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I’ve learned to charge when there are still a couple of alternative chargers within range if the one I hope to use won’t play ball
100% agree with this !
I watch the charge rate
Also agree. Each car model also behaves a bit differently.
Note whilst I said that its best to bounce off empty I don't mean literally empty.. always need options and charge speed isn't always that important, given that a rest stop tends to be a certain duration anyway (even a pee stop is 10 mins, but throw a coffee or some food in and that's 30mins which is enough for most cars to go from 10 to 60%+)
Looks to me like the slowdown starts around 80%, the stopping strategy depends on how many stops and how long. Stirling PnR (for example) had plenty of fast chargers but with a 40 min limit and we only got to 85%. Which was enough to get home but only just and it was a bit stressful. Ideally we'd have stopped a bit later but it was a convenient time (and price).
They're all a bit different - some slow down at 80% (like the ETron), some peak at fast rates, but slow down from earlier on (like the i4).
Not all slowdown is equal though! My Ioniq 5 slows down at 80% - from 220 to 150!! My old mG 5 only ever got up to 75KW
The ionity at Aire Jura literally stopped charging at 80% though - must be a setting at a busy stop.
Not all slowdown is equal
Yep! Changing from an ETron to an i4 I thought that the rapid slowdown of the i4 would be an issue. But it's 200kW peak vs 150kW peak, and given that the i4 is more efficient the "miles added per minute charging" rate of the i4 is actually a LOT faster (I'm seeing 4.1-4.4 m/kw.hr in the i4 during the last couple of months vs the ETrons 2.7-2.9 in similar conditions - about 50% better effiency). Added to that, with the longer range of the i4 any on-the-road charging I do now tends to be a "little top up to get home", I'm rarely charging outside of the fast region. The swap has been a total game changer.
On the range thing, I’m on day 3 of my i4 and was playing with sport mode earlier. I managed to take 10 miles off the range in 3 miles of use ….. it made cool noises though.. 🤪😁
@iainc - don't take any notice of the i4's predicted range. In my experience it's totally useless. It's very pessimistic !
Sport mode shouldn't use more energy in itself - it just sharpens up the throttle and steering. It might however encourage YOU to drive the car in a way that does though haha.
How are you liking the i4 ?
Thanks, loving it so far, scary rapid throttle response and it gets to the legal limit in no time.
not quite worked out all the app stuff yet, and today after fitting and removing towbar bike rack it came back on after restarting still in trailer mode, which I had to put off manually, which was a bit odd, and there was a wee white exclamation mark triangle in bottom right of ev% part of the driver screen, but that went off when I stopped and restarted. Probably user error !
It's a rather clever car. Sometimes a bit too clever for its own good owners.
It is, however "just a nice car", rather than "an electric car" - in a good way. If they piped in engine noises rather than the Hanz Zimmer noises* you could get away with telling people it's an ICE.
*I've turned these off. My 10 yr old kids disagree though, so I've assigned the "whooshy noise" on/off switch to a shortcut to make it easy to keep them happy, but not annoy me the rest of the time.
Haha, yes, indeed ! I have also turned off the ‘iconic sounds’ option !
This may be of interest: UK Government announces new Regulations for the public EV charging network
"In introducing the Regulations, the Government’s aim is to encourage the switch to EVs by ensuring that public EV charging is as simple and hassle-free as possible by seeking to address the widely reported frustrations over accessibility and quality of public EV charge points (“CPs”). The new measures impose obligations on EV charge point operators (“CPOs”) to ensure a better public charging experience for EV drivers."
I was quite shocked recently, looking at the residuals of 2 year old EV's with low miles. Much cheaper than their cheaper ICE equivalents, so much so, I could be tempted in about 18 months when some 'spare' pension pots are accessible.
I do 3,000 miles pa max, and that's mainly to transport bikes to our caravan. I don't use it Mon-Fri, and we've an other car for distance, plus a city car my son/daughter use. A small capacity EV would suit.
