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Discussion Starter #1
Does Ampera only consume the electricity it needs when charging? What I'm getting at is should I always charge every night, regardless of battery state safe in the knowledge that it will stop charging when full. I want to always leave home with a full charge but wont always return with an empty battery so I'm hoping I can just get in the habit of charging every night...

I'm also working out and comparing tariffs - how much will a full charge consume? 3.7Kw x 6 hours = 22kw/h a night? (if empty)
 

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Hi Derek,
It knows when to stop charging, so it's no problem to get into the habit of putting it on charge when you get home.
Also note that it only uses about 6A for normally charging for 6 hours, or 10A for about 4 hours if you tell it to (through a menu) or use the 16A-capable charging socket.
It's limited by the storage capacity of the battery which I believe is about 10.6kWh for a complete charge.
Cheers
Richard
 

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Discussion Starter #3 (Edited)
Richard,
Many thanks - thats good news. I am doing my figures assuming 16A charging (16A x 230V = 3.7Kw) and from what you say it may well take less than 4 hours then.
I am assuming that even if I fit a 32A capable charging unit (7KW) it will still only draw 16A (previous reply said the Ampera can only use 16A max?).
regards
Derek
 

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Also note that it only uses about 6A for normally charging for 6 hours, or 10A for about 4 hours if you tell it to (through a menu) or use the 16A-capable charging socket.
It's limited by the storage capacity of the battery which I believe is about 10.6kWh for a complete charge.
In my experience 6A charging takes about 10 hours for a full charge and about 6 hours at 10A. 16A takes about 4 hours.
 

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In my experience 6A charging takes about 10 hours for a full charge and about 6 hours at 10A. 16A takes about 4 hours.
Yes agree with these times. Plugged in when not driving and only charges what's needed to top up. Costs me about £1.20 for a full charge overnight.
 

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Discussion Starter #6
£1.20 for a full charge! surely not - what tariff can that be? From above:

Full charge at 16A x 230V x 4 hrs x 15.66p (my current tariff) = £2.30 or
Full charge at 10A x 230V x 6 hrs x 15.66p = £2.16 or
Full charge at 6A x 230V x 10 hrs x 15.66p = £2.16.

wishful thinking or have you found a super low tariff at around 8p?
 

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Hi Derek,
It knows when to stop charging, so it's no problem to get into the habit of putting it on charge when you get home.
Also note that it only uses about 6A for normally charging for 6 hours, or 10A for about 4 hours if you tell it to (through a menu) or use the 16A-capable charging socket.
It's limited by the storage capacity of the battery which I believe is about 10.6kWh for a complete charge.
Cheers
Richard
Even though the Ampera battery capacity is 10.6KWH it takes anything from 11.5kWHs to 12.5KWH to fully charge due to energy losses when charging.
Its cost me £1.23 +VAT to fully charge at home 11.5kwh x 10.65p price per KWH (my rate fixed until OCT 2014)
 

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I agree with the charge times mentioned.

I only ever plug in when it needs a charge and never leave it plugged in once it is fully charged.

Vauxhall suggest that it is left plugged in all the time and this will mean it can maintain an absolute 100% state of readiness but this is not at all necessary.
 

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Ampera will take more electricity when plugged in if its very cold. I think it must heat the battery if its -5C or below.
I left mine plugged in over 2 nights and had not driven it during the day and it had taken 15.6 Kwhs from the mains. Both nights were -5C
 

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I see you're in Waterlooville as well Derekb, does this mean I may at last see another Ampera in my travels locally? :) A key point was made earlier in the thread that you didn't take into account in your maths, which is that the Ampera isn't charging at 16A for the whole 4 hours. It's the total kwH consumed stated a couple of posts back which is the thing to use to calculate. I'm with Good Energy, so my electricity is relatively expensive, at 15.24p a unit, but even so, thats only a max of about £1.90 to fully charge the car from empty - less now I've got the solar panels.
 

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£1.20 for a full charge! surely not - what tariff can that be? From above:

Full charge at 16A x 230V x 4 hrs x 15.66p (my current tariff) = £2.30 or
Full charge at 10A x 230V x 6 hrs x 15.66p = £2.16 or
Full charge at 6A x 230V x 10 hrs x 15.66p = £2.16.

wishful thinking or have you found a super low tariff at around 8p?
Was 8.26 + vat is now 9.22 +vat so will be about £1.40 overnight now on Powerfuel tariff with Scottish Hydro.
 

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The other reason for leaving the vehicle plugged in during the winter is the preconditioning using remote start where it will use the mains to provide power for the heating rather than depleting the main drive battery. During the summer not so necessary to leaved plugged in.
 

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Discussion Starter #13
MikeH - that is a great tariff I will check that one out.

Mike Ball - Yes Denmead to be precise! I'm collecting an Ampera this friday (Cyber Grey too) - dont know what came over me! - just trying to do some homework.
 

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Denmead eh? Well, well - I'll keep an eye open for you, I go to and through Denmead often, and will do a bit more now Janine has opened her new wine shop!
 

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if you leave it plugged in it will take power occasionally to condition the battery. did you use the pre-heat?
 

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I've been looking through my recent charges, and a lot of them are 16kWh - when the car's completely empty. Feels a lot for a 10.5kWh usable portion of battery....?
 
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