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Discussion Starter #1
I’ve had my M3 since 9th November and only just ticked over the 1,000 mark on the odometer (not many miles I know, but living in and around London, I drive around 5-6k miles a year).

Looking at the Lifetime trip computer readings, it says I’ve done an average 304 Wh/mi and consumed 307 kWh after exactly 1,010 miles.

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If I did this all with home charging it would’ve cost me 13p per kWh on my electricity traffic with Bulb energy, making it a total of £39.91. But I actually filled up 196 of those 307 kWh at SuperChargers for free. So actual total fuel cost so far is 111 kWh x 13p = £14.43.

Sure the Tesla SC free charging won’t last for ever (I only have 204 kWh left from my referral bonus). But comparing my home charging cost with the best case scenario on an ICE executive saloon - doing similar mix of local road, dual carriageway and motorway miles - I would get 400 miles max per full tank. Each tank of fuel costing say £60 @ £1.25 per litre.

So 2.5 tanks of fuel to do 1,000 miles. Total petrol cost £150 vs sub £40 for home charging. £110 saving per 1,000 miles is pretty great I think. Plus this was during the cold winter, my efficiency should improve quite a bit in the spring and summer.
 

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EVEZY code d55d6 *** Try my car cost calculator
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(y) Sounds good! Consider switching to Octopus Go to make more savings - link in my sig!
 

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Discussion Starter #3
(y) Sounds good! Consider switching to Octopus Go to make more savings - link in my sig!
Cheers. Yes it’s something I’m thinking about. Need to assess my entire home electricity usage to work out if it’s worth while at this stage. On average we consume 350 kWh per month (100 kWh of those for charger the M3).

Also a bit put off by stories of long delays in getting the Octopus smart meter installed which would potentially negate any cost savings, and the fact I’ll likely need to upgrade my home charger with smart features that would allow for better charge scheduling.
 

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Don't forget you have charging losses as well that you can't see. Those 111kwh are probably closer to 130kwh from your home charger.
 

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Discussion Starter #6
Economy 7 on bulb would half the home charging costs.
Not sure if I could switch to Economy 7. Is that even possible?
 

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Discussion Starter #7
Don't forget you have charging losses as well that you can't see. Those 111kwh are probably closer to 130kwh from your home charger.
Good point. Although I think I was being quite generous with the ICE fuel costs. So feel the cost comparison is still fair.
 

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I downloaded the logs from my smart charging point to work out how much I really spent on home charging. Adding that to Polar and Supercharger costs, I reckon I have saved £690 over the first three months in ~6k miles compared to the car the M3P replaced. In that time, I wasn’t really trying to exploit my EDF EV tariff. I now do that routinely with the scheduled charging features. I also spent much more on public chargers in the first month than I am likely to do in future now that I’m used to how it works.

I don’t know how long your home charging sessions last, but some of mine last over seven hours. That’s why I chose the EDF tariff that provides the off-peak rate from 9 p.m. to 7 a.m. on weekdays and all day on weekends. They use a smart meter to determine your off-peak usage.
 

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If you regularly need to charge for longer than 4 hours, or need/want flexibility to charge more cheaply other than over night, then Octopus Agile is also worth considering, especially if coupled with a smart Ohme charger.
 

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@Bill N I just downloaded the 12-month, half-hourly rates data for Octopus Agile, it doesn’t seem to go below 8p/kWh and often north of 25p. Is that right or am I missing something? Just trying to determine if it would be better for me than EDF which is 8p off-peak and 18.6p peak.

Also, what does the Ohme do?
 

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Also a bit put off by stories of long delays in getting the Octopus smart meter installed which would potentially negate any cost savings, and the fact I’ll likely need to upgrade my home charger with smart features that would allow for better charge scheduling.
I'm in the middle of doing this and after 14 days I sent an email. Not heard anything back so next week I will start to phone instead and keep doing so until I get a date at least for my SMETS 2 upgrade. My current SMETS 1 meter is technically firmware up-gradable but doesn't appear to be an option yet.

Not sure if I could switch to Economy 7. Is that even possible?
I phoned Bulb to opt for this (cost £120.00) myself last year and they said they don't have any meters so don't offer this. They even advised to switch to one of the big six to get one installed and then switch back :)

I'm over 4K miles now having received my SR+ in August. I may have had a couple of months of warmer weather but my consumption average is currently 274 wh/mi. I expect that to rise to say 280ish over the next couple of months. My commute is mostly steady state up to 70 mph so probably more better suited to a lower average plus you may still be over enjoying the instant torque rush. There's a short section of dual carriageway on my commute that's 7 consecutive traffic lights and I'm now staying left behind cars to stop me burning rubber from each set of lights!
 