I really like the look of the Honda E, but the range is about 100 miles, but that would do us, even for MrsF to commute in it, charging once a week, and using her car for distances. Used, 2 year old Honda E's with low miles are £20k at the moment, almost half their RRP, another 12 months and they will be very cheap.
An EV electricity rate wouldn't help us as our power use is fairly constant, so cheaper overnight for charging will work out more expensive as the day rate is more.
This may be of interest: UK Government announces new Regulations for the public EV charging network
“In introducing the Regulations, the Government’s aim is to encourage the switch to EVs by ensuring that public EV charging is as simple and hassle-free as possible by seeking to address the widely reported frustrations over accessibility and quality of public EV charge points (“CPs”). The new measures impose obligations on EV charge point operators (“CPOs”) to ensure a better public charging experience for EV drivers.”
Does this mean that Tesla will be forced to open up the entire supercharger network I wonder ?
Does this mean that Tesla will be forced to open up the entire supercharger network I wonder ?
Doubt it. Much in the same way that although it would be useful to anyone in the area to crash in your spare bedroom the government can't mandate that you put it on AirBnB.
An EV electricity rate wouldn’t help us as our power use is fairly constant, so cheaper overnight for charging will work out more expensive as the day rate is more.
If use is constantly above a certain level then an EV tariff could work out for you.
I have a google sheet which I used for our calcs. Not difficult to setup if you know how much you use, what tariff you are on, how many miles you drive, what the economy of the car is and what the EV tariff rates are.
Edit - I should probably tart it up so that it could be useful for others and share it on here.
I suspect the arrival of the Volvo EX30 has changed the plan a bit as I understand the 25K car got delayed, sidelined, and the plan changed to maximum model 3, and drop the price of the Model 3 as the manufacture got cheaper.
Re. the mini-e, drive some other cars to compare it to. If you don't need the range, try the Mazda
I really like the look of the Honda E, but the range is about 100 miles, but that would do us, even for MrsF to commute in it, charging once a week, and using her car for distances. Used, 2 year old Honda E’s with low miles are £20k at the moment, almost half their RRP, another 12 months and they will be very cheap.
Can you get a bike in a Honda E though or planing on using a rack? (for various reasons I wont use one).
Too low range for me though. I use the car infrequently but do occasional trips and need to get 200 miles without adding an hour to the journey recharging.
Sadly Honda like many are focusing on SUVs. I'd hoped for a full EV Civic but their only other full EV they're launching is an SUV. The Civic meanwhile now is a self charging hybrid, so it's a petrol car.
Last thing I want is an SUV. Hate them. I'd rather have an estate but that's difficult these days.
Getting to the point where I may give up the car entirely. Public transport is still a faff to bike locations though.
Don’t crucify me but…
We are two days into semi electric ownership and loving it. We replaced our battered aging Kuga diesel with a Sportage HEV 225 (1.6 petrol turbo plus battery) It manages the power distribution itself dependant on load requested of it, but in traffic and if you are light on the throttle it’s full EV mode all the way. I’m sold on the “drive” - the instant torque (spaceship sound mode say the kids) to move a big vehicle about is amazing.
Other than that is such a technology advanced car compared to my just 6yo 320d it’s ridiculous. 250 miles mixed driven and showing 46mpg average.
Crucify you for hybrid instead of full EV? Hell no, gatekeeping constrains adoption and my view is you get what you want and what you feel will work for you. If it doesn't; you've tried it and maybe decide something else next time.
I have a PHEV as I bought it 5 yrs back as there was no equivelant EV at least anywhere near the money it cost me. It was the same price as the one without a battery so a no-brainer. The range is either pathetic if you're driving 50 miles a day, or amazing if you do what we do and drive 10-15 miles 2 or 3 times a day.
Being hybrid has allowed us to get rid of the 2nd car (our schedules and being quite remote mean that public transport/pedal power don't work) and now have an electric moped instead.
