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by virgo_eye 1947 days ago
It is true that the design of ICE vehicles is not arbitrary, but depends on weight/power/size/speed tradeoffs. However, there's no reason that these tradeoffs should be the same for EVs.

Drivers in city traffic can't go fast, but they like to accelerate quickly. This means a big engine, which means a big car, which means more weight so the engine has to be even bigger to keep the car accelerating 0-30 quickly.

For EVs, the relationship between battery weight and acceleration isn't the same. A new tradeoff is now between batteries which store power for a lot of driving, versus batteries which release a lot of power quickly, to accelerate sharply. There's no reason there shouldn't be a new sweet spot of very light weird-looking cars which are only driven around cities, need to be charged a lot (but who cares if not making long journeys) but have good 'driving performance'.

2 comments

I for one believe that the weight/power/size/speed tradeoffs have a lot more to do with:

- the need to have place for kids with safety seats in the back

- the need to have place for a stroller/a snowboard/a few suitcases/something else in the trunk

- the need to use the car to travel at highway speeds and dynamics at least occasionally.

I don't see any of this being changed by having an EV. Even as a second car. Especially the last point.

Some of that last point will be based on how you define "occasionally". If it's a once a year trip down a highway (for a vacation, for instance), you can make the intentional trade-off in your planning to use a short term rental or other mode of travel (plane, train) for that once a year trip to save the cost/wear/tear on your "primary" vehicle [1].

Sure, a lot of American cities in particular are not built very conveniently and often have lots of "necessary" trips on/across "highways" or roads that run at highway speeds that probably shouldn't if you were to intelligently (re)plan those neighborhoods. But that's a somewhat unique worst case to American (lack of) imagination and decades of profit-motivated dismantling of public transit options.

[1] Most accountants and engineers will even suggest that you should already be doing that even with ICE vehicle primaries that are capable of such trips, the associated costs of wear/tear add up on a primary vehicle and it often is far more cost effective for short-term rentals.

People living in cities that have been (re)built to make them convenient like that, such as Copenhagen or Amsterdam, tend to use bicycles to get around a lot. Going from bicycles to small EVs would be a step back on pretty much any metric imaginable.
Which is a digression from most of the main discussions here. Though in lieu of that digression other threads around here also point out the usefulness of pedal-assisted e-bikes and how the same trends leading to small EVs are causing an explosion in e-bikes right now as well.
Sorry, I was not meaning to digress, I think it's very much on-point.

My point all along is that miniature EVs are a solution in need of a problem. I used to live in Oslo for some time, and the ratio between Buddy cars (Norwegian made miniature EVs) and normal-sized EVs was really small. And Buddy manufacturers went out of business. Because it goes something like this:

1. If you live downtown, you walk places, ride a bicycle, or take public transportation.

2. If you live further away, you need something that can be used as an actual car on Ring 3 around Oslo.

Miniature EVs are not a good fit for either of those groups.

Small cars make more sense in other cities. It's a digression because the thread above is more on why they couldn't work in cities where they would be beneficial overall, especially as a transition tool while (re)bootstrapping public transport. While I can mostly only speak to the American experience, obviously China is seeing some niches today, and parts of Europe that aren't quite as well adapted to biking and public transport may see them as well.

I can mostly only speak to the American suburban diaspora, and small EV cars could be an incredibly useful transition tool where scales are far too big for comfortable biking (much less walking), little to no public transportation exists, but small enough with some speed limit changes to common streets may be perfect for small EVs in theory. Which is why most of the other conversation above (and in related threads) is about the challenges in using it as a transition tech in America: that family size averages might be too big to be comfortable in small EV cars, that Americans have grown accustomed to cars being the only generally available means of transport whatsoever between destinations, that Americans heavily rely on primary vehicles for long tail secondary functions (hauling, cargo, long distance trips), and that the American "dream" is entangled with this notion that one's primary car should be able to serve every part of that long tail of rare/unusual secondary functions, and that every American is indeed trapped in the tragedy of commons that vehicles "must" get larger and deadlier to feel "safer" and "more in control".

It would be wonderful if America were able to rebuild cities to be more like Amsterdam/Copenhagen/Oslo magically overnight so that biking and public transportation would serve most uses. It's just unlikely to happen magically, much less overnight, and small cars could be a convenient transition tool to bootstrap something better. (But probably won't be given current American sociopolitics.)

A capacitor (or two batteries) would improve acceleration performance without the need for as much of a trade-off.