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4p per mile?? On EV tariffs should be less than 2p per mile.
even the “it’s too expensive” line is starting to sound like excuse not a reason
Hm, that sounds a bit out of touch. £15k is a lot of money for a lot of people.
4p per mile?? On EV tariffs should be less than 2p per mile.
Yes. As I've said before, we save £100/mo on fuel commuting, and her work is only 13 miles away. The Ioniq EV might be the most efficient car you can get, but I would suggest waiting until you can afford a 38kWh one as the 28 is pretty small.
And it might be a bad time to buy a cheaper car as the prices do seem to be plummeting.
As importantly, it’s lovely to drive. Then again, a new petrol car would be too
EVs are soo much better to drive than any ICE. It's a revelation, it's how cars should always have been. All that messing about with smelly fuel, noisy machines with thousands of moving parts and gears and clutches and whatnot seems so crude now.
remaining issue is how easily we can transport bikes and tandems. Nominal range is 280 miles but based on our driving we are getting comfortably over 300, though it will be less with bikes on the car.
how will you be carrying them ? Seems roof bars and racks eat up the range, towbar racks much less so.
The thing to realise is that all electricity is equal... A kWh is a kWh.... Like a litre of petrol is a litre of petrol ..regardless of where it's from...
However... The important thing to consider is how FAST it's delivered...
It's the same sparks coming through your 3pin plug hanging out your window...it's just delivered much slower (say 3kW/hr) than a super fancy Tesla supercharger (200+kW/hr)..
Of course, in order to take advantage of cheaper EV tariffs you'll need a specific EV charger... But if you're on an acceptable overall rate, you may be happy simply NOT having an EV charger and just using the 3 pin plug. This is if you can charge enough for your needs overnight...
To charge my car from full from nearly empty would take about 14hours on a 3pin plug hanging out the window....
But if I needed to solely charge at home, I'd just plug in every night (I use about 30% per day commuting)... And keep it topped up.
So unlike an ICE whereby you'd be daft popping to the local shell every eve to top up, you can EASILY do this at home.
I'm not convinced a community NHS worker would cover more than 100miles per day?
Regarding your longer trips... I've no answer to that... I guess you have to accept the PERFECTION of an EV in and around town (and they are soooo good for that) had to have a downside... Longer journeys being that...
DrP
3kW/hr
You mean 3kW
£15k is a lot of money for a lot of people.
It's roughly the combined cost of the last three cars I've bought.
I’m not convinced a community NHS worker would cover more than 100miles per day?
Brainfart on my part, was still thinking about Molgrips advice to fill up at 50%.
We do have a big patch being North and South Kirklees combined with some services we access in Barnsley; not unusual to have the odd 60+ mile day.
We used to be allocated caseloads by geographical area but not any more.
To charge my car from full from nearly empty would take about 14hours on a 3pin plug hanging out the window….
Which is why I'd prefer a dedicated charger so I don't have to leave a window open constantly.
Regarding your longer trips… I’ve no answer to that… I guess you have to accept the PERFECTION of an EV in and around town (and they are soooo good for that) had to have a downside… Longer journeys being that…
I think the answer is to either borrow money for a more expensive car with a better range or wait for them to become cheaper, probably the latter as I really don't like borrowing money and prefer to save for anything I want.
Last question (honestly). When recharging can you keep the heater on so you don't freeze charging in winter?
<p style="text-align: left;">@molgrips ... I guess I do!</p>
I'm much better working out a kid's dose at mg/kg of antibiotic!
I guess it's useful to think (for the novice..which I still am) that a 40kWh battery will take ROUGHLY 10 hours to 'fill' with a 4kW (per hour) charge rate... (I know it won't... Cos the last 15% really slows down... But hey)
DrP
I think DrP means 3000 joules per second hours per hour.
4p per mile?? On EV tariffs should be less than 2p per mile.
Yeah, well that depends on what's available. For most people, probably. For me, I'm on 16p overnight for 7h. If I could get Octopus Go (which I can't) I'd need to install a charger (which would be over £1000) as it's only 4h per night at the 7p rate which isn't enough charging time on the 3 pin plug I'm currently using. It would also possibly bugger up our heating which uses some storage rads.