Happy days and glad you're enjoying it
Thanks - similar use case, we do 10-20 miles a day on school runs and to leisure centres for the kids sports, all in stop start traffic, so this’ll mostly be in EV mode. Then at the weekends, 100 mile round trips to triathlons, swim galas and bike races with the bikes on the back, so it’s duality works for us.
yes enjoying it. It’s a lovely car.
250 miles mixed driven and showing 46mpg average.
That doesn't look that good? Are you charging it up at home or letting it charge itself?
It's the HEV, not PHEV.
Work colleague has a new CX60 PHEV and is finding is less 'frugal' than his old Skoda Karoq. He might need to adjust some settings to improve it, but I'm hearing more stories of PHEV's not really being any more efficient than their old ICE cars in mixed driving. My PHEV Octavia still doesn't have a build date, now coming up on a year on order.
Quick report from my Alps Roadtrip.
The charging network on French autoroutes is just fantastic. I’ve never had to wait to plug in at a Duper Rapid charger.
Ive used IONITY with my wife’s Volvo RFID card to get 0.31€\kwh
My new favourite is Engie stations which gives great discounts through Electroverse if you are an octopus customer - €0.32/kwh on a 300KW rapid. Plus they generally have 8-10 chargers per station. They show up as “Last Mile Solutions” on the. Electroverse app.
We stopped off at a Chateau near Reims last night to break the journey up to Bruges. Plugged in to a 2 pin wall socket Granny charger. Paid him €15 flat fee for 18 hours of charging (about 40kWh added) not massively cheap but very convenient.
@mert. Not sure who that was directed at but yes, I'm aware it's the HEV.
@stcolin. Quite possibly, I think "mixed driving" is doing some heavy lifting there. If your trips are mostly within the range of the battery I'd expect the equivelant mpg to be about twice that of an ICE. If he's taking long trips then he'll be carrying a heavy ol' empty battery around with him. (YMMV based on cost of electric, car type etc). Clearly a full EV will always win efficiency wise (dear god I hope not to revisit this in winter && apologise for jinxing things!)
Re the above; bearing in mind also it’s not run in…. A 5 mile round trip to Sainsbury’s this morning was 71mpg, so that is about double that of a 1.6l petrol pulling an SUV I guess? Our diesel Kuga showed 31mpg for the same trip
The 250 miles at 44 mpg is actually the quoted mpg, but I did have a play with sports mode, and the battery was pretty depleted after us all playing with the car / settings Friday evening in the garage and needed time to charge.
I was pondering earlier, when noticing the silly amount of torque coming from the 335bhp through the wide rear tyres of my week old i4, what it’ll be like in the winter here in the high parts of south Lanarkshire.
As with many, it’s on a salary sacrifice lease, so no options CrossClimates or similar. It’s the standard tyres, as standard..
Thankfully our other car is FWD petrol with new CrossClimates all round…
I’m hearing more stories of PHEV’s not really being any more efficient than their old ICE cars in mixed driving.
Largely from people with big mouths but small desire to understand their car, I think. People seem to buy them and just drive them around on default everything and not plug them in; thereby draining the battery. At this point the engine runs to both power the car and charge the battery, which is inefficient.
You need to think about what you're doing and where you are going, and where the best place to use your electricity might be. For example, plug in overnight, use EV power to get out of your street then let petrol power you along the motorway until you have to go through a city then you can put it in EV mode. Or just battery draining EV assist in town followed by ICE on the open road etc. I think a lot of people aren't willing to think about their driving to that level of detail.
I was pondering earlier, when noticing the silly amount of torque coming from the 335bhp through the wide rear tyres of my week old i4, what it’ll be like in the winter here in the high parts of south Lanarkshire.
It doesn't go through the tyres unless you press the pedal on the right all the way down. So I'd suggest not pressing it all the way down 🙂 I'm assuming BMW have also applied some sort of traction control or ESP since it was invented a long time ago.
