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I think it’s fairly clear that heat pumps don’t make sense financially. As in, you won’t save enough in charging to pay for them.
For me it's range reliability. I don't want to lose 1/3 range in cold weather, or have my range indicator plummet just because it's a cold morning. UK winter barely has an impact on my car - about 10% - and I appreciate that.
shame about canoo, they looked promising as both a recreational van and commercial. ground up design with some useful features rather than shoving a load of batteries in the floor of a 20 y/o ice van platform.
didnt see much over here but think they had some potentially lucrative US government contracts ranging from mail to military... so is it possible Musk has managed to cancel those?
Can you folks help me get my head around charging schedules please. We have an iX3, the BMW app (which seems pretty good for scheduling charging), a Zappi, and Octopus intelligent tariff that sees the car plugged in in their app
I want to charge on the low tariff overnight, but I have seemingly no ability to influence the charging timings. Not sure where in the chain the problem is, but something is changing the charge timings in the BMW app and it will stop charging at 3 in the morning leaving us half full. And sometimes it won't charge cos the app says our next departure is next Tuesday at 5.30AM, when we want it full tomorrow morning. Driving me a bit crazy.
What bit of the chain do i need to dump to be back in charge? Do i dump the Octopus app as that has one setting 23.30 - 07.00 and no ability to tweak. Do i need to do something on the Zappi? I don't want to stop using the BMW app as that one seems to give me the most flexibility.
TIA
For me it’s range reliability
Yep, same for me, it's not about cost, but about not losing as much range in winter, as it happens our car has a heat pump as standard.
We also seem to lose about 10% range in winter compared to summer most of the time, although if temperature starts to go below zero then range does drop by more. Presumably as the temp drops the heat pump becomes less effective and the car starts to rely on the ptc heaters as well, or maybe even instead.
Anyone know the typical temperature when cars swap from using a heat pump to using ptc? Probably a question for mert......
For me it’s range reliability. I don’t want to lose 1/3 range in cold weather, or have my range indicator plummet just because it’s a cold morning. UK winter barely has an impact on my car – about 10% – and I appreciate that.
Yes but they only start to have benefits on longer runs and even then, it's marginal. Wisely tested this on an i3:
What bit of the chain do i need to dump to be back in charge? Do i dump the Octopus app as that has one setting 23.30 – 07.00 and no ability to tweak. Do i need to do something on the Zappi?
Probably not much help, but in a Car-Ohme charger-Octopus setup the advice is to totally ignore car app and Octopus app and do it all via the Ohme app. If the Zappi can talk directly to Octopus, then I assume the same advice would hold.
Yes but they only start to have benefits on longer runs
Longer runs are when the range matters, who cares if the range is only 100 miles or 50% of summer, when it's comprised of short trips because it's most likely you'll be back at home that night and can just recharge again.
Can you folks help me get my head around charging schedules please. We have an iX3, the BMW app (which seems pretty good for scheduling charging), a Zappi, and Octopus intelligent tariff that sees the car plugged in in their app
I only have the basic Octopus (cheap 0030-0530) but as the installer said to me, you can only have one device controlling the charging. So my car is on 'dumb' mode - plug it in and as long as there are electrons being pushed into the wire it'll accept them, up until it's full. I just set the car to specify what full is - so usually 80% and only 90 or 100% occasionally when a need dictates (sl annoying, it keeps defaulting back to 50% as standard so I have to remember the set 80% each time. IDK why, Hyundai Bluelink if anyone has ideas)
So the charger (via an App, QUBEV) decides when to charge, which I've set to 0030 start and 5 hours duration, to match the Octopus cheap rate window.
At 0030, IF the car's plugged in and IF there's space for electrons, it starts sending them, until the 5 hours is up or it reaches 'full', whatever that is.
Sometimes I set it to run longer to top up more (but then pay the std rate instead) or I can put the charger on manual mode where as long as there's a car plugged in with space, it'll just send electrons.
For you - seems like you need to drop the BMW app down to dumb mode, and then let Intelligent Octopus decide when your Zappi can send electricity, based on when they've got spare rather than me deciding a fixed time. IDK exactly what you set, I think it's how much charge you want by when....but not sure. It sounds to me your problem may be that BMW and Octopus are fighting with conflicting demands?
