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Discussion Starter #1
There's a lot more to a car than a table of numbers, but I wanted to share my compilation of specs on the Bolt EV and it's competitors. In the spec sheet for the Bolt EV, GM listed it's competitors as the LEAF, i3, Focus Electric, Soul EV, e-Golf, and B250e. I also included the Spark EV, the compliance car that is in many ways a Bolt prototype; the Volt PHEV; and Tesla Model 3 (in spirit). For good measure, I also threw in the Tesla Model S 60.

I attempted to pull data from manufacturer sources whenever possible. The most questionable data is the 0-30 and 0-60 acceleration times, which can vary significantly based on source and methods. I also estimated frontal area for the cars based generally on width and height. The frontal area multiplied by the coefficient of drag yields the drag area, which can be a surrogate for high speed efficiency.

There are a few holes in the table, and likely a few errors as well. I'd appreciate any corrections and if I left out a key discriminator of interest among these cars.


Enjoy!
 

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I think what's most interesting here is the question of capability, but not just any kind of capability, what are the capabilities most relevant to you and your needs?

Size wise we see crossover between the Volt, the Kia and the VW to a degree

but then cost wise its undercut by both the Ford and the VW however both of those offer less than half the Bolt's projected range.

The conclusion I'm quickly coming to is that the Bolt is likely to be the best jack of all trades. Not the fastest, not the cheapest, maybe not even with the best range. But I think what we'll see is the Chevy brand and the Chevy network combine with its competitive pricing and competitive range and competitive size to produce one of the best if not THE BEST all around package available.

Of course much of this could change once Nissan shows their next Gen leaf which is ostensibly supposed to bring similar specs to the table. But for now I don't see who's going to really encroach on the Bolt...
 

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Range was one of the main concerns that potential electric car owners were worried about and the Bolt EV answers that concern. In terms of range, only Tesla is it's competitor but the Bolt is by far the more affordable model of the three.

For me, the Bolt EV wins hands down unless Nissan can double the Leaf's range.
 

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Discussion Starter #5 (Edited)
Car & Driver just posted the Bolt EV's drag coefficient and frontal area, so I updated that and a few other things in the table. Since this forum doesn't allow editing posts after a few hours, here's the new table:

Maybe a forum admin can swap out the table link in the original thread post for this one? http://i.imgur.com/iMCyr7U.png

Anyway, if these drag area estimates are correct, it's interesting to note that the Bolt EV drag area is not low compared to the others. Only the Soul EV is worse. This implies that the highway efficiency will be less than the others. Comparing the Bolt EV to the Model S 60, the Bolt EV drag area is about 29% worse than the Model S. But the Model S weight is about 25% higher.

The EPA efficiency and range tests are a combination of city and highway driving. The Bolt EV will have an advantage verses the Model S in the city (lower weight), but will be at a disadvantage at high speed (higher drag area). If those effects cancel out, the Bolt EV would have a similar range to the Model S 60. That car has a 208 mi range, which is in-line with what GM has promised for the Bolt EV.

If you're interested in learning more about drag and cars, I recommend reading Drag Queens: Aerodynamics Compared.
 

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that's slightly disappointing, but I would imagine it's a penalty for being a hatchback. Which kinda makes you wonder why GM went with a hatch instead of a sedan...
 

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Discussion Starter #7
that's slightly disappointing, but I would imagine it's a penalty for being a hatchback. Which kinda makes you wonder why GM went with a hatch instead of a sedan...
I can speculate a couple of reasons why the Bolt is a tall wagon/hatchback:
- Avoid more direct competition with Volt
- Higher seating positions are desired
- A BEV already compromises range and flexibility and so the additional interior space helps to compensate
- It helps highlight the packaging efficiency of the flat floor and dedicated platform

But just to be clear, ALL the cars on the list are 5-door hatchbacks, including the Model S. Some are more "liftback", like the Volt and Model S. Some have more vertical 5th doors like a traditional wagon, such as the Bolt EV and Soul EV. It's the base drag from that abrupt end that hurts the Cd number.

Another point of reference is the Cd for the Tesla Model X, a CUV with a slanted rear door, which is 0.24.
 

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To be fair, these are claimed drag coefficients. Car and Driver testing got 0.32 for the Leaf, for example. Even the C&D testing can't necessarily be relied upon. I'm also not sure where C&D got 0.312 from for the Bolt. I haven't seen it published by anyone else.


Really what matters is efficency. When the Bolt's EPA efficiency numbers come out late this year we'll be able to get a better handle on how efficient it is compared to these other cars.
 

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Discussion Starter #10
To be fair, these are claimed drag coefficients. Car and Driver testing got 0.32 for the Leaf, for example. Even the C&D testing can't necessarily be relied upon. I'm also not sure where C&D got 0.312 from for the Bolt. I haven't seen it published by anyone else.


Really what matters is efficency. When the Bolt's EPA efficiency numbers come out late this year we'll be able to get a better handle on how efficient it is compared to these other cars.
Excellent point--what matters is what's experienced on the road and even the EPA numbers are only a surrogate for real world performance (reference VW).
 

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Discussion Starter #11
I updated the table again based on feedback.

Changes include:
- Added the Hyundai IONIQ BEV; not much is known about it but it should hit the market this fall.
- Added info on cabin heating technology since that can significantly effect winter driving range.
- Added the "anticipated changes" row at the bottom that is more speculative
- Corrected a few errors

Link to updated table: http://i.imgur.com/GPAPkih.png

Please let me know if you see anything else that should change!
 