I was pondering earlier, when noticing the silly amount of torque coming from the 335bhp through the wide rear tyres of my week old i4, what it’ll be like in the winter here in the high parts of south Lanarkshire.
as Molgrips said above, traction control is your friend here. Electric motors are massively more controllable than ICE, so the car simply won’t allow the wheel to spin (unless on purpose).
I’ve noticed in my previous ETron and now in the i4 - if you floor it in the wet then there isn’t any wheel spin as such, but there is a slight vague feeling and the car doesn’t accelerate quite as quickly.
I did try flooring the ETron from a standstill in a snow covered carpark, and all it’s 400BHP did was to drive off gently with no drama.
So, I think you’ll be fine from a power delivery point of view. How that translates to not getting stuck though I don’t know. Only 2WD and there is only so much grip you’re going to get from 255 tyres on snow - but a pretty good weight distribution . Probably won’t be as good a a FWD with a heavy lump of an engine right over the wheels.
^^^ interesting, and encouraging ! My last bmw was a 520d estate and it was awful in the snow.
Not sure who that was directed at but yes, I’m aware it’s the HEV.
Molgrips comment about Krytons fuel consumption. 46mpg from a petrol HEV the size of a sportage isn't at all bad. I'd expect it to improve significantly once Kryton works out how to drive it, and stops playing with the settings.
I know my 48v hybrid increased about 6-7mpg as i worked out how to modify my driving behaviours to match the engine set up.
Electric motors are massively more controllable than ICE, so the car simply won’t allow the wheel to spin (unless on purpose).
Yes, when we started with EV, trying to get the "usual" strategies for traction control to work (cut torque, apply brakes etc) was a bloody nightmare. Torque reduction on an electric motor can be done in something like 10ms, 30 times faster than an ICE. Inertia of an EV powertrain is also about a tenth of an ICE powertrain. (Depends on AWD/FWD/RWD etc). So now it's mostly done on motor control. Can also detect slip though the motor far quicker than you can through the ABS.
My last bmw was a 520d estate and it was awful in the snow.
Well, they are both RWD BMWs…
Let us all know how you get on, fingers crossed!
^^ indeed ! I have had 2 Audi Quattro’s in between, both with CrossClimates so I have set my expectations accordingly 🤪
<p>ioniq 5 has a snow drive mode where I guess the tolerance for slip and softening of the throttle to maintain control is increased. I would think bmw had the same no?</p>
I must the the refusal of Sal Sac companies to fit All Season tyres to EVs is crazy. The Eco tyres are rubbish in a bit of rain never mind winter….
Hmmmm. Some mixed experiences from US based owners in the link below.
https://www.reddit.com/r/BMWI4/comments/10y6ikp/lf_honest_winter_review_i4_e40/
I don’t think that there a snow mode as such, but there is “Dynamic Traction Control”, which is a notch back on full traction control, allows a bit of slip from what I read in the manual it’s recommended for driving in slush or snow covered roads etc. sounds similar to the Ioniq one.
I suspect that with full TC on, once a bit of slip is detected it reduces power so you could get to the point where the car just refuses to move. Knocking TC back to dynamic or maybe even off would allow some spin to get moving?
I’m looking forward to winter now !
Even the humble Zoé 50 has traction control, ESP or whatever it is that keeps it gripping remarkably well in snow. My only disappointment last Winter was that he handbrake is now electrical (thus useless) as oposed to mechanical on the older models. The ABS is the most effective I've had on any car in the snow.
Edit: On Michelin Cross Climates, not even full Winters.
Just started looking at some EVs, so far the EV6 and Ionic 5.
One thing I wanted to understand is the protocol for queuing for a charger if occupied? With petrol/diesel there is a clear in/out and you just get in line and wait your turn. From what I’ve seen, the chargers in the services are usually at the front of the car park with nowhere to wait. How does this work in practice especially if there are 3 or 4 people wanting to charge?
There isn’t one. Luckily most EV drivers tend to be considerate, but this is becoming more of an issue. Properly planned sites with queuing spaces would be a good start.
