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Rivian R2: Electric Mid-Size SUV

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Re: Rivian R2: Electric Mid-Size SUV

#321

Post by ponector »

alberto467 wrote: post #261
bobchadwick wrote: post #260

Earlier quoted context omitted.

Modern cars aren't built as well. Can you cite a source for this? There's no question that they're vastly more complex, but I would think that modern car manufacturing is far more exacting (and efficient) than in the past. If you're saying that older cars are more repairable, I'm happy to agree with you, even without a source to back up that claim.

Efficient manufacturing means exactly building stuff as cheaply as you can get away with. There's a reason why roman architecture is still standing: it is massively overbuilt, the very opposite of efficient (they also used to make the architect stand under his own arches as they removed the temporary support, that could have contributed to the overbuilding).

>> roman architecture is still standing

Is it? Every city in Roman empire had temples and forum. Where are they still standing? Maybe half a dozen survived, like pantheon in Rome or temple in Nimes, but it's extremely rare. Maybe they weren't overbuilt at all?

Re: Rivian R2: Electric Mid-Size SUV

#322

Post by r00fus »

baumy wrote: post #100
dalyons wrote: post #80

Earlier quoted context omitted.

The RAV4 EV capacity is so small, the electric engine so weak (cuts to gas well before highway speed), and the charge speed so slow, that in practice its a 100% gas car. Only a small number of disciplined owners are going to be able to run it as an EV most of the time, as its actually impractical to do so. It’s a gas car, with greenwashing.

This is completely false. I own one. It goes up to the low 80s mph before the gas engine kicks in. Acceleration from a stop is sub 6 second 0-60. Hardly weak. Charges from fully empty to full in about 2.5 hours. Mine gets a 40-45 mile all electric range. I drive 10-12k miles per year, and ignoring extended multi-day vacation road trips once every couple years, I fill up the tank 2-3 times per year.

I rented a BYD M9 PHEV minivan while on vacation in Cancun, Mexico and other than the vehicle winning over my family in, like 2 days, the mileage was amazing. 1000km range, of which, 180km was battery (that's 520mi of gas + 100mi battery range).

PHEVs in the US are gimped by poor regulatory incentives - we should be forcing manufacturers to increase overall range + EV range. If this model were sold in the US by a US manufacturer, I bet the ranges would be halved (and still considered good/decent in comparison to existing alternatives).

Re: Rivian R2: Electric Mid-Size SUV

#323

Post by kn0where »

jebarker wrote: post #267
JeremyNT wrote: post #258

Still a massive vehicle! Bulky electric cars make so little sense, because then you need bigger batteries, which... further increase the weight. The upcoming R3/R3x is likely to be a way more practical vehicle for most people, unless you have a large family to haul around. [0] [0] https://www.caranddriver.com/rivian/r3

AIUI this might not be as bigger problem as you’d imagine. Aerodynamics dominate most of the resistance at medium to highway speeds. This was discussed in the recent Rivian R1T cannonball run conversion videos where they doubled the battery capacity (and therefore drastically increased the weight of the vehicle) without substantially affecting efficiency.

Yes, weight alone is not that important for fuel economy at highway speeds. Aerodynamic efficiency of a vehicle is determined by the cross section area + drag coefficient. A 90s Honda Civic has a worse drag coefficient but a vastly smaller cross section than the Rivian, so it needs to move less air out of the way to drive forward. Smaller EVs can go farther with smaller batteries, but the American consumer has decided for one reason or another that cars must be tall, and therefore less aerodynamically efficient.

Re: Rivian R2: Electric Mid-Size SUV

#324

Post by wpm »

1970-01-01 wrote: post #290
wpm wrote: post #283

Earlier quoted context omitted.

Uhhh, what? No it isn't. Having a sharp knife is safer than a dull one. Having a massive heavy steel box that weighs thousands of kilos that can accelerate that quick, that you can operate in public with little to no useful training is not safer. I'm sorry, no car outside of a race track needs to accelerate that quick. It's absurd.

The analogy fits perfectly. A slow car is also unsafe, that's why low speed plates exist along with minimum speed limits. There's no such thing as a vehicle with too much acceleration and never will be.

Yeah what qualifies as a "slow car"? An Amish dude on a horse and buggy?

I have driven plenty of "slow" cars with less than 100 horsepower without issue. If you can't figure out how to merge that's a skill issue, another prime reason not to be giving people cars with former F1 car levels of acceleration. You don't need 0-60 in 3 seconds to fucking merge, get real!

Re: Rivian R2: Electric Mid-Size SUV

#325

Post by [deleted] »

darth_avocado wrote: post #306
consumer451 wrote: post #301

Earlier quoted context omitted.

New base Nissan Leaf is ~30k after delivery fee, and looks pretty darn great.

I’m not sure if you’re agreeing to what I said or if this is meant as a counterpoint. But that’s kind of proving my point, new cars are pretty expensive these days. If you’re getting a base Nissan Leaf for $30k, SUVs costing $45k don’t sound that unreasonable.

