.
Also, not worth having a dedicated charger, the granny charger will be more than enough.

I have a YLR and my wife has a YRWD and even doing a lot more miles than you (20k combined) it’s marginal that we benefit from Octopus Intelligent. We average about 15p/kWh by gaming the system as described above, I believe the Tracker is around 18p/kWh.

[gotoPzero]

I am a bit confused.

Our current rate is 28.44 which is obvs 24/7.

Our house seems to use about 10kw a day ave.

The EV rate I was looking at is 30.23 in the day and 9p for 4 hrs at night. So costs me c20p a day more on EV for the house.

But on the car I am saving £1.60 per day? (assuming it takes the full 2kw x 4hrs per night)

So I am saving £1.40 per day?

Is that not right?

I had the car 19 days and have charged 160kw.
So thats 8.5kw per day.

Admitidly its currently sat on the drive at 80% soc. So some of that is in the car, so to speak.

I think my average will come back down to about 6kw per day as I have been unusually busy this last couple of weeks and I had to drive 150 miles back from collecting the car.

I have sentry mode on FWIW.

I am assuming (you know what that did) I would save around £400-500 a year?

If I have this wrong then great as I need to cancel the smart meter asap!!!

But thats how I am working it out? Anyone confirm my maths?

PS this is before I re set my dehumidifier to run on the EV hours.

[samoht]

I think the above is broadly correct.

8.5 kWh a day charging x 3 miles/kWh efficiency = 9k miles a year, at 4 m/kWh it's 12k miles a year.

Doing those annual mileages in an EV, a cheap rate overnight tariff is worthwhile.

Even if taking 6 kWh a day, 6500-8500 miles a year, that's ~£1 a day cheaper.

The surcharge on the day rate you're paying (are all figures inc VAT?) is small, so the savings are bigger and more robust to varying EV usage estimates.

Honestly I'd get the smart meter and probably go to the EV tariff. Then look back and see how your usage actually splits after a few months of having the Tesla and of shifting what domestic usage you can to the cheap hours. You can always change tariff again in a year - even if you turn out to have made the "wrong" decision it's likely to be a fairly small amount of money in the overall context of car and house running costs. So I wouldn't sweat too much, it's probably an experiment worth doing.

[TheDeuce]

gotoPzero said:

I am a bit confused.

Our current rate is 28.44 which is obvs 24/7.

Our house seems to use about 10kw a day ave.

The EV rate I was looking at is 30.23 in the day and 9p for 4 hrs at night. So costs me c20p a day more on EV for the house.

But on the car I am saving £1.60 per day? (assuming it takes the full 2kw x 4hrs per night)

So I am saving £1.40 per day?

Is that not right?

I had the car 19 days and have charged 160kw.
So thats 8.5kw per day.

Admitidly its currently sat on the drive at 80% soc. So some of that is in the car, so to speak.

I think my average will come back down to about 6kw per day as I have been unusually busy this last couple of weeks and I had to drive 150 miles back from collecting the car.

I have sentry mode on FWIW.

I am assuming (you know what that did) I would save around £400-500 a year?

If I have this wrong then great as I need to cancel the smart meter asap!!!

But thats how I am working it out? Anyone confirm my maths?

PS this is before I re set my dehumidifier to run on the EV hours.

Yes it should be far cheaper - and more so than your basic calcs on the basis that once you have the cheap rate hours in place, you'll inevitably find more household stuff that you can move into the cheap hours.

We're with octopus intelligent, our average unit cost is about 13p now we've moved washing machine and dishwasher etc to cheap hours.

[gotoPzero]

samoht said:

(are all figures inc VAT?)

Yes vat inclusive.

[gotoPzero]

I am not that worried about miles / kw and all that. I am just looking at what kw the car uses per day.

And so far its about 8.5kw a day, but like I said thats including a 150 mile drive I dont normally do.

So all in all I think 6kw a day is probably where I will land.

I was just getting worried as people were saying it wasnt worth going onto EV rates.

[clockworks]

gotoPzero said:

I am not that worried about miles / kw and all that. I am just looking at what kw the car uses per day.

And so far its about 8.5kw a day, but like I said thats including a 150 mile drive I dont normally do.

So all in all I think 6kw a day is probably where I will land.

I was just getting worried as people were saying it wasnt worth going onto EV rates.

To put it into context, before I got my plug-in Hybrid I was on the standard EDF tariff. I was paying £141 a month DD. We had even switched off the immersion heater to try and keep the bills down, just boiling the kettle for hot water in the kitchen.

We are now paying £155 a month on Octopus Go. That's with charging the car, running the immersion overnight, and mostly having the dishwasher and washing machine on overnight.

So, with a bit of juggling, we are getting 350 miles and hot water for £14 a month.

[MrTrilby]

gotoPzero said:

I am not that worried about miles / kw and all that. I am just looking at what kw the car uses per day.

And so far its about 8.5kw a day, but like I said thats including a 150 mile drive I dont normally do.

So all in all I think 6kw a day is probably where I will land.

I was just getting worried as people were saying it wasnt worth going onto EV rates.

For that low a usage it may not be worthwhile to use an EV tariff. It depends a lot on how much power you use during the day, when an EV tariff is relatively expensive. If you’re on Octopus you can use one of many apps - Octopus Compare and Octoscope are suggestions - to compare tariffs and see which is actually best for your usage.

We tend to charge around 15kWh per night, and use about the same again during the day in winter. For us, Octopus Agile works out cheaper than Intelligent Octopus (£128 last month on Agile compared with £190 had we been on Intelligent). Octopus Tracker is also worth a look (would have been £189 a month last month for us)

[gotoPzero]

Just to give the final result we went with Intelligent Octopus in the end. First charge was last night seemed to work ok.
Will see how it goes over the next few months!