Longer runs are when the range matters, who cares if the range is only 100 miles or 50% of summer, when it’s comprised of short trips because it’s most likely you’ll be back at home that night and can just recharge again.
Sure, but when in 40 miles of driving, you only save 0.7% efficiency, that means that even with a 300 mile drive, you're going to at most save 6%. That 6% is ~4kwh, which is what 30-300p. On the journeys where it matters, it's going to take you a bloody long time to recoup the £500-£1500 delta.
The simple fact is that the drivetrain (not the cabin heat) is the major energy consumer and unless the drivetrain heat is used in the heating system circuit (a la some Teslas), the benefits of a heatpump will be minimal and certainly not economical.
Presumably as the temp drops the heat pump becomes less effective and the car starts to rely on the ptc heaters as well, or maybe even instead.
Well they might still be more effective than PTC. The domestic heat pump we're having installed still has a COP of 2 at its minimum temperature which is something like -30C. That means it's 200% efficient, or twice as efficient as a resistive heater. I expect they use both at lower temperatures just to get more heat in full stop.
On the journeys where it matters, it’s going to take you a bloody long time to recoup the £500-£1500 delta.
For me, when buying a cheaper car it's about the extra range. That 4kWh for me is a sizeable fraction of my available battery.
Thanks theotherjonv - sounds like i might have to do that. have emailed Octopus to hear what they have to say - using the forum hoping someone had had the exact same issues. Will post back when i hear from them
For me, when buying a cheaper car it’s about the extra range. That 4kWh for me is a sizeable fraction of my available battery.
You’ve completely misunderstood. That 4kWh was calculated at % of the energy required to do 300mi and assuming 3.5mi/kWh. If you buy a smaller cheaper EV with a smaller battery, you’re not getting 4kWh saving you’re getting under 5% at the very best (likely 3%)of whatever your range/battery is.
Given the 90mpg winds currently blasting my house today I’m seriously wondering if the foresight to get a car with V2L might have been a fortuitous choice. Power has flickered off a number of times today.
Fully charged the car and looked out the IP65 rated extension lead in preparation to becoming a beacon of light in the coming darkness.
Ordered a polestar 2 long range dual motor....
Now working out best tarrifs etv
If you buy a smaller cheaper EV with a smaller battery, you’re not getting 4kWh saving
Eh? The amount of thermal energy needed to heat a car at a given outside temperature is fixed regardless of how big the battery or car is. So if it takes 1kW to heat the car with PTC and 500W to heat it with a heat pump, I'm saving 0.5kW regardless. And if my battery is smaller that's a bigger portion of the range. Driving 2 hours with that PTC in my example would use 2kWh vs 1kWh with the heat pump - with the saved 1kWh I could drive a further 5 miles beyond the 2hrs. With a larger car I might only be able to drive a further 3.5 miles. Those numbers are small for sure, it's based on what I see with typical UK cool weather.
got a 2nd hand e niro 71 plate 4+ mode; last thursday (previously had a Zoe so have a sync ev charger at home already ) Charged last night for a couple of hours and only put in 10% of charge.
Plugged in today and will only charge at 3.6 to 3.7Kwh on the type 2 at home, phoned sync EV they checked the charger and its pulling 32a so should be 7Kwh. CAble rated to 32a and is a kia cable checked cable and connectors no damage or residue corrosion.
Went to a friends house they have a ev6 and a tethered type 2 charger, plugged in only charging at 3.7kWh, they checked their data and EV6 has charged at 7kWh last night.
All the settings are set in the car that i can access to charger at fastest speed.
Any thoughts suggestions something obvious i may have misssed?
Plunge taken! Just pressed go on company car through the portal. ID7 Tourer GTX with heat pump, folding tow bar, panoramic roof.
This will take us to a 2 electric car family. Coming soon, the road trip range anxiety learning curve ?
susepicFull Member
Thanks theotherjonv – sounds like i might have to do that. have emailed Octopus to hear what they have to say – using the forum hoping someone had had the exact same issues. Will post back when i hear from them
My charging has been spot on with OIG, Hypervolt and an E-tron.
First I cleared all the charging schedules from car, so that the car only controls the max charge limit.
The Octopus App does all of the controlling, but it has to take over / integrate the Hypervolt during the Octopus app set up.
Will try and share a screenshot.
All the settings are set in the car that i can access to charger at fastest speed.
