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One more question, on the spec it says that from zero to 80% on a fast charge it only takes 50min. Does the last 20% charge take longer? Why do they measure it to 80% only? Also, how can I distinguish between fast charging and normal charging. I am thinking that if my work stations are fast charging then I can probably get a full boost within the 4 hours allowance.
This is referring to DC fast charging. The big lumpy chargers that you find in various places, not the smaller AC chargers you probably have at work. The charge rate slows down after about 80% to protect the battery. That's normally the time to clear off from a fast charger. This shows the charging curve on both 50kWh and 175kWh chargers - note the peak is around 77kWh so there's no "point" ever going to a charger rated higher than 100kWh (not that there are many!)


I did 80 miles today, mostly motorway/DC. Used about 30% of battery. I would be comfortable to say about 240 miles in todays moderate conditions.

I'm on Octopus Agile, so it's hard to say exactly as the price fluctuates every half hour. Tonight I reckon I'll be back up to 80% for about £1! The battery is 64kW but you'll never likely be charging from empty - maybe from 20% to 80%; about 40kWh. So if you're paying 14p for a kW that's £5.60. That's why Go is soooo good for EV drivers!

Shameless link to Octopus energy if I've whetted your appetite - sign up and you get £50 and I get £50 (y)

 

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This is referring to DC fast charging. The big lumpy chargers that you find in various places, not the smaller AC chargers you probably have at work. The charge rate slows down after about 80% to protect the battery. That's normally the time to clear off from a fast charger. This shows the charging curve on both 50kWh and 175kWh chargers - note the peak is around 77kWh so there's no "point" ever going to a charger rated higher than 100kWh (not that there are many!)


I did 80 miles today, mostly motorway/DC. Used about 30% of battery. I would be comfortable to say about 240 miles in todays moderate conditions.

I'm on Octopus Agile, so it's hard to say exactly as the price fluctuates every half hour. Tonight I reckon I'll be back up to 80% for about £1! The battery is 64kW but you'll never likely be charging from empty - maybe from 20% to 80%; about 40kWh. So if you're paying 14p for a kW that's £5.60. That's why Go is soooo good for EV drivers!

Shameless link to Octopus energy if I've whetted your appetite - sign up and you get £50 and I get £50 (y)

Thank you very much. That is very useful. The Octopus energy sounds like a killer. I am assuming I need to switch my whole house energy provider. I am with British Gas at the moment, will find out their rates then give them a call to see the costs for swaping energy provider. If I do swith to Octopus then I will use the link you sent me.
 

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Thank you very much. That is very useful. The Octopus energy sounds like a killer. I am assuming I need to switch my whole house energy provider. I am with British Gas at the moment, will find out their rates then give them a call to see the costs for swaping energy provider. If I do swith to Octopus then I will use the link you sent me.
You would switch from your current supplier to Octopus and would need a smart meter fitting, which Octopus will do for you at no charge. Then you can choose from their "time of use" tariffs. Go is the "easiest" to understand and work with and that would be where I would start. Agile 'can' save even more, but you have to willing to really work at it and also willing to gamble that sometimes it's more expensive.

Agile has worked out generally cheaper for us this last year, with a few months being much cheaper - but then we run two EV's and an ASHP for heating and hot water, so we're biiiig users.
 

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Does anybody know, if you charge your car in the winter and don't use the car for a week or two. Does the battery stay charged or does it lose some energy? Thanks a lot once again for your guidance.
 

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You would switch from your current supplier to Octopus and would need a smart meter fitting, which Octopus will do for you at no charge. Then you can choose from their "time of use" tariffs. Go is the "easiest" to understand and work with and that would be where I would start. Agile 'can' save even more, but you have to willing to really work at it and also willing to gamble that sometimes it's more expensive.

Agile has worked out generally cheaper for us this last year, with a few months being much cheaper - but then we run two EV's and an ASHP for heating and hot water, so we're biiiig users.
Thanks. I am just about to call British gas and Octopus to check the differences.
 

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E-Niro 64kWh '4' since 9/20 (was Prius)
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Discussion Starter · #228 · (Edited)
Does anybody know, if you charge your car in the winter and don't use the car for a week or two. Does the battery stay charged or does it lose some energy? Thanks a lot once again for your guidance.
It’s very good at retaining HV battery charge. During lockdown, I’ve left mine for over a month parked up, any loss of charge is very minimal and unnoticeable. Lithium Ion cells on their own typically have almost zero self discharge. It mainly depends how much draining load is connected to them. On this car, there must be some drain as the car powers itself on for just 20 minutes every day in order to help keep the 12V battery charged up. However this drain power is relatively small and it’s a big battery. I can’t verify this but if I was pushed to put a number on it, I would estimate that it’s around 1% SOC loss in a month of disuse.

BTW, although many do regularly keep their HV battery topped up to 100%, if you don’t need the full range it's theoretically much better for battery longevity to stay below 100% especially so if it is not to be used for a while. 80% is a frequently used target SOC for many. Similarly, frequently deep discharging the battery is not good for the theoretical longevity. And also you would get lots of range anxiety when getting too low, too often. So please understand that the published range figures are from 100% to 0% but in practice you would not typically use the full capacity from end to end, especially at the lower SOC end.

Re your office chargers, you need to ask what the charge rate is in order to assess how much SOC you can put back in in the four hours availability limit I think you described. Peter.

