Reverse engineering the i3 @ Munro

[I33t]

But a car that gets almost the same mpg despite weighing 28% or 750 lbs more is the more efficient car

A car is a car. The most efficient car is the car that consumes less energy travelling a certain distance. The i3 is the most efficient EV currently available, including both lighter and heavier competitors.

If you watch the video linked at the beginning of this thread, you will be exposed to some of the design and production differences between your Golf and the i3 from a third party POV. You are welcome to not notice or see any of them.

Then, if you re-read the BMW service manager comment, you will see that he is not a just a BMW service manager, he is a VW/BMW dealer Service manager. Clearly, he has had the opportunity to consider both vehicles and he has an opinion. You and I may not agree with him, but I suspect the poor acceleration of the e-Golf compared to the i3 is the primary source of his comment. My FF Golf runs 0-100kph under 7 seconds, and changing it for an e-Golf with a 10 second time would be a substantial disappointment.

The e-golf forum is a little slow at the moment, but in due course it will become busier. Patience.

 

[Stevei3]

VW in the e-golf has gone the route of ultra high strength fused steel panels to narrow the carbon weight gap by 50+ pounds, and their ownership in a carbon fiber company and the XL1 shows a strong interest but for now are playing it safe with the e-golf
Ron

Hi Ron,
excellent that you're a happy E Golf driver, I'm sure it's a good car. Question though: could you eleborate about the Golf being just 50+ pounds heavier ? According to my info, curb weight is 3391 vs 2,634 lb.
Regards, Steven

 

[mrsmith]

Really is horses for courses - BMW and VW have taken two very different approaches to the same problem.

BMW have gone all in looking into new materials and manufacturing processes, with a big focus on light weight and low carbon footprint from birth. They have created a whole new production system including factories for the i3/8!

VW had planned an electric version into their standard series production vehicle, which is a brand new platform (MQB?) designed to work with many different power sources. It uses a conventional design and production techniques and materials, with the eGolf rolling off the same line as petrols and diesel versions.

Neither is the 'best' way, just different, for me a a VW golf was never on the cards (I wasn't even looking to replace my car, and was an electricskeptic, and not into 'utility' vehicles). However the whole ethos of the BMW project got me interested, and the test drive sealed the deal. I do like rear wheel drive too! That's just me.

As I'm in the UK I had a go in a Nissan leaf and a Renault Zoe, both were what I would call 'utility vehicles' and from a design, look and feel standpoint, just left me cold. The Zoe in particular felt like a let down on opening the door and getting in, I didn't want it.

The BMW had the opposite effect, I love the rear doors, amazing turning circle, GTi acceleration and find the size perfect for my family of four (7 and 11 year old boys).

The VW is one I may have been interested in but it feels too normal for me. I think if I had to choose something other than the i3 (Tesla excluded) I would go the Mercedes Electric B-class route. Looks a much better package than the Golf to my eyes and has a bit of speed too (still front wheel drive though)! The Audi A3 etron also looks interesting but has a petrol engine. However none of the above Germans were available when I ordered the i3.

I for one am glad that we have such a good choice of EV vehicles in 2015, and think us pioneers should stick together! The comparisons above all sounds a bit like splitting hairs

BTW, in the UK the VW eGolf in the same price as an i3 BEV!

 

[cove3]

Steve, reread my post where I said i3 has a 750lb advantage 2635 to 3391. 200 of that is a smaller battery, 150 is a smaller car, and 400 is the use of aluminum frame and carbon body. What I estimated from my reading was that VW tried to narrow that 400 lb carbon advantage by using lighter weight high strength steel fused panels.