TBH once you're down to under 4p per mile (I'm probably closer to 3 if I do the sums) there isn't really that much more to save. On 10k local miles that's only 400 quid over the year (multi-day long distance/holidays etc need public chargers anyway). If I install a charger, change tariff (which as I said isn't available to me anyway) I could make back the installation cost in 6 or 7 years, perhaps.
I think DrP means 3000 joules per second hours per hour.
That's terminal velocity , right.....
DrP
how will you be carrying them ? Seems roof bars and racks eat up the range, towbar racks much less so.
well the tandem(s) will be on the roof, there's not much option there plus I can do it by next week hopefully.
Can't get a hatchback rack to fit, halfords claimed to have one but the side straps pull on the plastic light clusters (embedded in the boot lid) which I'm not having. So I'll be trying a towbar. It's a change from a van for sure 🙂 But I used to have a Nissan micra which handled hatchback rack and roof bars with no problem.
How much of a performance hit remains to be seen...mostly I'm cruising rural roads at moderate speeds rather than tanking up the motorway at 75, so hopefully not too bad.
How much of a performance hit remains to be seen…mostly I’m cruising rural roads at moderate speeds rather than tanking up the motorway at 75, so hopefully not too bad.
there was a post somewhere back on this thread from someone with a Tesla 3 - roof bars and a couple of Thule carriers without bikes loaded knocked something like 50 real miles off the approx 350 they were getting I recall, and a couple of bikes on top brought the range down to about 65% of that with no bikes or racks.
I have gone towbar option on the EV I have on order through Tusker, though I already have the rack, and having a couple of ebikes, roof isn't really an option. If it's just me on my own, bike will fit inside with seats down and front wheel off
as above... bike on roof at 70mph EATS the battery (range drops about 1.7 miles for every mile travelled) ...but at 30mph it doesn't really appear to make a huge difference... I mean, clealy it MUST, but seems insignificant..
fiziks innit..
If i was a PROPER captain planet, I'd take the roof bars on/off all the time, but my use of them is so varied and unpredictable, I just leave them on..
DrP
was still thinking about Molgrips advice to fill up at 50%.
I'm not saying always do that, I'm saying it allows you flexibility if you don't want to or can't plan ahead.
I think the answer is to either borrow money for a more expensive car with a better range
Bear in mind the cost savings on fuel might pay for more car. We crashed our old car, so I looked around and as cars were so expensive at the time anything decent was five or six grand. We would have had to borrow the money, so I was able to compare the cost of the loan for a normal car against the lease for an EV. The EV came out cheaper than the loan would have been overall when fuel cost was included.
Of course in October the car's going back and we'll have no asset, but that's leasing for you 🙂
I was just having a peek at Leafs on Autotrader.. Plenty of higher mileage (70k miles) 40kWh Leafs on autotrader around the £10k mark....
DrP
Don't recommend a Leaf, they'll have to worry about ChaDemo vs CCS then!
a 40kWh battery will take ROUGHLY 10 hours to ‘fill’ with a 4kW (per hour) charge rate… (I know it won’t… Cos the last 15% really slows down… But hey)
If you could maintain the charge rate at 4kW, it would take about 10.5hrs to add 40kWh to a battery. Charging is typically about 95% efficient as some energy is lost as heat. As you say the charge rate slows when the battery approaches fully charged, but the recommendation from most EV manufacturers is not to routinely charge to more than 80%, to minimise the loss of battery life. I only charge to more if the trip will need it. I think some types of battery are more tolerant. I suspect that as well as reducing battery life, the charging efficiency reduces below 95% as it approaches fully charged - the charger is effectively working harder to stuff more electrons into a smaller space.
4kW is 4kJ per hour. 4kW per hour is meaningless unless it's describing how the rate of charge is changing.
^^^^
We use language like that, and we wonder why people get freaked out about EVs / units /charge rates etc etc....
😉
DrP
The charge rate of rapid chargers slows down above 80% but it may only slow to the rate of a 3kW charger. So you may get 3kW up to 99% or whatever. It's the max charge rate of the battery hat goes down, not what your charger can supply.
Last question (honestly). When recharging can you keep the heater on so you don’t freeze charging in winter?
Yes, pretty sure you can. You can also have it heat or cool the car just before you get into it so it's defrosted or cooled ready for you to drive.
4kW is 4kJ per hour
Ahem. per second.
