Article

2023-04-13 -Signs, Portents, and the Weather-

Elon's Terrible, Horrible, No Good, Very Bad Battery Math

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Posted by M. Murcek 2023-04-13 00:00|| || Front Page|| [11135 views ] Top

#1 Cried a City Hall clerk from Nahant,
"Buy a house and a car? Why, you can't!
Por favor, don't be pissed --
For mordida, I list
You to share an electric Trabant."

Posted by Spereting Cleregum7438 2023-04-13 00:41|| 2023-04-13 00:41|| Front Page Top

#2 There has never been such a measurable depth of scientific illiteracy and basic innumeracy...

Now, everybody counts. /pun

Posted by Skidmark 2023-04-13 08:08|| 2023-04-13 08:08|| Front Page Top

#3 Also left out of the calculations is a thing called "transform efficiency", which is basically, every time you store, transform, transmit, or use energy there is a loss. Always more than 20%, sometimes north of 80%. You can't get as much power out of a battery as you put into it; you can't get as much out of a transformer as you put in.
You notice how these things get warm in use? That heat is the power that's being lost in the transform.
It's called thermodynamics. And there's no getting away from it. (It's why they keep trying to develop superconductors.)

Posted by ed in texas 2023-04-13 13:57|| 2023-04-13 13:57|| Front Page Top

#4 Someone did a fantastic layman's summary of the laws of thermodynamics:

You can't win.
You can't break even.
You can't get out of the game.

Posted by M. Murcek 2023-04-13 13:59|| 2023-04-13 13:59|| Front Page Top

#5 Projecting the future based on current tech is a fools shell game.
Musk may find a way to produce far more out of his gigafactories, or they may find the original numbers they were hoping to reach were in reality far lower than they thought.

Posted by ruprecht 2023-04-13 16:45|| 2023-04-13 16:45|| Front Page Top

#6 My personal theory, based on no evidence whatsoever, is that Elon cares fookall about batteries here on earth. He is going to Mars and to do that he needs rockets, autonomous vehicles and batteries. Hence, his investment in these technologies.

Posted by SteveS 2023-04-13 17:46|| 2023-04-13 17:46|| Front Page Top

#7 That is a really good theory but it has one flaw. The autonomous vehicles part. Musk has insisted on using visual systems for his autonomous Teslas instead of Lider which would seem much better for outer space usage. Maybe there is something about visual that makes it better on Mars with the dust and all, if so I can't see it.

Posted by ruprecht 2023-04-13 21:29|| 2023-04-13 21:29|| Front Page Top

#8 An interesting point, ruprecht. I did not know this, but apparently Tesla has dropped both ultrasonic and radar sensors, and gone all in on optical methods. Welcome to Tesla Vision!

Lidar gives you a nice clean 3D point cloud but starts to fall down in dusty or rainy environments. Optical methods and computer vision tricks can use information like color for object discrimination and tracking.

If I were me, I'd be trying some sensor fusion from both lidar and visual. But maybe Elon tried that already.

Posted by SteveS 2023-04-13 23:29|| 2023-04-13 23:29|| Front Page Top

23:29 SteveS
23:06 JohnQC
22:53 Injun McGurque7571
22:16 Helmuth, Speaking for Sholugum4538
22:11 Injun McGurque7571
21:59 DooDahMan
21:57 DooDahMan
21:44 DarthVader
21:29 ruprecht
21:09 Frank G
19:56 Airandee
19:54 Rex Mundi
19:48 Frank G
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19:04 M. Murcek
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18:57 irish rage boy
18:32 SteveS
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17:46 SteveS
17:36 Rex Mundi
17:35 Skidmark