This narrowed the advantage by 50-75 lbs, but still i3 is 325-350 lbs lighter due to choosing aluminum/carbon, but this comes at a pretty high cost and partially explains the 9600 US MSRP difference

Ron

 

[cove3]

My final thoughts:

1. i3 is most epa efficient in the sub compact category both mpg and kwh/100 miles
2. e-Golf is most epa efficient in the compact category
3. But the differences are really narrow and both have a similar range
4. One way to "normalize" for efficiency across categories (size) is to compare weight divided by kwh/100 miles, that is how efficient is it for the weight it's carrying around. By this measure, the e-Golf is more efficient.
(a) i3 2635lbs at 27 kw hrs/100 miles = 97 lbs/kw hr
(b) e-Golf 3391lbs at 29kw hrs/100 miles = 116 lbs/kw hr

I remain unconvinced that i3s ground up design resulted in a more efficient car than VWs MQB modified ground up design, and that the differences are in the cost tradeoffs, choice of car size, and choice of materials rather than the result of ground up design. The decision to use the Golf MQB platform precluded the use of carbon and determined the size, but there must have been enormous savings from the huge ice volumes

Also that the e-Golf is not a dog compared to the i3, the Golf having won Motor Trend, Detroit Auto Show and Green Car Reports car of the year, as well as numerous favorable e-Golf i3 comparison reviews. It is a few seconds slower 0-60 due to weight, but that narrows 0-35 and for me has more than enough acceleration.

Ron

 

[websterize]

…Designing that car with steel rather than carbon fiber will also result in a heavier car but it will also contribute to the car costing 9600 msrp less.

For some who took delivery of the i3 in late 2014, this was moot. There were many :shock: deals.

The Golf is a sharp car. I really enjoyed the TDI version.

 

[cove3]

<<<Could go the Mercedes Electric B-Class route. Looks a much better package than the Golf to my eyes and has a bit of speed too (still front wheel drive though)! The Audi A3 etron also looks interesting but has a petrol engine>>

I looked at the MB B Class, but the 3950 lbs, 44,000 price and the use of Class B chassis shoehorned for electric made it seem an afterthought compliance car rather than an ev commitment and ruled it out for me.

I am looking very hard at the AudiA3 e-tron for a road car due summer of 2015. I like the 3400 lb weight, looks, and 1st drive reviews so far. It appears to be VW groups plug in hybrid choice for the US market with the GTE remaining Europe only. My two 5 series BMW's are now 22 and 26 years old, and while neither have ever given me any problem and are cheap insurance without comprehensive, it's may be time for an upgrade.

Ron

 

[Sparky]

I have friends that wanted an A3 eTron and were told by a dealer that's it's not available here for another 12 months.

 

[mrsmith]

I looked at the MB B Class, but the 3950 lbs, 44,000 price and the use of Class B chassis shoehorned for electric made it seem an afterthought compliance car rather than an ev commitment and ruled it out for me.

Interestingly the BMW, VW and Mercedes are all pretty much the same price in the UK. Around £27K after the Government grant is applied.

 

[cove3]

<<<You are right and I am wrong. i didn't drive the i3 long enough to be able to compare the two approaches and form a judgement. <<

Regarding the 4 e-Golf regen settings vs 1 for the i3, after driving my car, what I originally said is true. The i3 has 1 level and the e-Golf has 4 levels (1,2,3+B), in addition to Level 0 (D) no regen at all (coasting). While it's true you can feather the i3 accelerator to in effect get a continuous degree of braking, you can also do this WITHIN each of the 4 e-Golf regen settings. So in that regard, I'd say the e-Golf regen is more versatile.

I know my wife wouldn't be comfortable beyond level 1 or 2 at most, and at those levels there wouldn't be much if any feathering to learn.
Ron

 

[Sparky]

The strength of regen also varies with comfort, and eco pro.

 

[DR61]

This is an interesting discussion. I am researching EV's for a future purchase but I have yet to drive either the i3 or e-Golf. I would like to be able to control regen so that I can make the car coast with zero regen when I want. The shifter regen control on the e-Golf does sound attractive, since I am a long-time manual gearbox driver. On my current plug-in hybrid (C-Max Energi), I can't easily control regen with the accelerator pedal, so to coast I shift to 'N' and to get max regen I shift to what Ford calls 'L'. It is a bit clumsy to do this however.