The Ionity at Gretna is great for this with randoms waiting in different places. You just have to remember your place in the queue or more likely for me, carry on to option b.
dantsw13
Full Member
There isn’t one. Luckily most EV drivers tend to be considerate, but this is becoming more of an issue. Properly planned sites with queuing spaces would be a good start.
Sounds like that could get stressful, especially if there is nowhere to park nearby. Would have thought they could implement something on the charger whereby you input your reg and it puts you in a queue and displays the reg up next?
Queueing is generally a bit of a nightmare - works well when everyone is co-operating and being friendly. I suspect that will change as EVs become more popular. There really does need to be some form of queueing system - either a physical queue or a "take a number" type approach. I think the issue right now is that the charger operators likely have to lease space from the overall site operators. If they want space for queuing then they will need to pay for that too, so don't and hence the mess.
It'll change - eventually. I predict an app or some form of numberplate recognition etc.
Out of interest is it typical to have to queue or in most cases is there usually a free charger?
That depends on the location and time of day !
At peak times it's not uncommon to have to queue for 5-10 mins.
Worst case can be quite long (I've had two 30 min+ queues over the last year / 20k miles)
A bit like finding your "favourite" petrol station though you get to learn which ones are quieter and when. Sometimes I'll use a more expensive charger when it's busy if I know it's only a small top up to get home - not worth the hassle of queing to save £1-2.
I've never had a queue in my limited use and very rarely seen a queue in the somewhat longer time I started checking them out when I got interested in EVs. I expect it varies a lot with location and time of your driving. My plan would be to have an alternative and move on to that if it looked difficult at the first option (also if the chargers are not working, which may happen at a quiet time!).
But obviously you want to be charging overnight at home the vast majority of the time, if that's possible.
Queue's become a problem when there is a disparity in pricing. At Gretna, I get 32p per Kwh on the Ionity using the Audi card. I suspect it's the same on the other manufacturers schemes. Whereas the new fast chargers in the main car park are 70 or 80p per Kwh. That can be £25-30 difference for me on a reasonable charge.
@oldtennisshoes
That's exactly my trade-off, albeit at the Cambridge Ionity.
It's 32p for me now (will be 26p once I move to using the BMW card), but can be busy.
There is a BP pulse place in Kettering which has 10 300kW chargers (which can dual-charge hence can service 20 cars at 150kW) and rarely more than a few cars there, so very low chance of a queue. If it's a 10kW charge then it's a no brainer to skip the queue. If it's a 70kW charge then I'm more willing to wait!
Oh - final comment - using the various apps you can look at the status of chargers before heading there. They won't tell you if there is a queue, but you can see if there are free chargers if so how many.
Out of interest is it typical to have to queue or in most cases is there usually a free charger?
Best option is not to run to empty so you can always have a plan B/C/etc
One annoyance I’ve noted with EVs is the trend to fit massive 20”+ alloys. Not only do they give a worse ride, more expensive tyres, less pothole resistance more road noise but crucially for an EV they also hurt the range.
I’d have thought they’d be trying to make them as efficient as possible?
If you want the smaller 19” wheels on the Ionic 5 (which are still massive) you have to get the base spec with cloth seats and less options. The 20” wheels on the better spec cars reduce the range from 315 to 295. I saw an article where someone fitted 18” and got another 50 miles range vs the 20s.
I don’t even think the bigger wheels look better and it seems crazy some cars fit expensive air suspension to mitigate the lack of air in the rubber band tyres. Am I the only one that thinks this is daft?
Strangely the BMW ix50 and 60 models get a better range when fitted with 22's over 21's,
something to do with the inserts between the spokes making a flatter wheel.
I don’t even think the bigger wheels look better and it seems crazy some cars fit expensive air suspension to mitigate the lack of air in the rubber band tyres. Am I the only one that thinks this is daft?
There's a lot more to having the air option than just compensating for the lack of air in the tyres.
