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Tesla, TSLA & the Investment World: the Perpetual Investors' Roundtable

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Huh, options volume has grown since earlier today. Anyone's guess?

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And now....

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Apparently there are some traders that are desperate to burn their cash today 😅
 
but..can you see Russia from your home?
Is it easier to get to Paxson by Audi, Tesla, or Audie's big Ford?
(4th & final verse):
That leaves the Denali Highway to Cantwell
It’s beautiful all of the way.
But they don’t plow the snow
So if to town one must go
It‘s by dogsled or skidoo or sleigh.
 
Air drag is proportional to airflow speed squared.

60 mph is more generous to the diesel truck in the Tesla Semi comparison. It’s fast enough to represent a plausible highway cruising scenario without much braking and acceleration, but slow enough that diesel’s abysmal 40% propulsion efficiency isn’t as much of a disadvantage compared to the Tesla.

(75/60)^2 = 1.56 —> 56% increase in energy loss from air friction between 60 mph and 75 mph.

With 56% more propulsive power needed, the inferior aerodynamic shape and propulsion efficiency of the diesel truck stand out more at 75 mph. With 75 mph being a much more realistic actual highway speed, this means the real-world cost advantage will be a lot better than what Tesla originally presented.

Basically, energy efficiency is the biggest operating cost advantage of the Tesla Semi and the 2017 presentation seriously downplayed this economic advantage by:
  1. Presenting the most energy-efficient realistic driving mode for any truck, which is 60 mph cruising
  2. Using $2.50/gallon diesel price
My experience with my Tesla tells a different story. My Tesla is significantly more efficient than an ICE counterpart. That's why I can go ~300 miles with 75kWh which is equivalent to only 2.2 gallons of gasoline. That's about 130 MPGe. Yet my ICE counterpart has an 18 gallon tank storing 600kWh of energy. The biggest factor in this stark contrast is that ICE are so wasteful, where ~70% of that 18 gallon tank is wasted in heat and non-motive losses. Now, when you look at the pie chart of energy usage of ICE, the biggest piece of the pie is the aforementioned ~70% out the tailpipe / heat, but another sliver of the pie is aerodynamic losses. It's, say 10% of the losses. If I drive an ICE vehicle faster, that sliver gets a little bigger. For argument sake, let's say I drove so much faster, that my aero load was +50%. On the ICE pie, it went from 10% to 15%. With the high efficiency of EVs, they don't have that ~70% pie piece and so aerodynamic load is a much larger percent of the pie. Let's say it's 30% of the EV pie...when I drive faster and increase my aero load +50%, it goes from 30% to 45%. Increased aero load impacts EV range far more than it impacts ICE range. Now, EVs are generally more aerodynamic for this very reason, but they can't overcome the significantly higher percentage of the pie that they represent. I don't think the Tesla Semi, with the required large frontal cross section, can change this calculus?

I certainly notice this when I drive 85 MPH in EV vs ICE. Help me understand how I'm missing your estimates.
 
My experience with my Tesla tells a different story. My Tesla is significantly more efficient than an ICE counterpart. That's why I can go ~300 miles with 75kWh which is equivalent to only 2.2 gallons of gasoline. That's about 130 MPGe. Yet my ICE counterpart has an 18 gallon tank storing 600kWh of energy. The biggest factor in this stark contrast is that ICE are so wasteful, where ~70% of that 18 gallon tank is wasted in heat and non-motive losses. Now, when you look at the pie chart of energy usage of ICE, the biggest piece of the pie is the aforementioned ~70% out the tailpipe / heat, but another sliver of the pie is aerodynamic losses. It's, say 10% of the losses. If I drive an ICE vehicle faster, that sliver gets a little bigger. For argument sake, let's say I drove so much faster, that my aero load was +50%. On the ICE pie, it went from 10% to 15%. With the high efficiency of EVs, they don't have that ~70% pie piece and so aerodynamic load is a much larger percent of the pie. Let's say it's 30% of the EV pie...when I drive faster and increase my aero load +50%, it goes from 30% to 45%. Increased aero load impacts EV range far more than it impacts ICE range. Now, EVs are generally more aerodynamic for this very reason, but they can't overcome the significantly higher percentage of the pie that they represent. I don't think the Tesla Semi, with the required large frontal cross section, can change this calculus?

I certainly notice this when I drive 85 MPH in EV vs ICE. Help me understand how I'm missing your estimates.
This is exactly what I was thinking. The only time a ICE semi would be able to compete is at speeds near 80mph. It’s like trying to tow with a Tesla, the increased drag at speed massively impacts range, more so than an ICE. At low speed a Tesla would get way better equivalent range towing than an ICE.