RE: MINI Cooper E

Author
Discussion

XitUp

7,690 posts

203 months

Friday 19th December 2008
quotequote all
RobCrezz said:
fastgerman.com said:
It's all about hydrogen though as Honda are doing.
I agree, electric motors will be the future, but the electric will come from hydrogen fuel cells.
Batterys are just too heavy and take too long to charge.
You're both wrong. See all the other topics on this for details wink

kambites said:
astrsxi77 said:
Ah yes and the safe recycling of batteries will, no doubt, use absolutely no energy whatsoever!
And the recycling of internal combustion engines doesn't (when it's done at all)?

And petrol takes no energy to extract, refine and ship?
Win.

XitUp

7,690 posts

203 months

Friday 19th December 2008
quotequote all
NiallOswald said:
daninsidious said:
I would imagine that the Honda Clarity will render this obselite in the long run?
Why so?
Because Top Gear said so, it must be true rolleyes

herewego

8,814 posts

212 months

Friday 19th December 2008
quotequote all
NiallOswald said:
herewego said:
NiallOswald said:
* G-Wiz, Tesla or anything in between - they're pretty much all in the region of 10-20 kWh/100km and our current electricity mix produces about 500g/kWh giving 50-100g/km which compares pretty well to the current average of ~180g/km for new cars.
I can imagine 10kWh/100km for the G-Wiz, but 20 for the Tesla doesn't sound right to me. I would have expected probably double that consumption smply because the car is heavier and people will be accelerating quicker and reaching higher speeds. Do you know the energy required to charge the car and the real world mileage? I don't mean Tesla's figures obviously.
I'm going by the figures given in David McKay's book.

David McKay said:
Manufacturers always quote the best possible performance of their products. What happens in real life? The real-life performance of a GWiz in London is shown in figure 20.21. Over the course of 19 recharges, the average transport cost of this G-Wiz is 21 kWh per 100 km – about four times better than an average fossil fuel car. The best result was 16 kWh per 100 km, and the worst was 33 kWh per 100 km. If you are interested in carbon emissions, 21 kWh per 100 km is equivalent to 105 gCO2 per km, assuming that electricity has a footprint of 500 gCO2 per kWh.
David McKay said:
The Tesla Roadster 2008 has a range of 220 miles (354 km); its lithium-ion battery pack stores 53 kWh and weighs 450 kg (120Wh/kg). The vehicle weighs 1220kg and its motor’s maximum power is 185 kW. What is the energy-consumption of this muscle car? Remarkably, it’s better than the G-Wiz: 15 kWh per 100 km.
If the real-world range was as bad as 105 miles, that'd be ~30 kWh/100km which still compares pretty well to the G-Wiz.
Does he say where his 15kWh/100km comes from? Just for starters we don't know what it took to charge the 53kWh battery.
The G-Wizz look more realistic because they've obviously run many charge recharge cycles so they will have been measuring the input energy.
Do you have any idea what levels of braking energy recovery they have? That could make a big difference.

Wolfsbait

464 posts

209 months

Friday 19th December 2008
quotequote all
sleep

And the award for the most mind numbingly boring thread ever goes to...

I know, I know, if you don't like it, don't read it....but seriously guys, this site should change it's name to VoltHeads...!

Edited by Wolfsbait on Friday 19th December 14:59

XitUp

7,690 posts

203 months

Friday 19th December 2008
quotequote all
Wolfsbait said:
sleep

And the award for the most mind numbingly boring thread ever goes to...

I know, I know, if you don't like it, don't read it....but seriously guys, this site should change it's name to VoltHeads...!
So, why did you read it?

PJR

2,616 posts

211 months

Friday 19th December 2008
quotequote all
Wolfsbait said:
sleep

And the award for the most mind numbingly boring thread ever goes to...

I know, I know, if you don't like it, don't read it....but seriously guys, this site should change it's name to VoltHeads...!

Edited by Wolfsbait on Friday 19th December 14:59
P!ss off then? Some of us do find it interesting. No doubt there are things that you find interesting that many other folk would not. Horses for courses n all that.

