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comment by kleinbl00
kleinbl00  ·  1279 days ago  ·  link  ·    ·  parent  ·  post: GMC Hummer EV

simulated vehicle shown

The fundamental difference between electric cars and internal combustion cars is that there's a limit as to how quickly potential energy can be turned into kinetic energy when your translation is chemical. When your translation is electrical you can dump it. I helped maintain an electric RX-7 back in the '90s that could put a 4-hour charge from 1500lbs of batteries into 1/4 mile of road in 13 seconds. If you could do that with super unleaded you could fuckin' orbit a VW Golf. A Tesla Model S has a 400 mile range, and carries the energy equivalent of four gallons. Ludicrous Mode is roughly the gasoline energy equivalent of three or four of these:

What's that? You want to empty the batteries faster than the tires can connect to the tarmac? No sweat, chief it's all in the VFDs. Electric motors make peak torque at 0 RPM so what you're asking for is actually what they do best. The dirty secret of cars is that just goin' down the road they don't use that much power, and the power they do use is all about the rolling and wind resistance. This is really evident when you get them up to a reasonable speed and try to coast. My Dodge Stealth, which pretended to be a fast car, would go from 80mph to 30mph in about a thousand yards. My 911, which is a fast car, goes from 90mph (because I always overshoot by an embarrassing amount) to 80mph in the same distance.

And here's my problem with all these electric trucks, which nobody is talking about: the difference between pushing a truck through the air and pushing a Model S through the air is the difference between lofting a kite on a string and lofting a shuttlecock in the same breeze. There's just so much more wind resistance it's barely worth talking about. Never mind the tires: if you wanna minimize rolling resistance you go with the hardest rubber you can find with the least amount of tread. It's just not how truck tires are built. All that noise you hear when a brodozer braps by you on the freeway, demonstrating his freedoms? Yeah that takes energy to produce. a lot of energy. Get that brodozer up to 90 and let it coast and it might not even make it a thousand yards.

So when they say this:

Can go 300 miles on 35" Wranglers I'm... skeptical. And the first guy who cuts his mileage in half when he slaps KC lights on that thing is going to poison their marketshare forever the minute he hits "return" on a PHPbb.

I also helped maintain an electric land rover with 35" bias plys. Just driving that fucker up a hill cut the range from 20 miles to 5. It had the same battery pack and motor as the Ford Taurus we measured at a 150 mile range.





veen  ·  1278 days ago  ·  link  ·  

It's dumb, top to bottom. We now have the ability to make hoghly efficient low-footprint vehicles that are much cheaper to operate...but instead we'll probably waste the efficiency gains on big, bulky luxury SUVs with poor sightlines.

A regular hatchback with batteries in them (VW eGolf, Audi e-Tron) uses twice as much energy per mile as as an aerodinamically optimized vehicle like a Tesla or even a Renault Zoe. I can't imagine the abysmal energy per distance rate this thing will slurp.

That said: Hummers have always been petrol-slurping monsters, so I doubt it'll put anyone off from buying one to drive to football practice. Will be fun to see stranded Hummers on highways though.