RE: BMW i3: Driven
Discussion
RandomTask said:
If Tesla can do 200-300 miles (albeit in something that weighs well over 2 tonnes) then I would have hoped that BMW could do better than 80-100 miles, which could be as little as 60 in the winter with light/heater turned on.
If they're going to offer a range extender version, why bother? What's the use case that benefits from a longer electric-only range that wouldn't be better served by a more conventional car anyway? Kong said:
This is going to sound really un-PH but I can't see why they needed to give it 170bhp? It's a city car with an 80 mile range, surely if it's hardly going to leave the city then 100bhp would be more than enough? In which case they could presumably made it even more 'eco'.
Not really, as:1) The battery size is pretty much set by the range requirement, which is set by the road load (aero + rolling friction). A big (in terms of energy capacity) battery naturally has a high power capability
2) The major losses in an electric machine primarily scale with current not power and so a larger Emachine is not a lot less efficient than a smaller one, even when only producing a proportion of its maximum output (unlike an IC engine). With only 1 fixed mechanical drive ratio (gear) this powertrain requires a high torque output to achieve acceptable gradability and low speed step-off performance)
3) To capture any meaningful braking energy (regen) requires a high system power capability (because you regularly stop a car much faster than you accelerate it!), so if you have a high power system to enable decent regenerative capture, then you automatically have a high power system for positive torque production
4) BMW are a "performance lead" brand. I don't think their marketing dept would sit happily with a "slow" car, whatever the market segment it were aimed at.......
It just seems to me that a lot of the manufacturers have passed the point of no return when it comes to electric vehicles, they are having to bring something out to illustrate where all the billions of R&D has gone. However, the tech just isn't there yet and this idea is something of a 'muddle-through' at this stage. The fact is elec cars will always be a petrol/diesel car compliment not a substitute until they can get battery weight down and improve the range/reduce charging time.
We all know how we feel when we go to pick up our mobile and it is out of charge, infuriating.
Regards,
MyCC.
We all know how we feel when we go to pick up our mobile and it is out of charge, infuriating.
Regards,
MyCC.
This vehicle demonstrates that battery weight is not the big issue.
I suspect that it will also demonstrate that battery cost IS the big issue (and hence the final vehicle cost)
The performance and capability of this car effectively put it broadly on par with a 118d, that you can buy for about £22k. The i3 i fear will be something closer to double that.............
I suspect that it will also demonstrate that battery cost IS the big issue (and hence the final vehicle cost)
The performance and capability of this car effectively put it broadly on par with a 118d, that you can buy for about £22k. The i3 i fear will be something closer to double that.............
If the reports that it will cost < 35k are true, than this could be very popular. I would love to own an good electric car (to go next to the m3) for commuting and general duties. With the range extender it would even work as a single car for lots of people. I would charge at work, but obviously that doesn't work in everyones situation.
For those who insist on trying to denigrate electric cars because 'they still use CO2!?!', take a rest. Try considering the car on it's merits and leave the social, ethical, environmental crap out of it. It has been years since hybrids and electric cars sold on these points alone.
For those who insist on trying to denigrate electric cars because 'they still use CO2!?!', take a rest. Try considering the car on it's merits and leave the social, ethical, environmental crap out of it. It has been years since hybrids and electric cars sold on these points alone.
wemorgan said:
MichelV: sounds like you're talking about an Audi A2 with a more modern engine. Back in the day the A2 1.2TDi was ~80mpg on the combined cycle.
Putting that aside, the i3 is still a great game changing in my eyes.
Ok that is scary, you need to change jobs and go work as a mind reader.Putting that aside, the i3 is still a great game changing in my eyes.
But that is exactly my point...and it would be the more risk averse route...
I agree with Chris on this. I am unsure whether the only electric route is the way we should be going until there is a properly sustainable way to generate and store electricity carbon neutrally.
I run a printing company and it annoys me that people assume producing something on paper should be damaging the environment when compared to the unknown environmental costs of the manufacture of electronic devices + Google searches + data servers + etc, etc. Paper is made of carbon (so captured in the wood pulp it's made from) easily reusable and recycled and sustainably farmed.
So the old debate. You do 10,000 miles a year of mixed driving. In holistic terms, what is more beneficial to the environment? A brand new hybrid or electric car, or a new small engined light weight, or even a quality used car which is likely to last 20 years+?
