EV charging cost calculations
Discussion
Previously had an iPace but charged at work so didnt think about cost.
Mulling over getting another EV (not sure what) and trying to work out rough costs.
The last 4 months I have spent £340 on petrol and have driven give or take 1500 miles.
So, by my maths that £340 will get me 1200kW of juice? (29p per kW)
Assume 2 miles per kW am I right in thinking for the same cost I could go about 2400 miles?
Cheers!
Mulling over getting another EV (not sure what) and trying to work out rough costs.
The last 4 months I have spent £340 on petrol and have driven give or take 1500 miles.
So, by my maths that £340 will get me 1200kW of juice? (29p per kW)
Assume 2 miles per kW am I right in thinking for the same cost I could go about 2400 miles?
Cheers!
2mi/kWh seems pretty pessimistic, unless you plan on getting a full-fat E-Tron. My Model 3 Performance has averaged 3.424mi/kWh this year so far.
Can you not charge at less than 29p/kWh average also?
Around 60% of my charging has been overnight at 7.5p/kWh, I’m lucky as most of the rest has been “free” excess solar generation, which brings my average home charging cost down to below 4p/kWh.
Can you not charge at less than 29p/kWh average also?
Around 60% of my charging has been overnight at 7.5p/kWh, I’m lucky as most of the rest has been “free” excess solar generation, which brings my average home charging cost down to below 4p/kWh.
Maybe. Depends on the tariff. I’m on Intelligent Octopus. They control the charging. You say what % you want and by what time in the morning. You are guaranteed cheap rate 11:30-05:30 (for everything, not just the car). But they can schedule outside then if it makes sense (say lots of wind power earlier driving down the wholesale cost). If that happens you get that at cheap rate too
gotoPzero said:
Ah. Did not know that. So like the old economy 7?
Indeed.We only have 4 hours at cheap rate - enough to dump 28kWh into our Kona, and generally enough to keep us topped up.
We average around 4miles/kWh, so at 9p per kWh, we would pay £2.52 for those 28kWh, which take us around 112miles. I’d simplify that to perhaps say £2.50 for 100miles, or 2.5p per mile…..£25 for 1,000miles, £250 for 10,000miles
So you £340 would buy around 15,000 miles. 10x as far as your previous car….
Happy days!
Of course you may have the occasional long run needing your peak rate price to fill up, or indeed public charging at 2x (or more!) of your home cost.
eta how much went into the Kona!
Edited by mikeiow on Saturday 11th November 23:32
mikeiow said:
Indeed.
We only have 4 hours at cheap rate - enough to dump our Kona, and generally enough to keep us topped up.
We average around 4miles/kWh, so at 9p per kWh, we would pay £2.52 for those 28kWh, which take us around 112miles. I’d simplify that to perhaps say £2.50 for 100miles, or 2.5p per mile…..£25 for 1,000miles, £250 for 10,000miles
So you £340 would buy around 15,000 miles. 10x as far as your previous car….
Happy days!
Of course you may have the occasional long run needing your peak rate price to fill up, or indeed public charging at 2x (or more!) of your home cost.
Great thanks - thats even better than I was thinking. Man maths at its best.... means cheaper electricity = more expensive car We only have 4 hours at cheap rate - enough to dump our Kona, and generally enough to keep us topped up.
We average around 4miles/kWh, so at 9p per kWh, we would pay £2.52 for those 28kWh, which take us around 112miles. I’d simplify that to perhaps say £2.50 for 100miles, or 2.5p per mile…..£25 for 1,000miles, £250 for 10,000miles
So you £340 would buy around 15,000 miles. 10x as far as your previous car….
Happy days!
Of course you may have the occasional long run needing your peak rate price to fill up, or indeed public charging at 2x (or more!) of your home cost.
gotoPzero said:
Previously had an iPace but charged at work so didnt think about cost.
Mulling over getting another EV (not sure what) and trying to work out rough costs.
The last 4 months I have spent £340 on petrol and have driven give or take 1500 miles.
So, by my maths that £340 will get me 1200kW of juice? (29p per kW)
Assume 2 miles per kW am I right in thinking for the same cost I could go about 2400 miles?
Cheers!