Any thoughts suggestions something obvious i may have misssed?
not sure about Kia but my Born has a ‘slow charge’ option in the apps charging settings (maybe available in the car too but can’t check right now).
All the settings are set in the car that i can access to charger at fastest speed.
How full is your battery? It'll taper the input if it's nearly full or a cold battery?
I once charged my Corsa e at a paid account charger and it drew less than 2kwh. Should of really pulled 6? Maybe there is a reduction from the network when the demand is high or the house is pulling a big load?
Just had my most inefficient drive in the eNiro. In summertime on local trips I often see getting on for 5 miles per kWh. On the motorway at 60mph I generally get around 4 miles per kWh. I work on getting around 200 miles on 80% of the battery (on a trek charging to 100% and staying above 20%).
Drove Aberdeen to Glasgow today just as the storm had subsided. Averaged 2.5 miles per kWh. Set off with 100% battery and had to stop enroute and pay 89p per kWh on a shell charger that wouldnt do more than 40kWh charge rate!
I couldn't make the 160 miles (average speed 50mph), wouldn't have made it on the full battery discharge - ended up with less charge than was added on the pit stop.
The amount of thermal energy needed to heat a car at a given outside temperature is fixed regardless of how big the battery or car is. So if it takes 1kW to heat the car with PTC and 500W to heat it with a heat pump, I’m saving 0.5kW regardless. And if my battery is smaller that’s a bigger portion of the range.
Ah, so maybe that is why heat pumps seem to be less common on cars with larger batteries. If you have 80kwh to play with and your range is varying by 20% based on weather and how you drive anyway, maybe the extra saving from a heat pump starts to look irrelevant.
The amount of thermal energy needed to heat a car at a given outside temperature is fixed regardless of how big the battery or car is.
I don't follow the reasoning here. As I understand it, to keep the car warm in cold weather, you need to heat the mass of the car because the hot air that the heater puts out is cooled by contact with the windows, dash, seats, etc. A larger car will take more energy to heat than a smaller one. Once the car is warmed up, a larger car will dissipate more heat than a smaller one because it has a greater surface area. If the battery needs to be heated in cold weather, then a larger battery will take more energy to reach optimum temperature. If I've misunderstood, I'm happy to be corrected.
A larger car will take more energy to heat than a smaller one.
Yes, of course, but I was making assumptions. The question was about battery size not car size. Of course, if your larger car requires more heating then the absolute amount of energy saved with a heat pump is more - compare say, a 64kWh Kona with a 58kWh Ioniq 5 - the heat pump would have a greater impact on the Ioniq 5.
Regarding battery heating - it is my understanding that they don't get heated in normal driving unless it's super cold like -15 or lower. The optimum driving temperature is lower than the optimum charging temperature however, so the heating feature is mainly used 20-30 mins before a charge stop. I the Leaf with its crude battery temp gauge just driving at motorway speeds warmed it up a lot, of course a bigger battery would warm up less for a similar amount of power consumption when driving.
Every review of that Renault 5 has raced about it. As a car, not just an EV.
To my mind it's exactly the sort of car a lot or people should be aspiring to. Still not cheap but as said in that review taking inflation into account it's not far off of a £10k in the early naughties.
Just had my most inefficient drive in the eNiro. In summertime on local trips I often see getting on for 5 miles per kWh. On the motorway at 60mph I generally get around 4 miles per kWh. I work on getting around 200 miles on 80% of the battery (on a trek charging to 100% and staying above 20%).
Drove Aberdeen to Glasgow today just as the storm had subsided. Averaged 2.5 miles per kWh. Set off with 100% battery and had to stop enroute and pay 89p per kWh on a shell charger that wouldnt do more than 40kWh charge rate!
Although storm had subsided are you sure that you weren't still into a major headwind. That sounds a bit like like my trip to the MiL - Guildford to Yeovil and back on NYD.
On the way we averaged 2.9 on the M3 / A303 with 4 adults on board, into a headwind.
On the way back 4.2, with no discernible difference in the driving style or speed.
Although storm had subsided are you sure that you weren’t still into a major headwind. That sounds a bit like like my trip to the MiL – Guildford to Yeovil and back on NYD.
Definitely it was still very windy. Undoubtedly this was the cause of the drop in efficiency. My surprise was the magnitude of the drop off. Logically, I suppose, it makes sense but still it was something I was not expecting.
