can anyone check my energy calculations please ?

[s7gpt]

ok I estimate around 10,000 miles a year in my new Model Y Tesla long range

assume an average of 250 miles per full charge
£0.28 per kwh to charge only at home
Add 30% for vampire drain etc so £0.36.5 per kwh
therefore 10,000 divided by 250 gives 40 full charge equivalent ( based on 75kw battery )
40 charges of 75kw @ 36.5pence gives £1095.00 a year ?

 

[browellm]

Sounds a little over cautious to me. Can you get Octopus Go? Peak rates are around £0.30, with 4 hours @ £0.075. Intelligent Octopus is even better if you're prepared to deal with the minor inconvenience the app creates.

 

[Dilly]

I can give you my stats which are based upon a few long journeys and a lot of short ones over nearly two years in my 3LR
I’ve done 4754 miles and drawn 2097 kWh.
thats 0.441kWh/mile
pretty horrific but real world miles
I either charge on Octopus Go cheap rate or solar.

 

[s7gpt]

Sounds a little over cautious to me. Can you get Octopus Go? Peak rates are around £0.30, with 4 hours @ £0.075. Intelligent Octopus is even better if you're prepared to deal with the minor inconvenience the app creates.

thanks, I've based the kwh charge on the price increase in April for British Gas SVR - won't Octopus also go up in April too ?

 

[browellm]

thanks, I've based the kwh charge on the price increase in April for British Gas SVR - won't Octopus also go up in April too ?

Not necessarily. The cap only applies to SVR rates. If you took Go now, it would be fixed for 12 months.

 

[dakaix]

thanks, I've based the kwh charge on the price increase in April for British Gas SVR - won't Octopus also go up in April too ?

Their peak rates & standing charge will do, but so far they have retained the off-peak discounted rates for Go, Go Faster etc.

Out of interest, where did your figure of 30% for phantom drain come from? That seems very excessive!

 

[s7gpt]

thanks, I've based the kwh charge on the price increase in April for British Gas SVR - won't Octopus also go up in April too ?

with the new energy costs for 10,000 miles that

I can give you my stats which are based upon a few long journeys and a lot of short ones over nearly two years in my 3LR
I’ve done 4754 miles and drawn 2097 kWh.
thats 0.441kWh/mile
pretty horrific but real world miles
I either charge on Octopus Go cheap rate or solar.

thanks - on those stats at .28p kwh plus 30% for 10k miles gives around £1600 a year - I only use £2k for the same miles in my Land Rover !

 

[s7gpt]

Their peak rates & standing charge will do, but so far they have retained the off-peak discounted rates for Go, Go Faster etc.

Out of interest, where did your figure of 30% for phantom drain come from? That seems very excessive!

I think someone else on here suggested to add 30% to cover drain, air con, cold weather etc - let me know if this is wrong as very new to all this

 

[Ferret]

I believe the miles and drawn figure above covers all charging, so no need to add 30% again.

Also 4k over two years is low so will have a higher percentage covering drain than you will face.

 

[dakaix]

I think someone else on here suggested to add 30% to cover drain, air con, cold weather etc - let me know if this is wrong as very new to all this

Your consumption might be 30% higher in winter - largely thanks to wind & road conditions - but that's not overall for the year! For example my non-heatpump M3 will average 240-260Wh/mi in Summer, but closer to 300Wh/mi in Winter. Those figures include all usage for the car, driving, HVAC etc.

Stationary phantom drain, when plugged in, amounts to about 5-7% per week. Or about half that if the car is left unplugged. Sentry Mode is higher (6kWh/day) - and therefore best only used when out & about.

Ultimately though you'll find the majority of those here will be charging on an off-peak rate at 5-8p/kWh. Charging at peak hours is best avoided - price aside it's generally the dirtiest electricity!

 

[s7gpt]

thanks all - so confusing when I first thought id get 331 miles from the MY it was a much easier decision. Will try and talk to octopus, even at 38pm day rate and 7.5p off peak I recon I would be around £200 better off a year and of course I may do more miles in the first year of ownership enjoying it.
Tomorrow will look at Super charger costs for the longer run but already seen those prices are going up

 

[Dilly]

I believe the miles and drawn figure above covers all charging, so no need to add 30% again.

