Nonsense from John Petersen

[winfield100]

Challenge everything he says

he seemed to take a bit of offense when I thanked him for being an indicator
It seemed to bother him when I thanked him, several times, for helping the TSLA go from around 180 to around 206 or so and givine me a nice 14% gain in a month, and thanked him again.

edit
i checked in an JP refuses to take credit or blame for TSLA SP rise.

 

[dc_h]

Challenge everything he says

Back in 2012/2023 he proved EV's were not physically practical due to energy density. Now he is proving that solar power and battery backup is not practical due to financial models. While I'd like to see mitchji and some other experts respond on cost trends, I'm happy to see him writing again. He seems to have an amazing sense of timing. If model 3 and TE run to plan in 2017 we will have to wait until 2020 to here from JP when he explains that Tesla can't ramp past 1 million cars due to some constraint of physics.
Merry xmas John Peterson, keep writing and sharing. We Tesla bulls owe you a Christmas and New Years pie.

 

[Dan5]

Petersen is back, this time bashing the Tesla truck idea.

He gets alot of things wrong again. 6 kwhr used to power a truck, yes, while true, he thinks a diesel engine is 100% efficient. Doesn't realize trucks don't constantly go up hill.

An average truck gets 5 mpg and the ultra efficient trucks getting 12 mpg. We have to assume Tesla would use a "super efficient truck" because less weight and batteries needed because batteries cost money.

A diesel engine has about a 45% efficiency. A gallon of diesel has about 38 kwhr of energy.

38 *.45 /12 = 1.425 kwhr per mile expended pushing the tractor trailer forward

Petersen's already off by a factor of 4.

Let's round up to 1.5 kwhr per mile for ease of math- That means for 500 miles that would require 750 kwhr (not 2.2-3.9 Mwhr)

Now let's see how much more he compounds that error

Back calculating he says each kwhr weighs 11.81 lbs per kwhr

Well, 85 kwhr pack is really the 80 kwhr effective found in a Tesla older pack weighs 8.7 lbs per kwhr

Each cell weighs 45 grams and there's 7104 of them.

So off there again.

Further, the newer cells are supposed to be twice as energy dense as the older cells, so call it 4.5 lbs per kwhr

So instead of needing 26,000 lbs to 39,000 lbs (like he says) to make a 500 mile trip

in reality it's more like 3,375 lbs- heck bump it up to 4000 lbs (using the new rumored cells).

Using the older cells around 6500 lbs

 

[jelloslug]

Petersen is back, this time bashing the Tesla truck idea.

He gets alot of things wrong again. 6 kwhr used to power a truck, yes, while true, he thinks a diesel engine is 100% efficient. Doesn't realize trucks don't constantly go up hill.

An average truck gets 5 mpg and the ultra efficient trucks getting 12 mpg. We have to assume Tesla would use a "super efficient truck" because less weight and batteries needed because batteries cost money.

A diesel engine has about a 45% efficiency. A gallon of diesel has about 38 kwhr of energy.

38 *.45 /12 = 1.425 kwhr per mile expended pushing the tractor trailer forward

Petersen's already off by a factor of 4.

Let's round up to 1.5 kwhr per mile for ease of math- That means for 500 miles that would require 750 kwhr (not 2.2-3.9 Mwhr)

Now let's see how much more he compounds that error

Back calculating he says each kwhr weighs 11.81 lbs per kwhr

Well, 85 kwhr pack is really the 80 kwhr effective found in a Tesla older pack weighs 8.7 lbs per kwhr

Each cell weighs 45 grams and there's 7104 of them.

So off there again.

Further, the newer cells are supposed to be twice as energy dense as the older cells, so call it 4.5 lbs per kwhr

So instead of needing 26,000 lbs to 39,000 lbs (like he says) to make a 500 mile trip

in reality it's more like 3,375 lbs- heck bump it up to 4000 lbs (using the new rumored cells).

Using the older cells around 6500 lbs

Stop that nonsense. Facts can never be used when proving your opinion....

