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Discussion Starter #1
Hi All, Can anyone tell me... if i never plug it in to a mains supply, will the petol engine fully recharge the battery?
 

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Hi and welcome to the forum.

I asked this very question at the test drive on 25th November. The answer was clear...

When the car is running in ER mode, that is with the petrol generator running, it does not charge the battery. If you run the battery down to the point where the petrol generator needs to run then the battery will stay flat until you plug it in.

I thought that this was a pity because when driving at low speed there is going to be plenty of spare generating capacity from the petrol generator as not much is needed to drive the car.

I am sure this will become more clear int he coming months.
 

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Discussion Starter #3
Thanks for the quick reply. I am now wondering if I could get it to re charge itself if I put it in hill climb mode? The reason for my asking is that I will not be able to plug it into my home supply (and neither will anyone who live in a block of flats of terrace houses with no off street parking etc..) Surely this rules out a whole load of people who would like to buy this car
 

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SnaxMuppet said:
I thought that this was a pity because when driving at low speed there is going to be plenty of spare generating capacity from the petrol generator as not much is needed to drive the car.
I understand that, all spare capacity is stored in the battery nothing is not wasted. When driving at slow speeds the engine will run periodically. It will cut out when the battery is above its base level and turn on when the battery level falls below said level.

The engine speed will run at the slowest possible speed to generate just enough power for the motor, generating too much power and storing it incurs charging losses and reduces the efficiency further. The car operates on the just-in-time principle where power is provided when it is needed to avoid further losses. (keeping the fuel in the tank means no conversion and charging losses are incurred, conversion losses are incurred only when the power is needed and charging losses are reduced to a minimum by not charging.)

'spare generating capacity' would mean you are burning too much fuel! (energy cannot be created it is only converted from one form to another)

Mike.
 

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Rhubarb_15 said:
Thanks for the quick reply. I am now wondering if I could get it to re charge itself if I put it in hill climb mode? The reason for my asking is that I will not be able to plug it into my home supply (and neither will anyone who live in a block of flats of terrace houses with no off street parking etc..) Surely this rules out a whole load of people who would like to buy this car
You can drive it without charging but it would be daft. (very inefficient!)

You should bear in mind the Ampera is two cars in one. It is NOT the best electric car, and it is NOT the best petrol car. if you are only going to be using one fuel method you should buy a different car! the Ampera is only a good car when you combine both needs. It is a good day-to-day electric car with a petrol range extender. You should not think of it as a petrol car, its is supposed to be electric, and hence supposed to be charged.

Hence the name 'Electric' range extended car.

The Petrol Range Extender is not as efficient as a straight petrol car. Because the energy needs to be converted from mechanical from the engine to electrical energy, you get generating losses, and again converting from electrical back to mechanical at the wheel is also not perfectly efficient, and to add to that any surplus power that does go to the battery is subjected to charging losses too, making it even worse.

Perhaps a 100% petrol car like the Prius would suit your needs better.

There is not a single car on the road that suits every-ones needs, Just like an Aerial Atom is not suitable for anyone who does not have a garage (it has no roof!), the Ampera is not suitable for anyone who cannot charge it.


Mike.
 

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Discussion Starter #6
Crickey, you're a bit hot under the collar! I'm asking about the charging question because I want to know if it's possible, and from what you've said it sounds like it will. You assumed , wrongly, that MPG was a priority for me but its not! the 5%tax efficiency IS and it will be for loads of other company car drivers.Half the cost of a [email protected]% Companies pay for our petrol but wont pay for our electricity used to charge it (well maybe they will but the expense claim form will be overly complicated if our HR dept have anything to do with it)
So if it will recharge itself I will seriously consider it as it will save me £150 to £200 a month in Tax and I'm fed up of paying it. So the Ampera may well be suitable for people who will never plug it in. and we will use the pure electric power drive when we're in towns and cities and let it charge itself on motorways. Miles per gallon??? who cares!
An unintended consequence of our tax system against the motor vehicle.
 

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Sorry about seeming hot under the collar, I can be a tad blunt, don't take it personally. Yes the assumption I drew was wrong, but I'll put that down to the available information, as your intention is counter to the intended design, like using a hammer to put in screws.. (which incidentally does work!)

So under your circumstances the car would not recharge itself. All it would do is maintain the charge level. In normal driving mode the battery would be maintained at ~30% in 'Mountain' mode the battery would be maintained at ~45% (in theory you could change from normal to mountain and the car would charge-up its reserve to 45%) there is a third mode called 'Hold' this tells the car to maintain the battery at whatever level it is at, ie press hold at 90% charge and it will keep it, you can not however select a desired charge above what it is presently at (except mountain as above).

The reason for this is that it is more efficient to generate the power as and when needed rather than to store it.

So don't assume that running on the motorway will top up the battery.. if it is not efficient, it wont do it. At 70 mph you will find the engine will run at different speeds depending on the charge state. If charge is High the engine will run low, say 1000 rpm (saving fuel using excess charge) when the charge is low the engine will increase to a higher output say 3000 rpm and provide a small surplus to bring the charge level back, this uses more fuel for only a short period.

