Estimating fuel cost
Discussion
It's ridiculous really.
This is the energy readout from the 15 mile round trip I just did dropping my lad at college. Not driving for range, gave it the beans a few times and a mixture of town and A-Road driving. In a 500bhp, 2 tonne car capable of 0-60 in just over 3 seconds.
50% battery remaining, 154 miles of predicted range, average of 276 Wh/mile. Even at our expensive 12p a kW off peak cost that's 3.3p per mile in fuel. I'd guess a similar ICE car driven on the same trip would cost 20p+?
This is the energy readout from the 15 mile round trip I just did dropping my lad at college. Not driving for range, gave it the beans a few times and a mixture of town and A-Road driving. In a 500bhp, 2 tonne car capable of 0-60 in just over 3 seconds.
50% battery remaining, 154 miles of predicted range, average of 276 Wh/mile. Even at our expensive 12p a kW off peak cost that's 3.3p per mile in fuel. I'd guess a similar ICE car driven on the same trip would cost 20p+?
Max_Torque said:
BTW, i3 owners, the car will always try to AC charge immediately when plugged in, although normally that charge will be terminated after about 15 seconds. This is to:
1) check the EVSE is actually working as soon as it is plugged in
2) Establish the power capability of the EVSE
3) Carry out necessary EVSE and OBC system functional and safety checks (earthing, contactor state etc)
If the Nav is set with a destination and departure time, so the car knows how much energy you require, if you set the scheduled charging for say overnight cheap rate, this can get overidden if the system calculates insufficient time available in that period with the power of charger to which it has just been connected to supply that energy need and hence the car will stay charging.
The car may also stay charging if one of the following cases are true
1) The battery or motor system is too hot - it'll use the mains AC power for a bit to help run the pumps and fans to cool the powertrain down a bit
2) The 12v battery is at a low SoC - AC power will be used via the OBC and DC/DC to charge the 12v battery until it's SoC has reached an acceptable level
Great info, thanks very much. 1) check the EVSE is actually working as soon as it is plugged in
2) Establish the power capability of the EVSE
3) Carry out necessary EVSE and OBC system functional and safety checks (earthing, contactor state etc)
If the Nav is set with a destination and departure time, so the car knows how much energy you require, if you set the scheduled charging for say overnight cheap rate, this can get overidden if the system calculates insufficient time available in that period with the power of charger to which it has just been connected to supply that energy need and hence the car will stay charging.
The car may also stay charging if one of the following cases are true
1) The battery or motor system is too hot - it'll use the mains AC power for a bit to help run the pumps and fans to cool the powertrain down a bit
2) The 12v battery is at a low SoC - AC power will be used via the OBC and DC/DC to charge the 12v battery until it's SoC has reached an acceptable level
Pixelpeep Z4 said:
having done 60,000 miles in an i3 i'd say you'll struggle to see 4.0 miles/kWh if you are doing anything other than 100% town driving,
aim for 3 - we averaged 3.3 over the ownership term (3 years) with 60% motorway 30% town and 10% hooning
Over 12k miles from new, my I3S (120 Ah) has averaged an indicated 4.1 miles/kWh with a 50/50 split between town & open road/motorway driving. I precondition the battery on full charge for the winter journeys (it isn’t garaged either) & mainly run in Eco-pro mode, but sit between 65-70 mph on dual carriageways & otherwise at the speed limit where possible. I don’t drive like a granny, but do enjoy the “one-pedal” driving where possible so perhaps the battery efficiency has improved quite a bit since yours was built?aim for 3 - we averaged 3.3 over the ownership term (3 years) with 60% motorway 30% town and 10% hooning
MrC986 said:
Pixelpeep Z4 said:
having done 60,000 miles in an i3 i'd say you'll struggle to see 4.0 miles/kWh if you are doing anything other than 100% town driving,
aim for 3 - we averaged 3.3 over the ownership term (3 years) with 60% motorway 30% town and 10% hooning
Over 12k miles from new, my I3S (120 Ah) has averaged an indicated 4.1 miles/kWh with a 50/50 split between town & open road/motorway driving. I precondition the battery on full charge for the winter journeys (it isn’t garaged either) & mainly run in Eco-pro mode, but sit between 65-70 mph on dual carriageways & otherwise at the speed limit where possible. I don’t drive like a granny, but do enjoy the “one-pedal” driving where possible so perhaps the battery efficiency has improved quite a bit since yours was built?aim for 3 - we averaged 3.3 over the ownership term (3 years) with 60% motorway 30% town and 10% hooning
Max_Torque said:
MrC986 said:
Pixelpeep Z4 said:
having done 60,000 miles in an i3 i'd say you'll struggle to see 4.0 miles/kWh if you are doing anything other than 100% town driving,
aim for 3 - we averaged 3.3 over the ownership term (3 years) with 60% motorway 30% town and 10% hooning
Over 12k miles from new, my I3S (120 Ah) has averaged an indicated 4.1 miles/kWh with a 50/50 split between town & open road/motorway driving. I precondition the battery on full charge for the winter journeys (it isn’t garaged either) & mainly run in Eco-pro mode, but sit between 65-70 mph on dual carriageways & otherwise at the speed limit where possible. I don’t drive like a granny, but do enjoy the “one-pedal” driving where possible so perhaps the battery efficiency has improved quite a bit since yours was built?aim for 3 - we averaged 3.3 over the ownership term (3 years) with 60% motorway 30% town and 10% hooning
As max has said - around town the i3 was in it's element - what it didn't enjoy was motorways. The e-niro we have now is a stark contrast - that can sit at 90mph with the heater on full in the dead of winter and still return 220 miles from a claimed max of 282.