[deleted]

Re: Rivian R2: Electric Mid-Size SUV

#326

Post by nomel »

actionfromafar wrote: post #236
nomel wrote: post #182

Earlier quoted context omitted.

How much of that performance comes for free, from optimizing for range/efficiency? What's the obvious "that could be less" in the system that wouldn't negatively impact efficiency?

None of it. It the motor is smaller, it pulls less current. If it pull less current, you can use batteries which aren't specced for high amps. If use use less amps, you can use thinner cabling and split the batteries up i various compartments. That means heat is more distributed. Less active cooling, if any, is needed, of both batteries and motors. All of the above can translate to less weight, which mean better rang…

> from optimizing for range/efficiency?

I meant for normal highway driving, not drag racing.

Optimal highway driving is still lowest resistance and losses. Cold weather driving is what mostly results in a battery capable of the high performance, from what I understand.

Is a "small" motors more efficient than a large one? I suspect no, with the assumption that everything is sized so the "drag race" operating range would be well into the peak, rather than sustained, operating range.

Re: Rivian R2: Electric Mid-Size SUV

#327

Post by plugger »

wilg wrote: post #99
plugger wrote: post #94

I feel quite bad for people living in the United States. Despite the constant refrain about freedom y'all are actually pretty hindered when it comes to reasonably priced EVs. On Saturday I put a down on a BYD Shark 6 truck. Hopefully I'll collect it Friday, if not early next week. I'm paying $41,200 USD for the thing brand new. I saw a MotorTrend review of it last week, they flew down to Mexico City to test one out.…

A BYD Shark 6 is not an EV?

It's a HEV, not a BEV. But it's an EV none the less. It has the ability to drive ~100km on battery only, and the engine doesn't drive the wheels, it's used to recharge the battery.

Re: Rivian R2: Electric Mid-Size SUV

#328

Post by plugger »

sgt wrote: post #133
plugger wrote: post #94

I feel quite bad for people living in the United States. Despite the constant refrain about freedom y'all are actually pretty hindered when it comes to reasonably priced EVs. On Saturday I put a down on a BYD Shark 6 truck. Hopefully I'll collect it Friday, if not early next week. I'm paying $41,200 USD for the thing brand new. I saw a MotorTrend review of it last week, they flew down to Mexico City to test one out.…

If it's going to have a gasoline engine anyway, I'd much rather just get the Raptor. By the way, the Ford Ranger Raptor is not to be confused with the Ford F-150 Raptor which is a total beast.

It's the best of both worlds as you can drive it EV only for short distances but still have the ability to drive longer distances. As said above, the engine is only to charge the battery.

Re: Rivian R2: Electric Mid-Size SUV

#329

Post by nomel »

mortos wrote: post #276
actionfromafar wrote: post #236

Earlier quoted context omitted.

None of it. It the motor is smaller, it pulls less current. If it pull less current, you can use batteries which aren't specced for high amps. If use use less amps, you can use thinner cabling and split the batteries up i various compartments. That means heat is more distributed. Less active cooling, if any, is needed, of both batteries and motors. All of the above can translate to less weight, which mean better rang…

Weight has nearly no effect on range of an EV. The YouTube channel Aging Wheels has two good videos on this. Here he talks about towing, and he demonstrates loading the truck to max capacity makes nearly no difference: https://youtu.be/UmKf8smvGsA He also covered an attempted Cannonball run where they stuffed two extra battery packs into a Rivian R1T: https://youtu.be/yfgkh4Fgw98 Real differences makers are smaller w…

> are smaller wheels

Looks like rolling resistance decreases with diameter [1]. So, is it from the increased drag from higher stance? Would lowering the car the same work better?

[1] https://www.tirereview.com/science-behind-rolling-resistance...

Re: Rivian R2: Electric Mid-Size SUV

#330

Post by dgently7 »

AH4oFVbPT4f8 wrote: post #305
gorgoiler wrote: post #153

I bought a new salad spinner recently, after having broken yet another one. I’ve had fancy brands like Zyliss and OXO. I’ve had cheap store brand models and cheaper Amazon MYSSNGVWL type stuff as well. Knowing they would probably break didn’t make it feel better when they eventually broke. Anyway the new salad spinner is large, heavy, with a steel pin into a brass bushing, has a metal handle and nylon gears in a seal…

While I can't help you with a car, I share your desire of wanting things with replaceable parts, so I leave you with this, the coffee maker version your salad spinner, https://us.moccamaster.com . All parts replaceable.

espresso machines are maybe in a different class of "coffee maker" but it seems like even the cheapest of those is pretty easy to service/repair/source parts.

or in some cases even upgrade to improve capabilities...

I did the gaggiauino mod to my gaggia classic and basically everything in there is just pipes and wires... the most complicated single part on the original is the vibratory pump. I'm pretty sure i could keep that same machine going indefinitely with access to parts.

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