Don't forget charging losses. For sake of example I'll use 30p/kWh. So that "buys" you 1133kWh however you will have somewhere between 3% and 20% charging loss depending on how, when and where you charge it. Mulling over getting another EV (not sure what) and trying to work out rough costs.
The last 4 months I have spent £340 on petrol and have driven give or take 1500 miles.
So, by my maths that £340 will get me 1200kW of juice? (29p per kW)
Assume 2 miles per kW am I right in thinking for the same cost I could go about 2400 miles?
Cheers!
Again for sake of example and making the maths easy I'll use 15% which means from that 1133 you've paid for you have roughly 950kWh of actual charge in your battery.
At 2 miles per kWh that's 1900 miles
At 3 miles per kWh that's 2850 miles
At 4 miles per kWh that's 3800 miles
At 5 miles per kWh that's 4750 miles.
Finally just be aware that many tariffs were pulled during the energy crisis so it's all very well and good the people saying "well I pay 7.5p/kWh" but you may not be able to get that kind of deal now!
They are however starting to bring them back but many are "existing customers only" (eg Octopus, Ovo) or require you to move gas as well, you may need to factor in 6 months of more expensive tariffs before getting on the cheap one if the "best" rate for you is "existing customers only".
That said you can probably get about 8p/kWh (12am-5am rate) "immediately" with someone like EDF.
I was existing EDF customer, switched to their GoElectric. Readily available.
8p for 5 hours overnight, 35p daytime. Works for me, probably better out there but was an easy switch.
Also use as many appliances during that 5 hour window, so well over 50% of usage is in the 8p window, to minimise the expensive stuff.
One drawback, the good EDF usage app died, they know it doesn’t work with this tariff. So I downloaded Hugo instead which is Ok.
8p for 5 hours overnight, 35p daytime. Works for me, probably better out there but was an easy switch.
Also use as many appliances during that 5 hour window, so well over 50% of usage is in the 8p window, to minimise the expensive stuff.
One drawback, the good EDF usage app died, they know it doesn’t work with this tariff. So I downloaded Hugo instead which is Ok.
For £340 you can do a lot of miles regardless of EV efficiency, but it clearly depends on a charging arrangement. Public charging can be hideously expensive but I don't need it.
We have a volvo XC40 pure electric, doesn't do anywhere near its claimed range but then nothing does. My wife does 80 miles a day in it where she used my Golf GTD before at a steady 55 mpg. It costs substantially less in propulsion alone even versus that.
Had it 6 months, have never had to charge at a public charger, and according to my zappi log we've done ~2900kwh of charges and have done 9200 miles.
Even if all charging was on Octopus go it would have cost £260 but in our case we have benefitted from solar panels when the stars aligned (eg car at home and British weather allows the sun through). Worth remembering that the day rate is almost 30p per kwh though so if you don't do big miles the crossover to an EV tariff needs thinking about with your daily usage at home as your bill will go up slightly.
Because of the miles she does ours was a no brainer on the company car scheme.
As other threads show some people are kidding themselves with feel good on an EV tariff plus load shifting as your average can still end up higher than other smart tariffs if you don't do the mileage to warrant the charging.
We have a volvo XC40 pure electric, doesn't do anywhere near its claimed range but then nothing does. My wife does 80 miles a day in it where she used my Golf GTD before at a steady 55 mpg. It costs substantially less in propulsion alone even versus that.
Had it 6 months, have never had to charge at a public charger, and according to my zappi log we've done ~2900kwh of charges and have done 9200 miles.
Even if all charging was on Octopus go it would have cost £260 but in our case we have benefitted from solar panels when the stars aligned (eg car at home and British weather allows the sun through). Worth remembering that the day rate is almost 30p per kwh though so if you don't do big miles the crossover to an EV tariff needs thinking about with your daily usage at home as your bill will go up slightly.
Because of the miles she does ours was a no brainer on the company car scheme.
As other threads show some people are kidding themselves with feel good on an EV tariff plus load shifting as your average can still end up higher than other smart tariffs if you don't do the mileage to warrant the charging.
Edited by tvrfan007 on Saturday 11th November 07:55
I switched from EDF to Octopus, then switched to Octopus Go as soon as I could. Took less than 2 weeks.
Now paying 9p between 00:30 and 04:30, 30.25p the rest of the time.