Under those conditions our old i3 would struggle to do 60 of the claimed 130.
Our 120ah i3 did a 160 mile round trip to Manchester airport in September 2019 (mostly M6), with a week sat in the long stay car park, and got us home without any charging required and 5-10% remaining. That was 2 up with luggage.
Really impressed me as was expecting to have to stop on the way back.
Really impressed me as was expecting to have to stop on the way back.
SWoll said:
Our 120ah i3 did a 160 mile round trip to Manchester airport in September 2019 (mostly M6), with a week sat in the long stay car park, and got us home without any charging required and 5-10% remaining. That was 2 up with luggage.
Really impressed me as was expecting to have to stop on the way back.
That is impressive compared to the previous gen i3 - sounds like they've stepped up their game.Really impressed me as was expecting to have to stop on the way back.
SWoll said:
Discombobulate said:
If you only charge off peak, and if you get 4 miles per kWh.
I have averaged 3.7 in my new 120 Ah i3 over the last 2000 miles and 3 months.
Still v cheap though.
Seems about right for spring especially with the poor weather we've had. We averaged 4 across 12 months and 15k in ours. I have averaged 3.7 in my new 120 Ah i3 over the last 2000 miles and 3 months.
Still v cheap though.
It's the height of Summer so best case, but still pretty good.
LordGrover said:
SWoll said:
Discombobulate said:
If you only charge off peak, and if you get 4 miles per kWh.
I have averaged 3.7 in my new 120 Ah i3 over the last 2000 miles and 3 months.
Still v cheap though.
Seems about right for spring especially with the poor weather we've had. We averaged 4 across 12 months and 15k in ours. I have averaged 3.7 in my new 120 Ah i3 over the last 2000 miles and 3 months.
Still v cheap though.
It's the height of Summer so best case, but still pretty good.
monday-friday daily commute, 40 mile round trip each day - 95% motorway @ around 80mph with the A/C on constantly. It gets charged once a week at home on the 7kw wall charger.
£6 in electric, and our tariff is shockingly expensive (OVO... can't switch until October)
dgswk said:
Shakes head.... if only BMW would continue the i8 and make it full EV
If they did, I'd have another on the drive in the morning, it was a great car, just not quick enough...even if they did the same as before and stuck the 40 motor in, instead of the weedy 3 cylinder, a nice round 500hp would make it a wonderful car.
Discombobulate said:
If you only charge off peak, and if you get 4 miles per kWh.
I have averaged 3.7 in my new 120 Ah i3 over the last 2000 miles and 3 months.
Still v cheap though.
I was going to say that 4 miles per kWh is a little high too. 2018 i3 Rex and had it for a year now. We get an average of around 3.7 also for most of the year, but that does take a tumble during summer though. Currently getting around 3.2 due to aircon. But we don’t get cold winters here so it’s worth considering the hit in cold weather too. I have averaged 3.7 in my new 120 Ah i3 over the last 2000 miles and 3 months.
Still v cheap though.
I don’t hang around in it, and local driving means that it will hit the average number. But with some longer trips recently (before it got hot) I was seeing 4.2 and more but the average drops this down.
It’s still impressive, but not as good as some of the more modern and efficient EV’s out there.
Oh and for reference, during summer we average 35 C (with peaks of 40 a couple of times), and we do use the climate cooling feature pretty heavily. As for cold, it never really freezes, with an average winter temp of around 6 C.
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