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Amazon orders 100K electric delivery trucks from Rivian

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Re: Amazon orders 100K electric delivery trucks from Rivian

#201

Post by fallous »

eeZah7Ux wrote: post #138
fallous wrote: post #79

Earlier quoted context omitted.

Indeed. That does not, however, impact the actual energy available in a gallon of gasoline. Technically the 6kWh of energy spent on refining (or any other work) is itself subject to inefficiencies in generation, transmission, etc. It would also suffer from inefficiencies in the electrical storage and motive portions of an electric vehicle as well. And at the end of the day even if there were perfect 100% conversion i…

That is incorrect. You have to compare the 6kWh where it is used (at the refinery) and the 10kWh available on the vehicle. Both numbers already include the inefficiencies and therefore are comparable. Which gives to a mere 4Wh of additional power extracted from gasoline.

A "mere 4kWh of additional power" is 67% additional power.

Re: Amazon orders 100K electric delivery trucks from Rivian

#202

Post by leesec »

cloudwalking wrote: post #132
gpm wrote: post #107

Earlier quoted context omitted.

I'm not sure making a single vehicle is harder to build than a large scale plant is... but I did find this via a quick google search: https://www.rivianforums.com/threads/preproduction-rivian-r1... I wouldn't assume it's not a submarine commercial though...

Building a prototype is the easy (and fun) part. Scaling production is much harder. https://www.businessinsider.com/elon-musk-says-building-fact...

I think this is true if the prototype is known to be possible. It's not in the case.

Re: Amazon orders 100K electric delivery trucks from Rivian

#203

Post by fallous »

qqqwerty wrote: post #126
fallous wrote: post #79

Earlier quoted context omitted.

Indeed. That does not, however, impact the actual energy available in a gallon of gasoline. Technically the 6kWh of energy spent on refining (or any other work) is itself subject to inefficiencies in generation, transmission, etc. It would also suffer from inefficiencies in the electrical storage and motive portions of an electric vehicle as well. And at the end of the day even if there were perfect 100% conversion i…

I think the point is that the energy inputs required to produce a gallon of gasoline could approximately power an EV vehicle roughly the same distance that a typical ICE could go on a gallon of gasoline. A quick google search seems to back that up.

I'm not sure I'm seeing the same comparisons that you are regarding travel distances. A Tesla Model 3 uses 24-29 kWh/100 miles (depends on drive/battery options) which would be 4-5 gallons of gasoline. That would be 20-25MPG assuming the 10kWh/gallon ICE which is pretty low for a mid-sized sedan. An Accord hybrid pulls around 48MPG, while a Dodge Charger Hellcat SRT manages an EPA combined 23MPG (hardly a typical ICE given that it puts out 707 horsepower).

Re: Amazon orders 100K electric delivery trucks from Rivian

#204

Post by foobarian »

magduf wrote: post #120
danhak wrote: post #69

Earlier quoted context omitted.

The typical internal combustion engine is only ~30% efficient, getting only ~10 kWh of energy out of that gallon.

That's true, but it does ignore the waste heat, which in winter months is used to warm the passenger compartment. It's one thing EVs do have working against them, though it doesn't make up for the huge efficiency gain EVs have overall.

I know several coworkers who prefer to drive their EV in the winter because it heats up quicker (waiting ~5 minutes for the ICE to warm up the car vs. an active electric heater that starts right away)

Re: Amazon orders 100K electric delivery trucks from Rivian

#205

Post by Gibbon1 »

Retric wrote: post #192
Gibbon1 wrote: post #162

Earlier quoted context omitted.

Maybe five years ago I observed that Nissan and Tesla were homing in on the same market from opposite directions. Tesla built the Roadster which is a toy. Then the Luxo Model X and S Sedans followed by the affordable Model 3. Nissan built the affordable but limited range Leaf and just kept increasing the range every other year or so. They basically started each with one type of suck (Tesla=Price, Nissan=Range) and wo…

Oddly the leaf sales peek in 2014 then heavily fall back. http://carsalesbase.com/us-car-sales-data/nissan/nissan-leaf... So, I am not sure if they are actually moving the right direction vs introducing new car with better specks and keeping the leaf as cheap as possible. PS: I am guessing a reverse halo effect is going on.

It'll be interesting. Leaf have a not good rep vs battery life. Probably because of poor thermal management and a smaller (more highly stressed) battery pack. And short range.

But interesting to see what happens with the Leaf Plus over the next couple of years. (200 mile range more power).

Re: Amazon orders 100K electric delivery trucks from Rivian

#206

Post by eclipxe »

perardi wrote: post #137
trenning wrote: post #104

Earlier quoted context omitted.

Some friends used to make an annual trip down there. It was where the DSMs were built so it was a fun drive down in our loud rattleboxes. Neat they're using the plant again.

Oh man, the old turbo Eclipse. Now that was a car. https://en.wikipedia.org/wiki/Mitsubishi_Eclipse They don't build them like they used to. Probably for a reason. My dad heard gossip at the plant they had to move away from the racer boy turbo platform because they were just too astronomically expensive to insure–because they were invariably driven by 20-something guys who wrapped them around trees. And as an adult m…

Loved my GSX.

Re: Amazon orders 100K electric delivery trucks from Rivian

#207

Post by larrywright »

fardin1368 wrote: post #185
larrywright wrote: post #84

Earlier quoted context omitted.

Wow, I would not have expected to find so many Normalites here.

Spent 7 years in Urbana-Champaign. 45 minutes from Normal. There is huuuge potential in that area.

I’ve spent a lot of time there - agreed.

Re: Amazon orders 100K electric delivery trucks from Rivian

#209

Post by davidgould »

dzhiurgis wrote: post #171
cloudwalking wrote: post #129

Earlier quoted context omitted.

EV acceleration is directly proportional to how much current you can pull out of the battery pack, which is directly proportional to the number of battery cells, which is directly proportional to overall range... On paper, yes those numbers are feasible.

Wrong. Acceleration is driven by voltage, current dictates top speed.

This is exactly backwards.

Re: Amazon orders 100K electric delivery trucks from Rivian

#210

Post by danans »

andrewmunsell wrote: post #96
danans wrote: post #37

Earlier quoted context omitted.

It's already easier with a plugin hybrid. You can drive electric for a huge amount of the typical 20 mile daily commute, and rarely having to visit the gas station, with most of your miles being powered by the grid. If you're interested in that route, there are a ton of used Chevy Volts on the market now for $15-20k. And PHEVs are great for people in areas without good public charging infra, or who can't afford the c…

I have an i3 REx right now (also super cheap for older models), which is basically a BEV with a backup generator that powers the battery (not the wheels, like a typical hybrid or PHEV). I am on electricity 99.9% of the time for any commuting or local drives, but it enables me to do trips of practically any length which is great for me. It's a good stepping stone and my next car will be a pure BEV, but the convenience…

How do you find the performance of the i3 Rex in range extender mode?
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