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Discussion Starter #12
...
I'm over 4K miles now having received my SR+ in August. I may have had a couple of months of warmer weather but my consumption average is currently 274 wh/mi. I expect that to rise to say 280ish over the next couple of months. My commute is mostly steady state up to 70 mph so probably more better suited to a lower average plus yo may still be over enjoying the instant torque rush!
I’m enjoying the power for sure, but my 2 mile school runs in the cold weekday mornings probably aren’t the best for efficiency.
 

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Discussion Starter #13
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I phoned Bulb to opt for this (cost £120.00) myself last year and they said they don't have any meters so don't offer this. They even advised to switch to one of the big six to get one installed and then switch back :)

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Did the quick maths. Bulb’s economy 7 is 15.288p per kWh peak and 7.455p off peak. Their none economy 7 tariff is 13.0095p per kWh.

My monthly usage on average is 350 kWh -
Home: 250 kWh 99% outside economy hours
Car: 100 kWh

Average monthly cost:
350 x 13.0095 = £44.53
Vs
(250 x 15.288) + (100 x 7.455) = £45.68

So looks like there’s no point in me pursuing this currently.
 

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@Bill N I just downloaded the 12-month, half-hourly rates data for Octopus Agile, it doesn’t seem to go below 8p/kWh and often north of 25p. Is that right or am I missing something? Just trying to determine if it would be better for me than EDF which is 8p off-peak and 18.6p peak.
Today's price drops to 5-6p off peak, and that's high compared to what it's been at recently (it went silly, about 1p, a few days ago, but of course won't do that often). 4pm-7pm is quite expensive (peak time, 25p) but the rest is lower. For me that's about 30% cheaper than bulb so long as I stay out of the peak window.
 

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I’ve had my M3 since 9th November and only just ticked over the 1,000 mark on the odometer (not many miles I know, but living in and around London, I drive around 5-6k miles a year).

Looking at the Lifetime trip computer readings, it says I’ve done an average 304 Wh/mi and consumed 307 kWh after exactly 1,010 miles.

If I did this all with home charging it would’ve cost me 13p per kWh on my electricity traffic with Bulb energy, making it a total of £39.91. But I actually filled up 196 of those 307 kWh at SuperChargers for free. So actual total fuel cost so far is 111 kWh x 13p = £14.43.

So 2.5 tanks of fuel to do 1,000 miles. Total petrol cost £150 vs sub £40 for home charging. £110 saving per 1,000 miles is pretty great I think. Plus this was during the cold winter, my efficiency should improve quite a bit in the spring and summer.
I did about 2000 miles in the first 30 days of having my M3 and the Stats app estimated about £160 saved at 13.84p per KwH versus 33.5mpg At approx £1.24 per litre. The savings are phenomenal.
 

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Yes it’s something I’m thinking about. Need to assess my entire home electricity usage to work out if it’s worth while at this stage
I agree Economy 7 won't save you, but with Octopus Go it is highly likely you will save money just from charging car, more if you can move use of dishwasher, washing machine, etc.

Your daytime rate will increase from 13p to no more than 15p and standing charge may also be slightly higher, but you get 4 hours at 5p!
 

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Did the quick maths. Bulb’s economy 7 is 15.288p per kWh peak and 7.455p off peak. Their none economy 7 tariff is 13.0095p per kWh.

My monthly usage on average is 350 kWh -
Home: 250 kWh 99% outside economy hours
Car: 100 kWh

Average monthly cost:
350 x 13.0095 = £44.53
Vs
(250 x 15.288) + (100 x 7.455) = £45.68

So looks like there’s no point in me pursuing this currently.
Look into Octopus Go. The 12.30-4.30am rate is only 5p per kWh and the rest of the day is around 14.5p. You can charge at the overnight rate just using the car's timer rather than having to get a smart charger.
 

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Discussion Starter #20
I agree Economy 7 won't save you, but with Octopus Go it is highly likely you will save money just from charging car, more if you can move use of dishwasher, washing machine, etc.

Your daytime rate will increase from 13p to no more than 15p and standing charge may also be slightly higher, but you get 4 hours at 5p!
Look into Octopus Go. The 12.30-4.30am rate is only 5p per kWh and the rest of the day is around 14.5p. You can charge at the overnight rate just using the car's timer rather than having to get a smart charger.
I would need an Economy 7 meter to switch to Octopus Go, no?

If so, what would the process be to do that? Or would a smart meter installation be enough. I have a smart meter installed by Bulb, but think it is not compatible with Octopus.
 
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