I run a printing company and it annoys me that people assume producing something on paper should be damaging the environment when compared to the unknown environmental costs of the manufacture of electronic devices + Google searches + data servers + etc, etc. Paper is made of carbon (so captured in the wood pulp it's made from) easily reusable and recycled and sustainably farmed.
So the old debate. You do 10,000 miles a year of mixed driving. In holistic terms, what is more beneficial to the environment? A brand new hybrid or electric car, or a new small engined light weight, or even a quality used car which is likely to last 20 years+?
Well done Chris for highlighting the whole absurd bs surrounding the Green Polemic, an economic Petrol car is far "Greener" if you actually did all the sums, honestly.
Point is, few people really are, too many fat snouts in the great Green trough and self righteous halfwits harping on about their CO2 emissions, Rainforests and cuddly Polar Bears to dare investigating the bottom line.
Greenness is the new age Religion, in place of a set of bizarre fairy stories that fundamentally illustrate the changing seasons of the year we are now ruled by a different bunch of utterly corrupted ideas, superficially well intentioned BS and Snake Oil Science.
/rant
Point is, few people really are, too many fat snouts in the great Green trough and self righteous halfwits harping on about their CO2 emissions, Rainforests and cuddly Polar Bears to dare investigating the bottom line.
Greenness is the new age Religion, in place of a set of bizarre fairy stories that fundamentally illustrate the changing seasons of the year we are now ruled by a different bunch of utterly corrupted ideas, superficially well intentioned BS and Snake Oil Science.
/rant
NGK210 said:
Chris Harris said:
...But just imagine an i3 with a 1.0-litre, 150hp motor that weighed 750kg and would do 100mpg. With a range of 600 miles. Now that would be something special.
Throw away 280kg of battery from 1200kg, then juggle the weights of the electric motor vs something like a Ford 1.0 ecoboost with all its gubbins + fuel for 600 miles and I fail to see how you end up down at 750kg. I also can't understand where the enormous leap in economy to 100mpg comes from when the Fiesta Ecoboost manages about 43mpg in the real world and doesn't have 150hp?
998420 said:
Well done Chris for highlighting the whole absurd bs surrounding the Green Polemic, an economic Petrol car is far "Greener" if you actually did all the sums, honestly.
Point is, few people really are, too many fat snouts in the great Green trough and self righteous halfwits harping on about their CO2 emissions, Rainforests and cuddly Polar Bears to dare investigating the bottom line.
Greenness is the new age Religion, in place of a set of bizarre fairy stories that fundamentally illustrate the changing seasons of the year we are now ruled by a different bunch of utterly corrupted ideas, superficially well intentioned BS and Snake Oil Science.
/rant
At least you acknowledge it as a rant, but no one is harping on about 'green' here except you. Is it necessary that someone brings it up on every single article about a hybrid or EV? The articles are not much better (as if it hasn't been discussed ad nauseum by mostly ill-informed commenters already), but at least it's only 1 paragraph. There will be more hybrids and there will be more EV's. In some cases they are 'greener' and in for some people they provide a much better experience / situation than an ICE car. Never having to pay for petrol for the daily commute is a nice start.Point is, few people really are, too many fat snouts in the great Green trough and self righteous halfwits harping on about their CO2 emissions, Rainforests and cuddly Polar Bears to dare investigating the bottom line.
Greenness is the new age Religion, in place of a set of bizarre fairy stories that fundamentally illustrate the changing seasons of the year we are now ruled by a different bunch of utterly corrupted ideas, superficially well intentioned BS and Snake Oil Science.
/rant
And of all the EVs released so far, the i3 looks to be the most promising. The i8 even more so!
Saw one of these hot weather testing in the South of France last week. Saw it twice in 3 days on almost exactly the same bit of road just outside Fontvieille.
First time I thought it was just some agency car with a stickered body but realised the second time what it was. Very nice but like the i8 which is also due this year much more. Same electrics but with a small engine to boost it's range/performance. Both will be really good but I doubt all electric is the future at the moment. Just too many issues to overcome.
First time I thought it was just some agency car with a stickered body but realised the second time what it was. Very nice but like the i8 which is also due this year much more. Same electrics but with a small engine to boost it's range/performance. Both will be really good but I doubt all electric is the future at the moment. Just too many issues to overcome.
kambites said:
WingNut said:
Did I get this right? 9 litres of fuel to increase the range from 100 to 180 miles? That's not very efficient is it?
About 40mpg... does sound rather pathetic for a dedicated range extender doesn't it? I'd have expected twice that. Hence, if your daily mileage is less than the EV only range you will have a very good overall efficiency, but start to use the R-EV mode and that average will fall. So, if you do many more miles than the EV range, you should look at getting an ICE vehicle instead.