The engine speed is controlled purely by the current demand and the current charge state, it is not trying to top up all the time, but only when low. The only uncontrolled top-up is from regenerative braking, but this is soon consumed when you pull away again (the engine does not need to come on if the charge state is high due to regen top up).

So to conclude if you run it on petrol only, it will work. However it would not ever recharge (it will maintain 30%/45%) as it is not necessary to have a full battery.

You might want to bear in mind the car has a smaller petrol tank than a standard car, and because the petrol only mode is less efficient you will be topping it up more regularly.. You might find it beneficial to charge-up wherever possible.. maybe whilst at work/site. A full charge is only 4 hrs from a standard 13amp mains plug. I believe that the Ampera is not compatible with fast chargers (high current charging reduces battery quality/life).

the US EPA rating for petrol only driving is 37mpg (us gallon)
http://upload.wikimedia.org/wikipedia/c ... _Label.png


However if I were your employer I'd seriously consider whether it would be beneficial to pay you more to cover your personal tax on a different vehicle as an incentive to reduce your fuel consumption... as it might save money in the long run! (and give you a car with better range).

Mike.
 

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Rhubarb_15, I have to agree with parax. The Ampera will NOT charge the battery once the battery is below its low threshold at least it won't charge it much. As parax says, it will charge the battery a little bit if there is surplus but for all intents and purposes charging in this way is not going to be sufficient to run in EV only mode after. That is not the intention of the range extender.

It is only my opinion but as a Nissan Leaf owner I have given this considerable thought and IMO if anyone intends to run the Ampera on petrol most of the time them it is probably not really the right car for you. As parax says, it is a compromise. It is not the best EV and neither is it the best petrol car and if you intend to run on petrol most of the time then I am sure that you can get a all-petrol car with mpg figures much better than the Ampera's 51mpg on petrol only. Surely those petrol savings over the entire ownership could outway the tax benefits of the Ampera?

Don't forget... the more you plug in the better the mpg gets and the better the CO2 emissions get over the lifetime of the car.

Whether it is right for you only you can say but IMO it is not going to be a good car to run mostly on petrol.
 

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Discussion Starter #9
Thanks for the full explanaition Mike, and Apology totally accepted (you re not a troll). I'll still condider it as an option as it will save me a significant amout of money. I could point of the lackk of environmental friendlyness to my company but it's a big corporation with middle managers who dont really care about anything but how to get on in their careers so it would fall on deaf ears. The reason I pointed out the block of flats dwellings as excluded people is that I hope Vauxhall / GM see this as a big enough market segment to do something about it. I'm not sure what marget share sales reps actually represent in new car purchases? but it's probably not enough.. I saw on an Volt video that there will be charging stations which need 240 Volts, I wonder if there are any plans to bring such a system to the UK. Again, thanks for your interest and replys.
 

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Rhubarb, iif it works for you financially then fine but that is your choice... to take the money rather than the environmental benefits.

The issue surrounding who people will charge their EVs if they don't have private, off-street overnight parking is a big one that no one yet has resolved. I do know someone with a Nissan Leaf that has had it for months and NEVER charged at home. Instead he charges exclusively using public and Nissan dealer fast chargers. Fast charging may be a solution for cars that can be fast charged but the Ampera can only charge at 16A so fast charging does not apply.

I do not know what the answer to this one is yet and it seems that neither does anyone else but resolved it must be if EVs are to be accepted by the masses.
 

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Rhubarb_15 said:
The reason I pointed out the block of flats dwellings as excluded people is that I hope Vauxhall / GM see this as a big enough market segment to do something about it.
The Ampera only benefits from low BIK rates because you are supposed to plug it in! (BIK is proportional to CO2/km - Low CO2/km is only achieved by running the first 40 miles/day on electric) So what can Vauxhall 'do' about people in flats? Somewhat surprisingly, they do already make cars that don't need plugging in...
Perhaps your question should be; what are hmrc to do about EV BIK rates being abused by Petrol only use?

Rhubarb_15 said:
I saw on an Volt video that there will be charging stations which need 240 Volts, I wonder if there are any plans to bring such a system to the UK.
From what I understand all UK charging stations are 240v, it's just the available current that varies, the charging stations ecotricity have put in motorway services have a 13 amp (household style) mains plug (they may also have higher current options) I would also assume that the on-street chargers (mainly London) are the same, as are the NCP car park chargers.
From what I understand fast chargers are pretty rare (expensive to setup) and are usually at manned sites such as dealerships, and are no use to the Ampera anyway. So a suitable charging network already exists across most major towns and cities in the UK (Lincoln excluded as Top Gear went out of their way to point out!)
 

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Discussion Starter #12
Thanks Mike. I only get 33 to 36 mpg at the moment (3.0ltr Petrol car) so 37 is on the money for me, it just wont be as fast and I can live with not driving fast. I must be getting old ;)
On a change of Subject, have you read Bean counters V Car guys by Bob Lutz? He's Ex Vice Chairman of GM and goes into how they ended up in trouble as a company and the development of the Volt. He bigs himself up a lot but its an entertaining and illuminating read if you interested. Just a thought.
 
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