 

[JRP3]

Further, the newer cells are supposed to be twice as energy dense as the older cells, so call it 4.5 lbs per kwhr

I don't think that's correct, or possible, without some dramatic chemistry breakthrough. Changing the size of the cell can will not significantly improve energy density. There could be a slight improvement from more active material vs can material.

 

[Dan5]

I don't think that's correct, or possible, without some dramatic chemistry breakthrough. Changing the size of the cell can will not significantly improve energy density. There could be a slight improvement from more active material vs can material.

Maybe I was reading something that was misreported. i remember reading something about Powerwall V2 having double the energy density of the Powerwall version 1, and Powerwall V2 is supposed to be using the new 2170 cells.

Also the 100 kwhr pack has an energy density of 8 lbs per kwhr, so they are decreasing over time (hard number from the tear down). That's why i said rumored for the doubling the density.

 

[JRP3]

The grid storage products use different chemistry than automotive. If they doubled the energy density at the cell level in automotive cells the Model 3 would could fit 150kWh instead of the claimed max of 75kWh.

 

[Electroman]

I tend to think that Petersen is right with his 2.5kWh/mile assumption.

For once I agree with his analysis

 

[Yggdrasill]

2.5 kWh/mile isn't unreasonable. I think Tesla will go with a battery pack in the 1000-kWh area, which gives a realistic range of 200-300 miles, and then either have battery swapping or really high speed chargers.

You could probably charge around 200 miles range in 30 minutes, and 2.5 hours of resting over a 1000 mile trip isn't unreasonable. That's 16.5 hours of driving at 60 mph. At least in Europe, the mandatory resting time is more than this.

 

[Oil4AsphaultOnly]

I tend to think that Petersen is right with his 2.5kWh/mile assumption.

For once I agree with his analysis

After all the work that jhm and I did with the electric transit buses and their diesel equivalent. Throw in some aero improvements, and under 2kwh/mile is more likely. 200-mile range (400-500kwh batteries) with swap stations will get the job done.

 

[Electroman]

200-mile range (400-500kwh batteries)

You got to be kidding.. You may get that in fair weather, but not in subzero temps. It is the worst case scenario that you need to be worried about..

 

[Oil4AsphaultOnly]

You got to be kidding.. You may get that in fair weather, but not in subzero temps. It is the worst case scenario that you need to be worried about..

And semi trucks aren't plugged-in and pre-heat because?

Unlike passenger cars, trucks aren't left parked for hours at a time, unless they're in a depot of some sort.

 

[Yggdrasill]

And semi trucks aren't plugged-in and pre-heat because?

Unlike passenger cars, trucks aren't left parked for hours at a time, unless they're in a depot of some sort.

Has nothing to do with heating. Heating will be completely negligible.

Air density increases by 11% between +20C and -10C. Wet roads and roads covered with snow/slush increase consumption further. And let's not talk about what happens to consumption if they put on snow chains.

 

[Electroman]

sub-zero weather will take out an additional 30% of energy, which is nothing to do with cabin heating at all.

 

[AudubonB]

One factor that will massively raise kWh consumption is the mandatory use of chains in some locations/times of year.

From my experience with heavily loaded light trucks (30,000 lb load), chaining up changes mpg by about 40 percent. I can reach out to my Class-8 connections, but I think that's a reasonable number to consider. In parts of the more mountainous portions of NoAm, a trucker can expect to keep chains on for eight hours at a time.

When on the Dalton or Dempster, etc, routes....that can be 100% of the winter run. Fun fun fun.

 

[Oil4AsphaultOnly]

One factor that will massively raise kWh consumption is the mandatory use of chains in some locations/times of year.

From my experience with heavily loaded light trucks (30,000 lb load), chaining up changes mpg by about 40 percent. I can reach out to my Class-8 connections, but I think that's a reasonable number to consider. In parts of the more mountainous portions of NoAm, a trucker can expect to keep chains on for eight hours at a time.

When on the Dalton or Dempster, etc, routes....that can be 100% of the winter run. Fun fun fun.