P,

Wolfsbait

464 posts

209 months

Friday 19th December 2008
quotequote all
Consider my coat on and the keys to my petrol powered car firmly placed in my hand...

getmecoat

NiallOswald

326 posts

205 months

Friday 19th December 2008
quotequote all
herewego said:
Does he say where his 15kWh/100km comes from? Just for starters we don't know what it took to charge the 53kWh battery.
The G-Wizz look more realistic because they've obviously run many charge recharge cycles so they will have been measuring the input energy.
Do you have any idea what levels of braking energy recovery they have? That could make a big difference.
As far as I can tell, it's just 53kWh/354km. Cycle efficiency of Li-Ion batteries is something in the region of 99% and AC propulsion (who provide the technology used in both the MINI and the Tesla) quote greater than 93% efficiency for their battery charger at 10kW charge rate. I don't know if that includes losses in the battery or not, so call it 90% worst-case plug-to-battery. 16.7kWh/100km in that case.

The G-Wiz source data is here. No idea how much energy either can actually recover under braking. AFAIK the Tesla only has regen braking on the rear wheels*, but even if the front wheels were electrically braked, I don't think the battery could accept the 220kW (average - peak will be even higher) required to stop 1450kg from ~70mph in 3 seconds.

Wolfsbait - why not go into one of the marque-related sections of PH and tell them you're not interested in XYZ car so can they please stop discussing it wink

  • so maybe 25% of braking power? Dunno what the F:R weight distribution is, or how much weight transfers to the front under braking.
Edited by NiallOswald on Friday 19th December 16:33

herewego

8,814 posts

212 months

Friday 19th December 2008
quotequote all
NiallOswald said:
herewego said:
Does he say where his 15kWh/100km comes from? Just for starters we don't know what it took to charge the 53kWh battery.
The G-Wizz look more realistic because they've obviously run many charge recharge cycles so they will have been measuring the input energy.
Do you have any idea what levels of braking energy recovery they have? That could make a big difference.
As far as I can tell, it's just 53kWh/354km. Cycle efficiency of Li-Ion batteries is something in the region of 99% and AC propulsion (who provide the technology used in both the MINI and the Tesla) quote greater than 93% efficiency for their battery charger at 10kW charge rate. I don't know if that includes losses in the battery or not, so call it 90% worst-case plug-to-battery. 16.7kWh/100km in that case.

The G-Wiz source data is here. No idea how much energy either can actually recover under braking. AFAIK the Tesla only has regen braking on the rear wheels*, but even if the front wheels were electrically braked, I don't think the battery could accept the 220kW (average - peak will be even higher) required to stop 1450kg from ~70mph in 3 seconds.

Wolfsbait - why not go into one of the marque-related sections of PH and tell them you're not interested in XYZ car so can they please stop discussing it wink

  • so maybe 25% of braking power? Dunno what the F:R weight distribution is, or how much weight transfers to the front under braking.
Edited by NiallOswald on Friday 19th December 16:33
I didn't mean to turn into twenty questions, I just thought there might be some real data out there but apparently not. The Tesla raises interest at any rate.

artov60

413 posts

189 months

Sunday 21st December 2008
quotequote all
AlpineWhite said:
kambites said:
I think an internal combustion powered car is about 20% efficient under normal driving conditions.
More like 35% I'm lead to believe; but if your figures on power stations are right then they still appear to better the IC engine.
It is amazing that people believe that burning a gallon of petrol to make electricity and then transferring it across the grid and then charging a battery will take a car further than burning petrol directly in an internal combustion engine. There is some green propaganda around but that one is quite incredible. Well done!

XitUp

7,690 posts

203 months

Sunday 21st December 2008
quotequote all
artov60 said:
It is amazing that people believe that burning a gallon of petrol to make electricity and then transferring it across the grid and then charging a battery will take a car further than burning petrol directly in an internal combustion engine. There is some green propaganda around but that one is quite incredible. Well done!
Where is this petrol fueled power station you are talking about? Does it need high octane or will the cheap stuff do?

PJR

2,616 posts

211 months

Sunday 21st December 2008
quotequote all
artov60 said:
AlpineWhite said:
kambites said:
I think an internal combustion powered car is about 20% efficient under normal driving conditions.
More like 35% I'm lead to believe; but if your figures on power stations are right then they still appear to better the IC engine.
It is amazing that people believe that burning a gallon of petrol to make electricity and then transferring it across the grid and then charging a battery will take a car further than burning petrol directly in an internal combustion engine. There is some green propaganda around but that one is quite incredible. Well done!
Read thread first, then post.

P,

kambites

67,461 posts

220 months

Sunday 21st December 2008
quotequote all
artov60 said:
AlpineWhite said:
kambites said:
I think an internal combustion powered car is about 20% efficient under normal driving conditions.
More like 35% I'm lead to believe; but if your figures on power stations are right then they still appear to better the IC engine.
It is amazing that people believe that burning a gallon of petrol to make electricity and then transferring it across the grid and then charging a battery will take a car further than burning petrol directly in an internal combustion engine. There is some green propaganda around but that one is quite incredible. Well done!
I don't think we have many petrol fired power stations, but if we did and they could manage the kind of thermodynamic efficiency that other modern stations do, it would be more efficient.