Big wheels that fit the arches look a lot nicer IMO
I am on the UK BMW i4 FB group, those on 20 inch wheels seem to be around 30- 50 miles less out of a full charge, so 270 ish compared to around 300 miles on the 18's. i have the standard base model which has the
Meant to be the same on the leaf...
16" gets better range and ride than the 17s...
However....I wish I'd got 18s when I replaced the stock wheels... MOAR PIMP BAYBAH....
DrP
Am I the only one that thinks this is daft?
No, it's widely acknowledged, but bear in mind that traditionally people buying new expensive cars often seem to be the kind of people to be impressed by looks over value and function. Not necessarily the case with the EV market 🙂
You might be able to down spec wheels when ordering the higher spec car. I think this can be done with some manufacturers as I'd enquired in the past.
No, it’s widely acknowledged, but bear in mind that traditionally people buying new expensive cars often seem to be the kind of people to be impressed by looks over value and function. Not necessarily the case with the EV market 🙂
You might be able to down spec wheels when ordering the higher spec car. I think this can be done with some manufacturers as I’d enquired in the past.
I’ll be buying secondhand, EVs are taking a bit of a bath at the moment and there are some great deals - maybe I could swap with someone who wants a worse ride and less range🤣
I'm watching used prices very carefully. Check out Leafs they are plummeting. A few pages back there's a post from me saying I'd seen a load of cheap Leaves at £18k; now Autotrader is awash with £10k ones.
We're they £10k before covid? Is this just a resetting to past prices on all of the automotive industry or just EV?
I'd love to move to full EV but environmentally feel it's better to sweat my current 5yr old car for another 5yrs. By then my son may have learnt how to respect our possessions a little better!
EV used prices are tumbling - I've been looking myself. Various cars, only or 3 years old, low mileage, half list price. Leaf, Honda e, corsa, Zoe etc etc. Far cheaper than ICE
We’re they £10k before covid?
These are two or three year old cars I'm looking at. It seems to be the 2nd gen cars that have lower range which are cheap. That said, a 62kWh Kona has a real world 250 mile range, they are still quite cheap at around £16k for the cheapest.
I’d love to move to full EV but environmentally feel it’s better to sweat my current 5yr old car for another 5yrs.
Well, in our case if we had another EV that would make the diesel last a lot longer. I just drove it to the supermarket 1 mile away! Gah!
(Yeah, you can flame me but we needed a ton of food immediately because we just got back from holiday. Normally it's delivery or I walk there to get smaller amounts.)
Haha, I don't think anyone can blame you for needing to go shopping.
That's the sort of thing I'd be getting in I reckon (a leaf). Budget for size/range it feels good value. If we were doing pre-covid mileage i'd rip their arms off but I just don't go anywhere anymore. Now we're down to one car (a PHEV) we kind of get 90% of the benefit of an EV already so makes it a hard sell to jump completely. Particuarly as it's a beast so my wife isn't going to be happy about going down to a hatchback!
I can see you've got less excuses so just get the cheque book out and jump in! 🙂
As I've said before, my wife currently commutes to a place 13 miles away. Doing it in an EV saves us about £80/mo versus the cost of diesel. The issue for us is that we really should have only one car, but we cannot otherwise tow the caravan. But then, we don't go away that often currently so it's looking like an expensive way to get a holiday.
Anyone got an iX40? I'm currently driving one while my Mercedes is being repaired and I can't seem to get it over 2.7 miles per kilowatt.
Queueing in an ICE car is worthwhile as it's maybe 2 minutes per car, but charging an EV might take 30 minutes, so most people would move on unless they were really low (I usually plan to charge early, so that I can move on). I hadn't thought about the charger owner having to rent the space; many chargers have 2 cables and say "dual charging possible", but only one space. I put my car in the adjacent parent & child space, as the cable was long enough and none of the other p & c spaces were in use. I found a snag with dual charging when the guy using the other cable didn't spot how to switch the display over and disconnected my charge. I found I had to unplug and restart from scratch.