For what is aimed at an urban/commuter segment, i think that is a very valid strategy. Effectively, if you know you're just going to commute in it, and never go over the max EV range, you just buy the EV version. If you think you might occasionally go over the EV range you add the range extender, accepting that at those times you might only be doing average mpg (your actual average MPG will however still be very good assuming you don't drive too far).
But, if you're a photocopier salesman, who drives 300miles a day, then you'd be better off getting a 118d as before!
Where are the losses?
40mpg in this on a "combined cycle" will be something of the order of, what, 20% efficiency? I know you can get something like 40% petrol to DC efficiency from a purpose designed petrol generator; surely DC->battery->DC->Kinetic isn't really only 50% efficient? I'd have guessed more like 80%!
40mpg in this on a "combined cycle" will be something of the order of, what, 20% efficiency? I know you can get something like 40% petrol to DC efficiency from a purpose designed petrol generator; surely DC->battery->DC->Kinetic isn't really only 50% efficient? I'd have guessed more like 80%!
998420 said:
Well done Chris for highlighting the whole absurd bs surrounding the Green Polemic, an economic Petrol car is far "Greener" if you actually did all the sums, honestly.
And have you? Done all the sums i mean? I have, and it simply isn't true than a ICE engine car is more efficient. Remember, an ICE engine has a thermal efficiency of approx 22% maximum and cannot recover ANY KE (kinetic energy) at all. An EV drivetrain is approx ~65% to ~70% efficient as a two way average (including charging losses, but not grid/generating losses)As we don't include the losses in refining and distributing liquid fuels in the Co2 statement this seems like a fair comparison.
In fact, studies demonstrate that when operated within their EV only range, a typical EV (Leaf, Ampera, i3) requires approximately 2 to 3 times less energy input at source than a ICE powered vehicle.
(remember, whilst efficiency is a useful value to compare, what we really care about is total energy consumption for a given journey!) For example, a car that is 100% efficient but requires say 1kWh / km is actually worse (for the planet/your wallet) than one that is only 50% efficient but only requires 400w/km)
In terms of Co2, the picture is more clowded, but conventional engined cars still need to have their raw materials transported around the planet etc. The best and easiest comparison is simply the price of the object. Excluding market forces (trendy items cost more!) then the price of a consumer item pretty much accurately reflects the effort that went into making it (and hence the Co2 released whilst doing so!) If the sales volumes were the same (which they are not) there is nothing particularly about an EV that makes it significantly more expensive than an ICE vehicle
NOTE:
two ways losses make for slightly tricky comparison. For a conventional car, when you brake, all the energy stored in the car as KE is lost completely and irretrievably to heat. So it is 0% efficient in this mode, but generally, up till now we have ignored this. For an EV, where it can re-capture a proportion of the KE back to electricity in the battery, this recovery must incur some losses. As such and EV powertrain actually moves approximately twice the total energy around for any given drive cycle. And we really need to divide the losses by this total energy flux to get to a sensible average efficiency number.
Edited by anonymous-user on Wednesday 10th July 18:43
Chris Harris said:
Specialness is something that pervades all aspects of the i3 though. People will flock to it because the cabin, suicide rear doors and packaging are exceptional. It redefines urban chic. That it is powered by electric motors is almost incidental. I'm still trying to work out if BMW intended it to be that way.
Spot on. If car makers are trying to sell alternative tech, nobody's going to buy it on the merits of what is a, let's be honest, "unconvincing" technology ie electricity. They need something else to attract them, I think.Very impressed at the thought that's gone into this one from BMW.
NGK210 said:
Chris Harris said:
...But just imagine an i3 with a 1.0-litre, 150hp motor that weighed 750kg and would do 100mpg. With a range of 600 miles. Now that would be something special.
An interesting debate, and a very interesting time for car makers and consumers alike.
kambites said:
Kong said:
This is going to sound really un-PH but I can't see why they needed to give it 170bhp? It's a city car with an 80 mile range, surely if it's hardly going to leave the city then 100bhp would be more than enough? In which case they could presumably made it even more 'eco'.
That's a very valid point. Does seem a bit odd for this sort of vehicle. As somebody has already talked about dedicated petrol generators it is clear it is something regular people think about, it follows that the pros would have thought of this too. So why no application of existing technology?
Edited by KM666 on Wednesday 10th July 21:27
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