"Today, the sky has a blue appearance to my eye."
I agree though, let's hear it from all angles. Next time I'm in LA Socal, I'd like an extended ride in your Karma. I have a finely-calibrated butt-dyno
Haha, no worries. Let me know.
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Karma -vs- Model S
- Thread starter doug
- Start date
Haha, no worries. Let me know.
SByer
'08 #383
Likes of looks are subjective (well, everything is, really...), and we've covered the Karma's polarizing looks many times. I'm on the 'can't stand it' side*, but I still really appreciate SoCalGuy's detailed review.
I also think our own personal prioritizations color things tremendously. I value how the drive-y bits works far more than interior materials or 'luxury' (not that the 911 has either, really, IMO ;-). When I compare the Roadster to the 911 in my mind, the drive-y bits dominate - and there the Roadster kills. The interior? I can see where some people think the Roadster interior is 'cheap' - I find it Zen (and funny - I love the irony of my '08's stick). So I recognize my own confirmation bias, but I'm happy, so I'll stick with it ;-).
For me, with my drive-y bits priority, Model S vs. Karma is a no-brainer. But I appreciate that the only person for whom that opinion is really relavant is me. C'est la vie.
(*) Yes, I've seen it in person. Just about everything falls over the line of 'over self indulgent designer' for me, but I've also have a career that has really, really sensitized me to that kind of thing. I find the front end smirk even worse in person (I just can't un-see it), and the (negative) surprise for me in person was the fat-cat-belly droop in the midsection from a side view. Nobody that likes the car is likely to ever see either of those two things. I'm also probably pre-disposed to seeing things like that on the car because I don't think the engineering on it is up to snuff - have you seen pictures of those cheap looking, nasty motors? Seeing pictures of Bieber's chromed atrocity - which just accentuates all the visual negatives I see in the car - didn't help.
In the end, I want to see more efficient electric miles. So, what's the Fisker's nominal Wh/mi? It's got to be better than the Coda's, which looked shoddy in person and really, really, made the quality-oriented engineer in me weep...
I also think our own personal prioritizations color things tremendously. I value how the drive-y bits works far more than interior materials or 'luxury' (not that the 911 has either, really, IMO ;-). When I compare the Roadster to the 911 in my mind, the drive-y bits dominate - and there the Roadster kills. The interior? I can see where some people think the Roadster interior is 'cheap' - I find it Zen (and funny - I love the irony of my '08's stick). So I recognize my own confirmation bias, but I'm happy, so I'll stick with it ;-).
For me, with my drive-y bits priority, Model S vs. Karma is a no-brainer. But I appreciate that the only person for whom that opinion is really relavant is me. C'est la vie.
(*) Yes, I've seen it in person. Just about everything falls over the line of 'over self indulgent designer' for me, but I've also have a career that has really, really sensitized me to that kind of thing. I find the front end smirk even worse in person (I just can't un-see it), and the (negative) surprise for me in person was the fat-cat-belly droop in the midsection from a side view. Nobody that likes the car is likely to ever see either of those two things. I'm also probably pre-disposed to seeing things like that on the car because I don't think the engineering on it is up to snuff - have you seen pictures of those cheap looking, nasty motors? Seeing pictures of Bieber's chromed atrocity - which just accentuates all the visual negatives I see in the car - didn't help.
In the end, I want to see more efficient electric miles. So, what's the Fisker's nominal Wh/mi? It's got to be better than the Coda's, which looked shoddy in person and really, really, made the quality-oriented engineer in me weep...
I agree with you on efficiency - Model S is better in that regard. Using EPA numbers....
Fisker Karma = 32 miles range / 20 kwh = 1.6 miles per kwh
Tesla Model S = 265 miles range / 85 kwh = 3.1 miles per kwh
I think most of that has to do with the lighter weight (The Model S being about 700 lbs lighter, or roughly 87% of the Karma's weight) and better drag coefficient (remember, about half of the energy used to move a car is used to push air out of the way). The Karma's is 0.31 (still better than all Ferrari's btw) while the Model S is 0.24, nearly 25% better than the Karma. The remaining differences probably are comprised of wheel size (smaller wheels are more efficient, the Karma has 22's and the Model S has 19's), and motor efficiency (which I think also has to do with induction vs. PM tech).