On the way we averaged 2.9 on the M3 / A303 with 4 adults on board, into a headwind.
On the way back 4.2, with no discernible difference in the driving style or speed.
I get this kind of thing on the stretch of the M6 between birmingham and manchester (I do this journey once a month or so) - every time going south on the m6 is 15% less efficient than the same journey going north - 2.3 mpkwh going south, 2.7mpkwh going north . similar driving style,speed etc. maybe southbound is uphill?
convert
Every review of that Renault 5 has raced about it. As a car, not just an EV.
To my mind it’s exactly the sort of car a lot or people should be aspiring to. Still not cheap but as said in that review taking inflation into account it’s not far off of a £10k in the early naughties.
Absolutely, it looks like a superb car for the price. I just hope they offer the lighter coloured interior in the UK (like the concept car had).
Every review of that Renault 5 has raced about it. As a car, not just an EV.
To my mind it’s exactly the sort of car a lot or people should be aspiring to. Still not cheap but as said in that review taking inflation into account it’s not far off of a £10k in the early naughties.
The R5 looks great, and I'd have one in a heartbeat if money was no object. In Harry's video he makes the case that it's the perfect second car for people (if they can home charge) - which I totally agree with, and is my usage scenario for my E208. Where I am slightly confused is why the R5 is being seen as exemplar here, but the E208 is pretty much like for like on spec, and a nice 3yr old one can be picked up for £10k. Not quite as stylish, but no dog, very similar spec (including the keyless entry that seemed to impress Harry so much!?) for £10k purchase price + 2p per mile 'fuel' costs - surely that's a better example of 'everyman' second car, than a £33k R5? Or is it really that if you can't get something on a lease then it might as well not exist?
surely that’s a better example of ‘everyman’ second car, than a £33k R5? Or is it really that if you can’t get something on a lease then it might as well not exist?
Actually the R5 is £23K starting price and a bit more for the bigger battery or the posher trim levels .Heat pump standard equipment on every car. A quick google says the E208 is £28-33K new.
But you are right - 2nd hand as ever wins out. Arguably more so with EVs and the depreciation in the first few years of ownership seems so high in comparison to an ICE. I suspect the scepticism will go and that'll change. But a 2 year old R5 (in 2 years time) - could be lovely. An E208 still looks good now though.
When the iD2 comes out there'll be a fight for cheap EVs and soon we'll have plenty of cheap seconds cars to choose from.
Actually the R5 is £23K starting price
Whoops, typo - yes, I meant £23k not £33k!
The depreciation thing always confuses me - yes they drop off a cliff from new - but you can use that to your advantage by letting some other muppet take that hit.
but you can use that to your advantage by letting some other muppet take that hit.
That muppet is in fact the government - they are funnelling cash to the manufacturers by cutting BIK on company car leases; the manufacturers then invest this cash in R&D and production because they are still fighting over their share of the new market; then economies of scale mean that EVs become cheaper for everyone. The govt is effectively subsidising low emissions technology and this is fine by me. If you buy your own new EV you're a muppet, but only slightly more so than if you buy your own new ICE.
When the iD2 comes out there’ll be a fight for cheap EVs and soon we’ll have plenty of cheap seconds cars to choose from.
Hyundai have also just brought out the inster for about £23k.
Hyundai have also just brought out the inster for about £23k.
Compared to the Renault, it looks very cheap though.
just looked on octopus and bigger battery R5 is available for higher rate taxpayer about £370 all in on a 10k/yr lease.
Saw a Dacia Spring on the road today... and it looked, erm, like a normal car...!
Not futuristic, nothing too fancy..jsut a bog standard Dacia style, with a 'leccy motor in it.. I think this is the way the world should go.
I mean, super facny, uber powerful EVs are great and all, but really it's just a car...!
DrP
We were considering a new ID4, against some other hybrids. But, looking into it more, found it was going to be awkward to get a home charger.
We're in a row of 6 cottages perpendicular to the road, in a conservation area, so would need to go through planning, and our electric supply is looped through the other cottages, so will need unlooped, presumably by digging up the shared driveway. When this was done for our fibre, it took months.
so for now, we're going hybrid and will see what the position is in 3 years. or at least start to look at putting infrastructure in a bit earlier..