Despite the day rate being 3p higher than my old EDF tariff, switching the immersion heater and dishwasher to running overnight, it saves about 20p a day.
Real cost of topping up my XC40 T5 plug-in hybrid is averaging 3.8p per mile.
Running it on petrol costs 18p a mile, so a decent saving.
Now paying 9p between 00:30 and 04:30, 30.25p the rest of the time.
Despite the day rate being 3p higher than my old EDF tariff, switching the immersion heater and dishwasher to running overnight, it saves about 20p a day.
Real cost of topping up my XC40 T5 plug-in hybrid is averaging 3.8p per mile.
Running it on petrol costs 18p a mile, so a decent saving.
sam.rog said:
Had my Model Y a month and 1500 miles. Cost £30 to fuel.
For your £340 I’ll be able to cover over 16k miles.
Makes sense to switch tariffs for this kind of mileage. For 350 miles a month as per the OP's usage potentially not though, especially heading into the winter where household power usage is at its highest?For your £340 I’ll be able to cover over 16k miles.
Big Nanas said:
Or OVO's 'Charge Anytime' is now only 7p, and you can charge anytime during day or night.
I believe the way it works is that if you charge during what OVO define as "greener" periods you get the difference between your standard tariff and the charge anytime tariff credited to your account at the end of the month. You don't get the 7p rate whenever it suits you to charge. All a bit vague Id suggest?
SWoll said:
Big Nanas said:
Or OVO's 'Charge Anytime' is now only 7p, and you can charge anytime during day or night.
I believe the way it works is that if you charge during what OVO define as "greener" periods you get the difference between your standard tariff and the charge anytime tariff credited to your account at the end of the month. You don't get the 7p rate whenever it suits you to charge. All a bit vague Id suggest?
It is just for car charging though, unlike the other time-limited tariffs which you can use cheap electricity to run washing machines, dishwashers etc. It's worked very well for us.
Having a PHEV with a short range on battery means I often need to charge in the daytime. This, coupled with a low annual mileage means that being on an EV tariiff with its higher daytime rates doesn't make sense. Our daytime use is higher than many due to the house being occupied all the time. At 27p/kWh and petrol at £1.50 per litre the respective costs are very roughly 2:1 in favour of electricity. Assumptions are 35-40mpg and 3.2 m/kWh
SWoll said:
Makes sense to switch tariffs for this kind of mileage. For 350 miles a month as per the OP's usage potentially not though, especially heading into the winter where household power usage is at its highest?
As I said in my earlier post, switching to Octopus Go from the standard EDF tariff saves me 20p a day just on normal household usage - immersion heater (45 mins each night) and dishwasher (twice a week). If I run the washer and dryer at night, that saves another 40 or 50p.I can then charge my car 4 or 5 times a week at 9p per kwh, which saves another £1.70 each time. My car is a plug-in hybrid, so only doing around 4000 miles a year on the battery.
Obviously the potential savings are greater with a fully-electric car and/or a higher mileage, but it definitely works well for me, saving around £30 a month.
For reference, our electricity usage is around 6200kwh per year, excluding the car. Car charging adds another 1800kwh
Fastdruid said:
Finally just be aware that many tariffs were pulled during the energy crisis so it's all very well and good the people saying "well I pay 7.5p/kWh" but you may not be able to get that kind of deal now!
There was an issue during the energy crisis caused by the government support that meant they had to average the cost over the peak and off-peak periods that caused the off-peak rate to rise, but now that the government support has ended that issue has disappeared and the rates are back down to 7.5p.Although actually with the free electricity 'Power-Up' sessions that Octopus is doing in the east of England, I have hardly paid anything at all to fill my car for the last few months.
Fastdruid said:
They are however starting to bring them back but many are "existing customers only" (eg Octopus, Ovo) or require you to move gas as well, you may need to factor in 6 months of more expensive tariffs before getting on the cheap one if the "best" rate for you is "existing customers only".
Sorry but that is nonsense. Octopus will quite happily take you as an electricity customer only and although they put you onto their standard tariff for the transfer then as soon as you have done the onboarding test charge with Intelligent you are transferred to that tariff, so 24 hours on the standard tariff not six months.Gassing Station | EV and Alternative Fuels | Top of Page | What's New | My Stuff