Also 4k over two years is low so will have a higher percentage covering drain than you will face.

Yes my 2097 kWh covers normal charging and topping up after any drain.
a short 4 mile round trip to the supermarket with the heater on can cost 12 miles of range.
Something like a twenty mile commute would be far more economical
At the end of the day, it comes down to fuel cost.

 

[Yachtsman]

ok I estimate around 10,000 miles a year in my new Model Y Tesla long range

assume an average of 250 miles per full charge
£0.28 per kwh to charge only at home
Add 30% for vampire drain etc so £0.36.5 per kwh
therefore 10,000 divided by 250 gives 40 full charge equivalent ( based on 75kw battery )
40 charges of 75kw @ 36.5pence gives £1095.00 a year ?

These are my stats for the last 12 months covering 11000 miles, approx 9500 miles of short trips & the remainder long journeys exceeding 150 miles. Hope this helps.
Edit: I’m on Octopus go for off peak charging.

 

[kelvin 660]

That works out at 292 kw/mile as a total supplied energy and I'd say that's really good!
I guess you car is reporting something like 230 kw/mile driven.

 

[Yachtsman]

That works out at 292 kw/mile as a total supplied energy and I'd say that's really good!
I guess you car is reporting something like 230 kw/mile driven.

From memory I think it reports 245ish I’ve not looked since v11

 

[SpareHeadOne]

My stats for reference.

I was on an E7 tariff with Bulb and I'm now on their EV tariff; there's a handful of Supercharger sessions in here as well as one or two "others".

For the first seven or eight months in 2021 the car went almost nowhere because of lockdown and was costing about £9/month in vampire drain until I spotted a setting in Teslascope that I hadn't turned on which reduced that to almost nothing. Sentry mode is really bad for that, I lose around 3% while parked at work, at home I don't have it on because the car is garaged.

Ignore the line that says 170 mi/tank, that's because the software doesn't really have proper EV support yet and some of the calculations are wonky.

I'll echo what others are saying, get on a tariff with cheap overnight electricity if you can, that'll make the biggest difference - even E7 should knock a third off your charge costs at home.

 

[Spuzzz]

ok I estimate around 10,000 miles a year in my new Model Y Tesla long range

assume an average of 250 miles per full charge
£0.28 per kwh to charge only at home
Add 30% for vampire drain etc so £0.36.5 per kwh
therefore 10,000 divided by 250 gives 40 full charge equivalent ( based on 75kw battery )
40 charges of 75kw @ 36.5pence gives £1095.00 a year ?

I think you’re kind of double counting phantom drain. You’ve added 30% to your cost, and then also reducing your range to 250. One of the reasons we don’t get the rated range on these cars is phantom drain. I’d take the 30% out of your calc.

 

[Dilly]

with the new energy costs for 10,000 miles that

thanks - on those stats at .28p kwh plus 30% for 10k miles gives around £1600 a year - I only use £2k for the same miles in my Land Rover !

Electricity cost is certainly a big factor. At 5p mine is less than 1/5th the cost of yours. An off peak window is a real must.
as a small sample, I topped up 81 miles at a cost of just over £1. In truth I’d only done 41 actual miles over a week.
My ICE car would never have achieved that mileage for the cost.
even if those costs quadruple, I’m still in pocket

 

[prabhu]

ok I estimate around 10,000 miles a year in my new Model Y Tesla long range

assume an average of 250 miles per full charge
£0.28 per kwh to charge only at home
Add 30% for vampire drain etc so £0.36.5 per kwh
therefore 10,000 divided by 250 gives 40 full charge equivalent ( based on 75kw battery )
40 charges of 75kw @ 36.5pence gives £1095.00 a year ?

Charging whether AC or DC is quite inefficient. So add another 20% in kWh. However, EVs have excellent regen so reduce 30% kWh. For winter months, add 20%. For summer months reduce 5%.

Tldr; Just enjoy your car without worrying about accuracy of a forecast

 

[DoricJim]

I’ve done a little over 1500 miles in my M3LR and put in 530kwh (total which includes charging losses). Calculated around 345 wh/m.