But it's also 4kWh per hour which is usually easier maths when wondering how fast your car will charge 🙂
Are there (m)any chargers supplying 4kW? My 3 pin plug does about 3 and most alternatives are at least double (7.4 for standard domestic installation).
Re the question on roofracks above. I found that my efficiency took about a 25% hit on a combination of motorways at 65mph ish and dual carriageways and B roads. That's just from one trip though and it's for my specific car and driving style so don't read too much into that.
Re 7kW charging speed - I don't think that any modern car would slow down towards the end of charge, except for maybe the last % or two. On a rapid charger mine drops from a 200kW peak charge rate at the lower end of the battery to 20kW (ish) in the last little bit - well above 7kW
4kW is 4kJ per hour
Ahem. per second.
Oops! Quite so. I was going to write something about 4kW being 4kWh per hour and had hours in my brain.
I think 4kW was just a number Dr P picked as easy maths for 40kWh. I don't know of any 4kW chargers. My 13A plug in one is 1.4kW, my Zappi installed charger goes up to 7.2kW, but earlier versions only went to 3.6kW. That corresponds to 32A or 16A.
Are you abroad then? 13A here is about 3kW. Which gives a decent chunk of charge in 7h overnight, but not quite a third of my 64kWh battery. I'm considering whether we should get a dedicated charger, I expect the cable out of the window will get a bit tedious in a while.
Are you abroad then? 13A here is about 3kW
No, UK. It plugs into a 13A socket but it's not a 13A charger. The car is a VW, German sockets are 10A, but perhaps the charger is intended to be compatible with multiple countries so just draws the minimum 6A to maintain charging.
Dilemma time. My company car is up for renewal and I have the choice of a Tesla Model Y standard range, or a few models with longer range, such as a Polestar 2 LR or a Q4 40.
I need decent storage space for running my kids up to Nottingham so am edging towards the MY. If there are any Tesla drivers here, is the supercharger network still a big enough plus, to negate the lower range?
I think 4kW was just a number Dr P picked as easy maths for 40kWh
It was jsut for easy maths, yep..
DrP
The 'h' that DrP nonchalantly dropped from his kWh is interestingly* 'a non-SI unit of time accepted for use with the SI' https://metricsystem.net/non-si-units/accepted-for-use-with-si/hour/
*May not be found interesting by all readers.
That raises the question - do physicists talk about their car batteries in terms of MJ?
My car has a battery capacity of 2.2*10^24 electron volts.
EVs are soo much better to drive than any ICE. It’s a revelation, it’s how cars should always have been. All that messing about with smelly fuel, noisy machines with thousands of moving parts and gears and clutches and whatnot seems so crude now.
But don't you keep buying cars that fall apart and/or spend months in a sort of "diagnostics" phase? Are you the best judge of modern ICE cars?
Are you the best judge of modern ICE cars?
Why do you think I like EVs??
It's not that my cars break down, it's more like I am really picky.
That raises the question – do physicists talk about their car batteries in terms of MJ?
I'd hope they so! Interesting choice of units by an engineer here: http://www.withouthotair.com/c2/page_24.shtml. He uses kWh as his unit of energy, and "kilowatt-hour per day (kWh/d)" as his unit of power in that book.
It’s not that my cars break down, it’s more like I am really picky.
But they do break down, all the time.
FWIW, I'm professionally picky about cars.
Why do you think I like EVs??
Because you haven't bought an electrical lemon yet?
I’m considering whether we should get a dedicated charger, I expect the cable out of the window will get a bit tedious in a while.
We had an outside socket and still went with a charger. Few reasons
- we expect to have 2 electric cars eventually so might as well sort out infrastructure up front
- we wanted to take advantage of 4 hour window for very cheap octopus charging - 7kw would give us all the charge we need
- It's a bit tidier/easy to manage and I'm just not a fan or running 3 pin plugs flat out for ages (I know it's fine but..)
- I'm a total data geek and I really wanted to get my hands on all the stats from the OCPP messages / events
- we reckoned it'd add a bit of value to the house (nowhere near the cost) when we come to sell
- charging round here for public chargers is rubbish, most are 7kw
Not a compelling set of reasons, esp not financially but there's something satisfying about just plugging in the cable, hearing it clunk and knowing it'll fire off when the cheap tariff starts and be done in the morning.