Internal combustion engines are really not very good at converting chemical energy into kinetic energy; especially when their output is tied directly to the energy needed by the vehicle rather than to some kind of energy storage system.

Edited by kambites on Sunday 21st December 18:39

NiallOswald

326 posts

205 months

Monday 22nd December 2008
quotequote all
artov60 said:
It is amazing that people believe that burning a gallon of petrol to make electricity and then transferring it across the grid and then charging a battery will take a car further than burning petrol directly in an internal combustion engine. There is some green propaganda around but that one is quite incredible. Well done!
I find it more amazing that you'd post something like this without offering any kind of evidence to support your claim rolleyes

kambites said:
Internal combustion engines are really not very good at converting chemical energy into kinetic energy; especially when their output is tied directly to the energy needed by the vehicle rather than to some kind of energy storage system.
Not to mention that most of the time, petrol engines in cars are operated a long way from their most efficient operating point.

EDIT: That is pretty much what you said...

Edited by NiallOswald on Monday 22 December 14:51

kambites

67,461 posts

220 months

Monday 22nd December 2008
quotequote all
NiallOswald said:
EDIT: That is pretty much what you said...
Indeed. smile

dandarez

13,246 posts

282 months

Monday 22nd December 2008
quotequote all
I find the topic of 'electric' cars interesting from one viewpoint only: I'm interested in cars and 'any' motive power source for them.

As from the 'green' viewpoint, No. It's a big business bandwagon and 90% b*ll*cks.

Someone above mentioned 'there is some green propaganda around'

I'd reword that to 'there is incredulous bucketloads of green propaganda around'.


AnotherClarkey

3,589 posts

188 months

Monday 22nd December 2008
quotequote all
dandarez said:
I find the topic of 'electric' cars interesting from one viewpoint only: I'm interested in cars and 'any' motive power source for them.

As from the 'green' viewpoint, No. It's a big business bandwagon and 90% b*ll*cks.

Someone above mentioned 'there is some green propaganda around'

I'd reword that to 'there is incredulous bucketloads of green propaganda around'.
I pretty much agree but if they also mean that we can reduce consumption of a finite fossil fuel resource and become a bit more independent of the politics of the middle east I wouldn't complain.

Plus, I reckon they could be great to drive after a bit of development.

Talksteer

4,843 posts

232 months

Monday 22nd December 2008
quotequote all
dcb said:
AlpineWhite said:
But you're probably right. Perhaps it will be the next Prius. The wider public will probably miss the fact that they're plugging it into the end of a coal power station anyway.
At best, any electric car can only move the supposed problem upstream
to the local electric power station.
But is that actually a bad thing, there is far more potential to run the national power network on clean/none oil based sources than there is to get fuel for cars from clean/non oil based sources.

With our current national grid energy mix the well to wheels efficency of the power station and national grid is superior to that of conventionally powered vehicles. Were we to go to an 80% nuclear mix like the French have done it would be much cleaner.

http://www.teslamotors.com/efficiency/well_to_whee...

Personally I think the Chevy Volt is the model to go with, because it only goes the first 40 miles on electric it doesn't take that long to charge up and if you go further than 40 miles (most journeys don't) or forget to charge it up you have the engine. Also 40 miles worth of battery, tiny engine and fuel tank are probably still a fair bit lighter than 200 miles of battery.


herewego

8,814 posts

212 months

Monday 22nd December 2008
quotequote all
dandarez said:
I find the topic of 'electric' cars interesting from one viewpoint only: I'm interested in cars and 'any' motive power source for them.

As from the 'green' viewpoint, No. It's a big business bandwagon and 90% b*ll*cks.

Someone above mentioned 'there is some green propaganda around'

I'd reword that to 'there is incredulous bucketloads of green propaganda around'.
It's a scientific bandwagon and some businesses jumping aboard doesn't invalidate it.

lance1a

1,337 posts

197 months

Monday 22nd December 2008
quotequote all
It's all politics and BS. BMW developed the Mini E to comply with Californian emmission legislation, now controlled by Arnie, who, in hindsight, gave us the frigging Hummer! It's only about the tax breaks. BMW could care less about the environment, as long as the shareholders get their dividends their happy.