@yggdrasil and @mkjayakumar too. First of all, my bad. I was posting using details from another thread without linking it. Please see jhm's post to see the start of it: Shorting Oil, Hedging Tesla

In his post, NREL provided an diesel mpg rating of ~6mpg's for class 8 transport trucks. This mpg rating was from operator data so it should've included driving uphill/downhill/snow/rain, etc. The data also provided mpg ratings of transit and school buses AND electric transit buses. We went back and forth trying to use the transit bus energy consumption to extrapolate out the class 8 truck energy consumption. 1.78kwh/mi was the energy consumption of the transit bus. 2.18kwh/mi was what was calculated from some reasonable assumptions (excludes assumptions of Cd of those trucks - 0.8-0.7 implied).

The only energy consumption that isn't factored in by the nrel numbers is pack-heating, which was why I originally mentioned it.

2.5kwh/mi is a more than generous energy cost assumption for the rolling bricks that class 8 trucks were (driving the existing routes, hills, rain, snow and all). A 50% reduction in Cd would yield a 33% reduction in energy consumption. So 2kwh/mi (after aero drag reductions) seemed very reasonable.

Please try out the spreadsheet formulas to see for yourselves (not providing link since you should follow the thread to understand the context).

Edit: as for the 100% chains route, perhaps space the swap stations closer together? Since driving with chains implies a 20mph avg speed, so 100 miles will still mean 5 hrs of straight driving.

 

[Yggdrasill]

You can't use *average* consumption to determine required battery size. You need to use something closer to *worst case* consumption. Reaching the next ludicrouscharger *on average* isn't good enough. You need to be pretty damn sure you will be able to reach it.

Average consumption can however be used to calculate cost per mile or TCO.

Also, I agree that on problematic routes, you will need to space the ludicrouschargers closer together. Also important, I think that Tesla should offer multiple sized battery packs. Alternatively, something like a standard 1000 kWh pack for the truck, with an optional 500 kWh pack for the trailer. This would provide greater flexibility for more use cases.

 

[NeverFollow]

I read through the article and then saw the statement by Seeking Alpha that Peterson gets paid $0.01 per page view. Damn, I just made him a penny richer. Must remember to avoid his posts in the future.

He gets $35 and $0.01 per click

I noticed it and I was going to make the same report.

I stopped reading 'Seeking Alpha' for a long time.

The content of this Web site is just B.S. and use controversial titles as a beat.

 

[Oil4AsphaultOnly]

You can't use *average* consumption to determine required battery size. You need to use something closer to *worst case* consumption. Reaching the next ludicrouscharger *on average* isn't good enough. You need to be pretty damn sure you will be able to reach it.

Average consumption can however be used to calculate cost per mile or TCO.

Also, I agree that on problematic routes, you will need to space the ludicrouschargers closer together. Also important, I think that Tesla should offer multiple sized battery packs. Alternatively, something like a standard 1000 kWh pack for the truck, with an optional 500 kWh pack for the trailer. This would provide greater flexibility for more use cases.

I can't see ludicrouschargers being the solution, due to peak-demand charges (all commercial customers are billed like this). A 1mwh pack (using 2170 cells) would weigh over 3 tons! That would be a waste of cargo capacity for the short-haul truckers. I think stackable 100kwh packs make more sense (much like how powerwall and powerpack are composed of one or 14 battery pods), as it scales better with use-cases without needing multiple case sizes. I've fleshed out the idea here: Shorting Oil, Hedging Tesla

 

[JRP3]

Can't keep a good FUDmeister down: Tesla's First Decade Of Battery Pack Progress - Much Ado About Nothing - Tesla Motors (NASDAQ:TSLA) | Seeking Alpha

He takes the data from the EPA documents and concludes that the Model 3 battery pack density is lower than the S and therefore there is no progress in cell energy density while ignoring the fact that the Model 3 pack includes items that were placed elsewhere in the S and X. He also ignores the possibility that the EPA document could contain inaccurate data, even though there are past examples of this happening. I helpfully explain this in the comment section, we'll see how he amends his article to reflect this...