The ‘h’ that DrP nonchalantly dropped from his kWh is interestingly
I'm confusing myself, I think..or not..
So the kWh is the BATTERY energy...
the kW is the power delivered by the charger..
So did I drop an 'h' incorrectly??? I dunno..
DrP
Because you haven’t bought an electrical lemon yet?
It's not cars breaking down that's the problem for me. It's a car that works fine but there's a slight bit of vibration or noise coming from the engine and it's making me constantly wonder what it is and if I should fix it. My cars aren't actually lemons.
So the kWh is the BATTERY energy
A watt is a unit of power, which means energy per unit time, in this case Joules (energy) per second. So a lightbulb of higher wattage is brighter. Over a fixed period of time, the higher wattage bulb uses more electrical energy.
Watts and joules mean any kind of energy. So your car's engine produces a certain number of watts of kinetic energy, and your charger can *supply* a maximum number of watts - 7kW in the case of your home charger. The car may not draw all that, because it regulates the current it is drawing.
If watts is energy per unit time, then multiplying watts by time gives you energy. So that means kWh and Joules are both units of the same thing. And indeed, 1 kWh is exactly the same as 3.6 MJ.
My car has a 100kW motor, meaning its maximum output is 100kW provided I'm below 95mph or whatever the top speed is. It has a 38kW battery which could power the motor at max power for 38/100 hours which is 0.38 hours.
I expect the cable out of the window will get a bit tedious in a while.
Fitting an outside socket would be pretty cheap. We have one in the garden for mowing the lawn.
Fitting an outside 'commando' socket would allow you to use a plug-in 7kW charger, which are cheaper. But they are not fixed down and hence more nickable.
I’m confusing myself, I think..or not..
So the kWh is the BATTERY energy…
the kW is the power delivered by the charger..
So did I drop an ‘h’ incorrectly??? I dunno..
DrP
You're there 🙂
kWh is indeed a unit of energy - so 40 kWh is the amount of energy the battery can store.
kW is a unit of power - so if your charger has a 4 kW power output it delivers 4 kWh per hour.
Power = Energy / Time. And you can re-arrange at will to get for example Energy = Power * Time.
The official SI unit of energy is the Joule. But we charge our cars for hours not seconds so instead of kilojoules (or kilowatt-seconds) we use kilowatt-hours so that your simple maths (40 kWh divided by 4 kW = 10 hours) works.
There's a bit of confusion because people often say '40 kilowatt' when describing their car battery instead of '40 kilowatt-hour'. No-one really cares because we know that when you're discussing a charger you're discussing its power, and when discussing a battery you're discussing its energy capacity. If you were an engineer working in the car industry you might want to discuss the power output of the battery (how quickly it can deliver its energy) but then you'd be on top of your units anyway.
Yay... 10 points for Gryffindor...
DrP
Any Ioniq 5 drivers heard when the V3 supercharger update is happening to make it compatible with 5he I5? Last I heard was Q2 2023……..
IMO the supercharger network gives you way more flexibility than an increased range. The speed and ease of use of the chargers means that it's so easy to nip in and top up. I've rarely had to go outside the network (North Yorkshire aside) and it's never let me down once.
Any Ioniq 5 drivers heard when the V3 supercharger update is happening to make it compatible with 5he I5? Last I heard was Q2 2023……..
I think I read that Ford and now Hyundai have announced they will be converting to selling cars with Tesla's charge port connector standard rather than CCS......so that might endanger this development coming to pass potentially?
I think this is relevant to America. Tesla’s over here use CCS.
Yep, whilst the EU all but mandated a common standard in I think 2014, the wonderful freedoms enjoyed by the US manufacturers allowed them to all choose their own standards. Some manufacturers have now decided to adopt the Tesla plug, which of course means they need to pay Tesla loads of money.
Any Ioniq 5 drivers heard when the V3 supercharger update is happening to make it compatible with 5he I5? Last I heard was Q2 2023……..
Not that I've seen. I barely get more than 60kw in the occasional v2 that I've used with my kia EV6 (so the same GMP platform as the i5). Not even tried a v3, but if it's only going to muster up the same, then on a long road trip it's always going to be a last resort option. So many other options available now and the Tesla app seems to direct owners to their chargers so often there's less queuing elsewhere anyway.