Why it's time to get over your EV range anxiety [Arstechnica]

I too don't want to drag around unnecessary weight. That is why I tossed the cigarette lighter years ago. And of course I don't keep the owner's manual in the car. Just dead weight that has no use to the 99.44% of the population that doesn't bother to open it because they know everything. Rear floor mats are another thing. I'm glad BMW stopped supplying them. Nobody sits in the back anyway. Just dead weight.

With bare feet or in this case bald tires, and no heat (a la Beetle).

 

Wait what, the much-vaunted Lucid Air is no more efficient than the much-derided SE (personally I get over 5 mi/kWh in the summer)? That's interesting. Not knocking the Air, but maybe MINI should be talking up the engineering of the SE more.

It sure would be nice if there was some comparison of all EV models by efficiency instead of just range.

 

I'm sure you'd be getting much better than the rated efficiency in the lucid but definitely pretty crazy that the MINI is 0.02mi/kWh (rated) better than the lucid even with it's rather poor ~0.3 drag coefficient! Just goes to show a major advantage of small cars, the area part of the drag equation is just as important as the drag coefficient.

Thanks to @fishbert for the site, you can sort by efficiency here:

EV database

 

It's almost like they should make more than one car since people have different use cases, budgets, priorities, and desires or something.

 

8 months of ownership with the SE and have come to the realization that an SUV is completely unnecessary for my family (me, wife, toddler, and our little chihuahua). Feel good not having to lug around extra battery for no reason.

 

So what we all learned is if you want to get maximum efficiency on the highway, you should be setting the cruise control to 31MPH (50km/h). Now you can make the one-way 150 mile MINI SE trip in 4.8 hours WITHOUT charging!! #highwayhypermiling

 

Pretty simple, correlation does not mean causation.

This study is comparing mass to energy usage. It demonstrates a correlation, not a causation. Energy use does absolutely increase with mass but it's not because of mass. Bigger things are heavier. Bigger things have more aerodynamic drag. Of course a 15mph electric kick scooter uses less energy than a car on the highway.

They added some weight to a car and found an 8% reduction in range. Adding a significant amount of weight to a chassis (and tire) not adequately designed for it could definitely increase rolling resistance. Did they even adjust the tire pressure?
Besides, their own chart shows no correlation between vehicle weight and efficiency:

This is a paper discussing a simulation published in a non-peer reviewed journal intended to be used for conferences. Not exactly credible.

"Procedia Engineering is an e-only product focusing entirely on publishing high quality conference proceedings."

"Organizers are being credited on the actual issue and are fully responsible for quality control, the review process and the content of individual conference papers."

 

Is that the EPA highway MPGe or the combined?

 

Just the rated range divided by usable battery capacity to avoid any differences in accounting for charging losses (data from here: EV Database)

 

I didn't say any of your studies showed causation, my entire point was that none of them showed causation. I said one of them just showed correlation and the other showed no correlation, with their own chart disagreeing with their conclusion. As said above by someone else, just because a study is published doesn't mean it's correct, especially when it's not peer reviewed like the 3rd one.

I completely agree that adding weight to a specific car with no other changes will increase rolling resistance but that little coefficient you just glossed over is hiding a ton of other detail and is no where near constant. Just ask all of the forum members who have changed to high performance tires and lost 15-20% of their range (quite a bit more than the 8% lost by adding 600lbs in study 2).

Please explain to me with this basic physics how multiple vehicles weighting 1000+ pounds more than the MINI can be just as efficient if weight causes such a significant increase in energy usage. Maybe you disagree but I consider real world efficiency of numerous heavy and light vehicles to be "actual evidence".

I have looked for a decent study but it seems neither of us can find one, at least one that's free. I have provided data but you seem to ignore those parts of my posts.

Lets review:

This was an observation about the original article, my source is the paper you posted. I did say 3.6 was high for a crossover/SUV and provided examples including my own data log showing just how much efficiency can vary from the on-paper rating. My original point was that the original paper overlooked many real world variables that would significantly alter their conclusion.

You pointed out that my example vehicles were heavy and assumed that's why they were inefficient so I provided data to the contrary with heavy but efficient vehicles. Providing data that conflicts with a thesis is usually how they are disproven.

I pointed out that there were some issues with the papers you were trying to use to prove your point, including the 2nd one showing a graph with no correlation between battery weight and efficiency and not even attempting to explain why. I'm sorry you took this legitimate criticism as heckling.

 

I find it amusing that there are a lot of articles gushing about the Kia EV6 GT being so fun to drive because it has a smaller battery pack. Maybe the irrational "more range is needed" mentality is waning. We SE owners already know the value of a lighter EV.

 

77.4 kWh is "smaller"?

 

Oh looks like I misread. The shorter range is due to the "more powerful" motors, not smaller battery pack. Well never mind then. It's just the opposite, the GT seems to be wasting battery to get performance instead of being lighter and more efficient like the SE.

 

Yes but the dual motors is integral to the 697V architecture as the rear motor acts as the 105kW brake regen during DCFC.

 

It’s worth noting at if you genuinely used 80% of the EPA range of the asE in a daily basis that amounts to over 32,000 miles per year. Hardly anyone in the US does that kind of mileage.
If you change it to just commuting 5 days a week at 90 miles round trip that’s over 23,000 miles per year just for commuting which again, hardly any American does.
If you halve the commute to 45 miles round trip we’re at under 12,000 miles per year for commuting use which seems more in line with a large chunk of the population given the mileage they actually put on their vehicles.
That just leaves the weekend use which yes, may require a single charge while away from home to get back on such a day trip. That seems doable if we’re sticking to metropolitan areas, not so much if you travel into the middle of nowhere today.
As for towing, not many people do, even the majority of pickup truck drivers never tow, never mind frequently.
How often are people driving long distances with kayaks (or whatever) on the roof? Given how I frequently I see such a sight on the highway away from civilization I’m going to suggest not very. Edge case.
And very long multi day road trips are incredibly rare as few people can afford the time, the reality is most fly. And if you do drive but only do it once per year get used to the idea of renting a car for that trip instead of paying for a battery (or gas) the whole year when you don’t need to.
People (myself included) make very bad emotional decisions when buying cars, fueled by dreams of lifestyles we don’t actually have which is why so many families end up with SUVs when a minivan is a much better choice. But image matters more than money…
I daily charge our Long Range Tesla to just 60% and get back home on 50%. The range just isn’t needed except for once every 3-4 weeks when I travel across the state and have to charge to get back home. I could do it in the mini but I’d have to also charge once in the way there and once in the at back. Not ideal but do-able. And beyond that I only really make use of the cars capability once or twice per year when I do a multi state road trip just because I like to do such road trips (it would make more sense to fly) but I suspect I am atypical, and with the currently available range, Tesla charging infra and speed, a 9.5hr gas trip has become 10hours. Big deal. If the trip was not practical I’d fly and still have an EV like the mini for day to day use anyway.

 

I drive with skis on the roof nearly every weekend in the winter, but I don't know how much that affects range. The place we go most often is about 160 miles, mainly back roads.

I told my FIL when he was building a giant garage last year to build in a 220v plug for EVs, but I'm not sure whether he did. If so, we could in theory drive up in something with 200 miles of range, charge while we're there, then drive back. But in reality we'll just take our gas car because it's less of a headache.