PS regarding Octopus, it is definitely the way to go (pun 😂) but you need a working SMETS2 smart meter for the smart tariffs. If you already have one, then great go right ahead. If you haven’t please be aware that Octopus have delays for installing Smart meters currently due to huge demand. It could even be quicker to get smart meter fitted by your present supplier, then switch to Octopus?
 

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BTW, although many do regularly keep their HV battery topped up to 100%, if you don’t need the full range it's theoretically much better for battery longevity to stay below 100%
Fully charged battery can’t make full use of regenerative energy. Thus, you get better efficiency during the initial miles by charging to 80% instead 100%.
Not a big issue in reality, but worth considering in daily commute if you don’t need the max range.

It’s like not accepting free candy from a stranger when offered.
 

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Excellent guidance. Thank you!

Yes, I have a smart metter already. It was installed by British Gas. British Gas mentioned today that they also have an EV package which 5.7p per kwh between 12am and 5am.
 

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E-Niro 64kWh '4' since 9/20 (was Prius)
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Discussion Starter · #231 · (Edited)
Excellent guidance. Thank you!

Yes, I have a smart metter already. It was installed by British Gas. British Gas mentioned today that they also have an EV package which 5.7p per kwh between 12am and 5am.
Great, but is it SMETS1 or SMETS2 type? The latter should work no worries if/when you switch, but the former almost certainly won’t as it is more or less supplier specific. If it was recently installed then it will be SMETS2. If switching you need to check.

I didn’t know BG had an EV tariff. That sounds reasonable but what is the daytime rate on that tariff?
GO is 13.3p daytime for me, but it varies a little on location I think. I have Go Faster rate which gives me 5h 20:30 till 01:30 at 5.5p.
Peter
 

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Great, but is it SMETS1 or SMETS2 type? The latter should work no worries if/when you switch, but the former almost certainly won’t as it is more or less supplier specific. If it was recently installed then it will be SMETS2. If switching you need to check.

I didn’t know BG had an EV tariff. That sounds reasonable but what is the daytime rate On that tariff?
GO is 13.3p daytime for me, but it varies a little on location I think. I have Go Faster rate which gives me 5h 20:30 till 01:30 at 5.5p.
Peter
I got curious as well. And holy s.....

19ppkW peak and 27p standing charge :eek:
 
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Discussion Starter · #233 ·
Fully charged battery can’t make full use of regenerative energy. Thus, you get better efficiency during the initial miles by charging to 80% instead 100%.
Not a big issue in reality, but worth considering in daily commute if you don’t need the max range.

It’s like not accepting free candy from a stranger when offered.
Sorry, but that isn’t true on Eniro. You still can use regen right from the start at 100% indicated SOC. There is a capacity buffer such that when it displays 100% there is still a little more capacity not filled up, so regen can still operate, even at 100%. Peter
 

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Discussion Starter · #234 ·
I got curious as well. And holy s.....

19ppkW peak and 27p standing charge :eek:
Hmmm, that sounds about right for BG trying to rip off the poor customer.
No contest then Octopus wins again. Rather better CS experience too, not to mention the £50 join up bonus, and exit anytime you like without penalty. 100% renewable and Go rate is capped for a year.
Peter.
 

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Sorry, but that isn’t true on Eniro. You still can use regen right from the start at 100% indicated SOC. There is a capacity buffer such that when it displays 100% there is still a little more capacity not filled up, so regen can still operate, even at 100%. Peter
Mild regen yes, but rapid charging and regen kW’s are limited when battery is almost full.
This should apply to all EV’s, some are of course more sensitive about this than others and driving styles make difference too.
 

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Discussion Starter · #236 ·
Mild regen yes, but rapid charging and regen kW’s are limited when battery is almost full.
This should apply to all EV’s, some are of course more sensitive about this than others and driving styles make difference too.
I see what you’re saying. I seem to recall reading that some EVs completely prevent all regen whist at 100% SOC. I must admit when experimenting some time ago I saw the max peak regen whilst braking hard down a steep hill was around 75kW iirc. Of course that won't have been at 100% SOC. It does seem logical that the max allowed regen on a 100% SOC battery will be reduced somewhat. At a guess I would say it will probably be around 25-30kW. I expect the peak regen power available will also be reduced when the battery is very cold (in the same way that rapid D.C. charging is....Coldgate)

I think I would argue that most folks driving normally wouldn’t notice this reduced regen at 100% SOC and obviously it won’t be very long before the SOC reduces and the maximum regen power available gradually returns.

For curiosity I might try it one day, though it’s not often I go above 80% (just occasionally to balance the cells). I do have some good hills to descend very near to home. Peter.
 

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It would only be a problem in the first place if you live at the top of a hill and every journey started with that downhill section.
 

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Discussion Starter · #238 ·
It would only be a problem in the first place if you live at the top of a hill and every journey started with that downhill section.
That pretty much describes my location :) . I’ve not noticed the effect yet.
I wouldn’t describe it as a “problem“ though, just a characteristic of note. Anyway, It’s a good thing to clean up the unused brake discs now and again! Peter
 

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Is there any way/app to keep track of the car stats/charging/efficiency etc?
previously I’ve used fuelly app to keep track of things on an ICE car.
uvo has some journey info but nothing about efficiency.
 

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Is there any way/app to keep track of the car stats/charging/efficiency etc?
previously I’ve used fuelly app to keep track of things on an ICE car.
uvo has some journey info but nothing about efficiency.
Nothing I've found, which saddens my inner-geek
 
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