[ExI] Electric cars too heavy for old UK multi-storey car parks

spike at rainier66.com spike at rainier66.com
Tue Dec 20 04:19:06 UTC 2022



-----Original Message-----
From: extropy-chat <extropy-chat-bounces at lists.extropy.org> On Behalf Of BillK via extropy-chat
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>>...Weight of electric vehicles could cause ‘catastrophic’ damage and ‘lead to car parks collapsing’

18 Dec 2022

https://publicnewstime.com/banking/weight-of-electric-vehicles-could-cause-catastrophic-damage-and-lead-to-car-parks-collapsing/

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>>...But Mr Whapples said that the accumulating risks to infrastructure like car parks and bridges remain unacknowledged.
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>...Oops!

>...BillK

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BillK, it has never escaped my notice that ExIchat seems to be nearly devoid of car guys.  I feel so lonely!  In the interest of making me less self-conscious, fearing I bore my readers, if one has no interest in cars, please stop reading here, have a nice day.

Hey, you're not a car guy!  Stop reading!

OK for BillK or anyone else with a modicum of interest in cars, you perhaps already know what a lot of the car magazines said about Tesla.  I don't mean Consumer Reports, I mean actual car hobbyist groups and magazines.  If you hang out ever with that crowd, you already know the prevailing opinion on the heavy super-powerful trendy spendy high-endy cars such as the 12 cylinder 7 series Beemers: nice cars, but the extra four cylinders are not really justifiable.  They add a lot of cost and a lot of weight, which makes them handle poorly on a tight track analogous to city streets and autocross.  Those 12ers are great on the Autobahn, or the open freeway, but on a small track such as autocross, the 8 cylinder 5 series Beemers prevail over their costly Bond James Bond 12 cylinder brethren.

Suppose we recognize what the car guys already knew: heavier more powerful cars have their advantages in some rare cases, but light is good in cars.  Now carry that lesson over to the high performance long range Teslas.  Those rigs are really heavy.  Never mind parking structures for now, just think about handling on a small track, the street or autocross racing.  The Teslas have similar drawbacks to the 7 series Beemers: they are too heavy and have two additional problems: the moment of inertia about the vertical axis is too high and the weight distribution just is all wrong.

My apologies for all this to any Tesla model X drivers, for the above is all my own humble opinion rather than any canonized collective wisdom.

The Tesla, particularly the high end ones, are heavy, which means they eat tires and get beaten on the autocross track.  But furthermore... there is something about those rigs that have always bothered me.  A gasoline engine reaches its peak efficiency at high RPM, but of course when you spin up your motor you are going fast, and the wind resistance increases as the square of the velocity.  So the increased efficiency at converting fuel to power increases but you use up the difference pushing air out of the way.

The high end Beemers with 12 cylinders are great at going really fast, but compare to the high-end Tesla.  It can do it of course, but what if you do?  An electric motor reaches its maximum efficiency at very low speed.  Batteries are most efficient at low drain rates.  So if you get your model X really cooking on the open freeway, the motors drop in efficiency, the batteries heat up and discharge less efficiently, you use up a lot of energy pushing air out of the way, and the result is that your range drops waaaay down, defeating the advantage of having a really fast car.  You get to hurry up and get in line at the charging station.  You look up to the freeway, where the granny putters by in her 37 dollar Corolla whose doors you blew off a few miles back.  She is beeping her horn to get your attention, waving and laughing derisively, as her piddly little four cylinder dinosaur burner just goes and goes and goes, like a little wind up toy that never seems to run down.  All this while you wait in line to charge your 100k Muskmobile.

Moral to the story: if one is a car guy, and completely ignores the cool factor that goes with the high end stuff, the model X and such, then the electric cars just aren't there yet.  The non-Muskovite electrics have no coolness factor, Elon has managed to alienate his own base market, and the car guys just can't get any real enthusiasm for them, analogous to how the car guys were tepid toward the 7 series Beemers.

My apologies X-drivers.  Contrary opinions welcome.  Do include a warning in the first lines for non-car people.

spike  




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