I can’t seem to get it over 2.7 miles per kilowatt.
That's about what Drac was getting from his big Audi, not sure if BMWs are similarly afflicted with low economy.
What kind of driving?
doomanic looking at the specs it seems to have a usable 71 kWh battery and projected range of 220 miles giving an absolutely terrible efficiency of 3.1 miles per kWh - so actual of 2.7 doesn’t sound surprising but no idea how BMW managed to make it so inefficient.
I usually plan to charge early, so that I can move on
Yeah. I did a trip that needed about 110% of charge, so I needed to add a bit of charge at some point, but it didn't really matter where I added it other than it took slightly less time if I ran the battery lower.
doomanic looking at the specs it seems to have a usable 71 kWh battery and projected range of 220 miles giving an absolutely terrible efficiency of 3.1 miles per kWh – so actual of 2.7 doesn’t sound surprising but no idea how BMW managed to make it so inefficient.
It's the size of a house and weighs more than Nadine's liquor cabinet. It's also pretty rapid if you hoof it with 326hp.
What kind of driving?
Mixed, mostly town driving in moderate to no traffic but a couple of trips that included NSL dual carriageways. I've been driving it what I consider to be an economical manner for the most part but I took a friend out for a spin today so obviously had to hoof it a couple of times (I'm not including today's driving in my considerations).
A £70K+ car is well out of my price range (in fact there isn't a new EV I can afford currently, I tried to buy an MG 4 on the work salary sacrifice but I don't earn enough... 😢) but these economy figures mean my annual Golfy trip would be cheaper in my Merc!
It’s the size of a house and weighs more than Nadine’s liquor cabinet
It also looks like it was designed by me, when I was 5
I’ve been driving it what I consider to be an economical manner for the most part
What constitutes economical driving in an EV is not the same as an ICE. In an ICE if you boot it, lots of your burning fuel comes flying out of the exhaust so your efficiency drops. In an EV however, in my experience booting it makes very little difference. The main factor seems to be the actual speed you're driving at. In an ICE town driving is the worst because you're in lower gears and you're accelerating all the time, but constant A road driving is better despite having 4x the air resistance to deal with. However n an EV town driving is the most efficient, despite the accelerating. And you recover some of that energy (but not all).
but these economy figures mean my annual Golfy trip would be cheaper in my Merc!
Yeah, even with our super efficient Ioniq and no public charging subscription, charging away from home was about the same cost as my somewhat more frugal Merc. However, with home charging it was a tenth the cost.
I don’t know if it’s a BMW thing , and I’ve mentioned it before, but my iX3 is far more efficient on a 60-70mph run than it is around town
Synchronous AC electric motors do have an efficiency curve, so at very low speeds they do get worse. And the energy cost of running the inverter, the electronics and the HVAC are fixed per minute not per mile, so efficiency in heavy crawling traffic was worse for us but in the worst jams it only went down to about the same as a motorway trip on a cold day. Maybe there is a BMW difference I dunno.
Motor efficiency vs speed and vs load is a thing, but it’s a fairly small factor.
The three things that dominate the game efficiency vs speed curve for both ICE are the “per time” losses - energy to heat or cool the cabin and in an ICE just to keep the engine running, and the frictional and aero losses and efficiency vs load curve of the power source.
ICEs are quite (very) poor efficiency at low loads. There is a minimum level of energy expenditure which is mostly lost to heat at low loads. EVs are fairly flat vs loadZ
Add to the above the fact that EVs (and hybrids) can recoup braking energy* and the peak efficiency for an EV is pretty low - 20mph ish. For an ICE it’s quite a bit higher - 50 ish.
On country road type driving my i4 recoups around 25% of total energy spend according to the trip computer. Obviously that changes with terrain and type of road. Flat motorways would be close to zero. Hilly terrain or city driving is probably higher.
Just talking efficiency... what should I/we expect re. charging efficiency?
