this post was submitted on 19 Jun 2024
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xkcd

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An idling gas engine may be annoyingly loud, but that's the price you pay for having WAY less torque available at a standstill.

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[–] [email protected] 18 points 5 months ago (4 children)

Googling tells me that:

  • Electric cars have 77% efficiency
  • Gas cars have 30% efficiency
  • Electric car batteries have 270 Wh/kg (converts to 0.97 MJ/kg)
  • Gasoline has 46 MJ/kg

So the math here says electric gives you (0.97 * 77%) 0.75 MJ/kg output and gas gives you (46 * 30%) 13.8 MJ/kg output. Plus, as someone else said, spent gasoline no longer weighs you down.

I like the idea of electric, and I want to see it replace gas as soon as possible, but fair is fair.

[–] [email protected] 11 points 5 months ago

Technically empty batteries weigh less than charged batteries.

Not that the difference is significant enough to tip the scale though.

[–] [email protected] 2 points 5 months ago

And let's not forget that fueling your car requires a tank, a decently sized pump and 2 minutes of your time. A quick charge will hopefully charge your battery to 80% in 30 minutes, while giving you less km and running 300kW of power through hefty cables and big transformers, consuming the amount of energy that a family house consumes in a few days.

(And yes, battery manufacturing and disposal consume enormous amount of resources)

Electric and gas have different situations in which they shine. Gas/diesel engines are just a bunch of steel and some control chips, optimized in more thana century of technological development if we couls develop carbon neutral fuel, electric cars would not be needed. Unfortunately, it woulf be difficult to do at scale of current fuel consumption. More (electric, battery-less) public transport, less road goods transportation, more nuclear, electric for vehicles that move 100% of the time (delivery and logistic vehicles) and carbon-free fuel for other kinds of vehicles (personal transportation) is a good balance, in my personal, ignorant, armchair opinion.

[–] [email protected] 0 points 5 months ago

How do you think about hydrogen cars? They have better fuel density, and hydrogen is renewable.