For reference, here are some other stats:
Nissan Leaf = 73 miles / 24 kwh = 3.0 miles per kwh (0.29 cd, 3,401lbs)
Coda Sedan = 88 miles / 34 kwh = 2.6 miles per kwh (n/a cd, 3,682lbs)
Chevy Volt (2013) = 38 miles / 16.5 kwh = 2.3 miles per kwh (0.28 cd, 3,781 lbs)
From Tesla's Roadster Efficiency and Range spreadsheet ( found here Roadster Efficiency and Range | Blog | Tesla Motors ):
At 56 mph:
tires are 24% of energy used
aerodynamics are 41%
drivetrain is 34%
At 66mph:
tires 20%
aerodynamics: 48%
drivetrain: 31%
Vehicle weight, tire size and tire choice all contribute to the tire portion.
Aerodynamics is all Cd * frontal area. ( comparing just Cd is not sufficient )
Drivetrain includes the motor efficiency, inverter efficiency, bearings and gearing.
The mechanical drivetrain in the Karma ( 2 motors, mounted longitudinally ) may be more complex and have more losses than the Tesla one ( one motor, transverse with just a reduction gear ).
stopcrazypp
Well-Known Member
To be fair, I don't think most Karma buyers care about the efficiency and it's selling perfectly fine despite the low electric efficiency. I think Fisker will have trouble though if the Atlantic is not drastically better in efficiency, but that's a topic for a separate thread.
I think Fisker can improve both the weight and the drivetrain efficiency without compromising the looks (maybe some small "invisible" aero tweaks too) and that it would help overall efficiency significantly. I think part of the problem though is Fisker has an ICE and that needs significantly more cooling than just a battery pack and electric motor(s) alone, which necessarily compromises the Cd of the vehicle.
I think you're correct on this front. I have a feeling that the inverter + 2 electric motors + differential weigh a lot more than Tesla's integrated single motor+inverter, my wildly speculative guess is that Fisker could prob save 200-300 lbs on that front. Getting a new, dedicated, purpose-built range extender (maybe like the two-cyl going into the BMW i3) which has an integrated generator and smaller footprint could also shave off some weight off of the current 550lbs (est) worth of Ecotec + generator. A hybrid battery using the higher density Tesla chemistry and a front end using higher power A123 could also reduce weight/provide more energy storage. I suspect on those fronts alone, Fisker could probably shave off 600+lbs. Those Brembos are also pretty heavy and are probably oversized for the car (another 50-100lbs of savings).
Cool stuff. Has Tesla ever provided a weight audit to show where all the mass comes from? Does anyone know where one might be able to find a generic weight audit (e.g. 18' wheels X lbs, tires Y lbs, brakes, Z lbs, 4-cyl engine B lbs, etc)?
That information is really only useful to Tesla and their competitors. I am sure Tesla has this report and pays close attension to it, just like any automaker. Don't expect them to publish it however.
GSP
A so-so Karma review from CNN. http://money.cnn.com/video/pf/2012/08/08/pf-w-fisker-karma-review.cnnmoney?source=cnn_bin
The reviewer makes many comparisons with the Model S.
The reviewer makes many comparisons with the Model S.
bonnie
I play a nice person on twitter.
I totally agreed with his comments on styling ... not subtle, 'a cake with too much icing'. I know I'm in the minority, but nice to find someone over in this corner with me.
Raffy.Roma
Rome (Italy)
I agree, @brianman. The cost of things reflects the resources used producing and installing them. (Note that I said cost, not price.) These car-top PVs cost far more than the value of the power they'll ever put out, so installing them simply wastes resources -- quite the opposite of the "first R": reduce, reuse, recycle.
Plus, they'd garble the view through the pano roof!
Plus, they'd garble the view through the pano roof!
Raffy.Roma
Rome (Italy)
For the time being you are right but I read that new solar cells technologies will be available in future. Then the math regarding solar cells could turn in favour of including them on the vehicle.
That might be in the year 8 million. Let's wait until it's here before we worry about what to do with it. We may not even be driving cars by then.
My response is perhaps strong because I find this troubling:
People here and elsewhere have all kinds of wishes and demands for Tesla on the Model S. Can we at least constrain the TMC requests to good ideas?
If you think the tech will be ready in time, feel free to request it for the Model X. Solar cells are not ready for reasonable use on the Model S roof.
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