We bought a 2nd hand eNiro a few weeks ago and I'm just looking at what it's costing to charge on public charge points recently.
I understand the eNiro has a 64kWh usable battery.
Last weekend I charged from (I think) around 16% to 80% so ~ 41kWh needed to fill the battery. The CPS history shows 47.4kWh drawn in 82 minutes, 87% charge efficiency.
Just now (going on a long journey tonight) I've charged it to 99%. I think it was sitting at 77% when I plugged it in so 22% or ~14kWh. CPS shows 19.7kWh drawn in 94 minutes, 71% efficiency.
I'm not sure on these numbers, I'll pay more attention next time. But if these are anywhere near correct this seems pretty bad. From reading I did before buying I was expecting 90%+ charging efficiency.
It seems like current charge level is having a huge effect on charging efficiency (really best not to charge > 80% if at all possible?). How does charging rate affect efficiency?
While I've found lots of resources for different cars and driving efficiency there seems to be a complete dearth of data on charging efficiency. It seems from these numbers that charging efficiency could be more relevant than driving efficiency (or at least may have a significant impact on overall efficiency).
Just a quick interlude back to the hybrid....
It seems to be wearing in/we are getting accustomed. Mrs K did a 70 mile round trip with her and the two kids, and 2 bikes on a Thule tow bar rack last night. The way out was 3 miles in/out N London, 10 miles dual carriageway of which the way out was congested for the first third, and the rest B roads through Essex. The return journey was 5 miles B road to the M11, 27 miles M11/M23 and 3 miles back into N London.
The result - 50MPG on the nose. She is ambivalent to car stuff, so in her words she " just drove it". So no skewed hyper-miling 😀
@zntrx I have a feeling that charging efficiency is affected by how full the battery is with lower efficiency at the top end.
https://www.caranddriver.com/features/a36062942/evs-explained-charging-losses/
as the battery reaches its maximum capacity, heat can increase, reducing the efficiency of the charge.
We've had our iX1 for a few weeks now. It is very nice.
I have a feeling that charging efficiency is affected by how full the battery is with lower efficiency at the top end.
I think that's true of all lithium ion batteries.
@ZNTRX Interesting - I took a quick look at a few recent charging sessions on my i4. A bit of a pain to drag out data from the apps so I just did a few.
7kW Charger
22-45% charge
Charger (podpoint) showed 18.6kW.hr
Car (BMW i4 app) showed 18.8kW.hr
% differences * battery size = 18.56
Charge efficiency = 98.7-99.8%
7kW Charger
45-92% charge
Charger (podpoint) showed 40.9kW.hr
Car (BMW i4 app) showed 40kW.hr
% differences * battery size = 34.93
Efficiency = 92.7-94.8
Fast charger
6-90% charge
Charger (IONITY) showed 72.5kW.hr
Car (BMW i4 app) showed 72kW.hr
% differences * battery size = 67.79
Efficiency = 93.5-93.8
It looks like the BMW app is either charge taken rather than delivered to the battery.
Charging efficiency looks overall very good. >93% in all cases.
7kW charger at up to 45% was close to 100%, dropping to 93-95 when charged to full.
The fast charger was similar - 94% efficient.
I'd imagine that fast charging is less efficient, due to heat generation which has got to go somewhere - when fast charging I think that the battery back is being actively cooled at higher SOC, so that's energy lost.
@zntrx - those numbers don't look so great. For your charge to 99% indicated an average loss of 4.4kW. That might align with a cooler running on full to cool the battery pack down maybe? Could be just inaccurate input data. Maybe try checking a few sessions with a few different chargers etc to be sure.
Oh yeah - the power to cool or heat the battery to optimum temps comes from the charger which charges you for it. I have read about that.
Yep. Given that all power in an EV ultimately comes from the charger then yes, this is true.
Same applies to power used to pre-heat the car and battery before setting off if you do that. Even if not plugged in it comes from the battery which is then later replenished by charging.