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The Bolt Ev will be the most efficient EV

To be fair, these are claimed drag coefficients. Car and Driver testing got 0.32 for the Leaf, for example. Even the C&D testing can't necessarily be relied upon. I'm also not sure where C&D got 0.312 from for the Bolt. I haven't seen it published by anyone else.


Really what matters is efficency. When the Bolt's EPA efficiency numbers come out late this year we'll be able to get a better handle on how efficient it is compared to these other cars.
The Spark EV is presently the most efficient EV which has reached and passed (under good conditions) 5 miles per kWh, which allowed some Spark EV owners to pass 90 miles of range for the 18 kWH capacity. The Bolt EV battery can be better than 40 kWH so its range is estimated for this same efficiency number. But the test engineers have posted several times that their "mules" have passed 200 miles of range. So I expect the Bolt EV to reach 6 miles per kWh, surpassing the Spark EV.
 

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I personally believe GM has the highest level of engineering expertise....

Styling could have been sexier like tesla does for strong sales...but from a spec sheet....in my opinion no one comes close to GM..
 

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Discussion Starter #14
The Spark EV is presently the most efficient EV which has reached and passed (under good conditions) 5 miles per kWh, which allowed some Spark EV owners to pass 90 miles of range for the 18 kWH capacity. The Bolt EV battery can be better than 40 kWH so its range is estimated for this same efficiency number. But the test engineers have posted several times that their "mules" have passed 200 miles of range. So I expect the Bolt EV to reach 6 miles per kWh, surpassing the Spark EV.
Whoa, there are a few facts that need to be clarified here.

The i3 has the highest EPA Fuel Economy rating (ever) at 124 MPGe vs the Spark EVs 119 rating. That's a reasonably good standard under which to rate the "most efficient EV". Any car can get crazy good efficiency or range under optimal conditions, which are not repeatable or even relevant.

There is no physical way for the Bolt EV to exceed the EPA Fuel Economy rating of the Spark EV. They both have the same fundamental drivetrain efficiency but the Bolt weights 25% more (bad for city efficiency) and the Bolt has 7% higher drag (bad for highway efficiency). I would be surprised if the Bolt EV EPA rating came in above 110 MPGe.

The "Efficiency" row in the table is a simple calculation of EPA range divided by battery energy. It may be misleading and so maybe I should just delete it from the next revision of the table.
 

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Discussion Starter #15

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Discussion Starter #16
Here's another update to the spec comparison. There were lots of changes including:
- Added Model 3 info known to date
- Added Smart ED, Model S 90D, Model X 90D, Fiat 500e, BMW i3 REx
- Added general categories (200 mi BEV, 100 mi BEV, Ext Range, Lux BEV)
- Reordered based on advertised range within category
- Added more EPA data, battery supplier, motor type, DC fast charging data, and automation
- Delineated optional equipment in blue text

As always, suggestions or corrections welcome.

Link to spreadsheet on OneDrive

Link to image of spreadsheet --> http://i.imgur.com/pSI9JE5.png
 

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Admittedly, i just looked at the 200-mile BEV section with just the Model 3 and Bolt EV since they are the most relevant models to me. The Model 3 does have more features including an AWD option but the wait for one is going to be brutal compared to the almost out Bolt.

Just a question, what's liquid active thermal control and tesla thermal management?
 

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Just a question, what's liquid active thermal control and tesla thermal management?
http://insideevs.com/chevy-bolt-200-mile-ev-battery-cooling-and-gearbox-details-bower/

Much of the LEAF battery degradation issue is related to their lack of thermal management. They use a completely passive system (no fans) of air cooling. Admittedly, the newer iterations of the battery pack have been much better, but if I were to own an EV (vs lease) it would certainly have active thermal management. Flat out truth - Heat kills batteries. (Hence the caution many manufacturers make against too frequent Quick Charging)
 

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Thanks for the spreadsheet Zoomit! All the models are so organized and easy to compare on the chart.

I noticed that most of the electric cars have a small tires than the Tesla models. From what I can understand, smaller tires are supposed to be more fuel efficient, guess Tesla is confident enough in their battery range to not need the little things that increase range.
 

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Discussion Starter #20
Good observation. The tire size choices that Tesla made for the Model S and X are not the most efficient possible. The large Model 3 tire size shown is likely a performance option that also uses a larger battery. I'm sure the base Model 3 will have smaller tires, but still it's very possible they will be larger than those on other similarly-sized BEVs. Those tires are less compromising to the vehicle's handling and performance, at the expense of rolling efficiency and a slight hit to aerodynamic drag.

I would not say that Tesla is more confident in their battery range than other manufacturers. All manufacturers have very well developed analysis tools that predict their vehicle's performance and can assess different engineering solutions. The Tesla development team just came to a difference conclusion than the other manufacturers when considering their tire choices.

Generally, the Tesla engineering trades and design decisions have a notably different flavor than the other EV manufacturers. They are forced to be less conservative because they are always in a "make or break" scenario as a company. Their decision to create and fund Superchargers, their use of much larger batteries, and their targeting of luxury vehicle purchasers are examples of their long reach that more established manufacturers, for a variety of reasons, were not willing, able, or required to attempt.
 
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