this post was submitted on 11 Nov 2024
1 points (100.0% liked)

solarpunk memes

6012 readers
9 users here now

For when you need a laugh!

The definition of a "meme" here is intentionally pretty loose. Images, screenshots, and the like are welcome!

But, keep it lighthearted and/or within our server's ideals.

Posts and comments that are hateful, trolling, inciting, and/or overly negative will be removed at the moderators' discretion.

Please follow all slrpnk.net rules and community guidelines

Have fun!

founded 4 years ago
MODERATORS
 

Key context: thermodynamics dictates that heat engines waste a lot of energy.

Credit: Karin Kirk

top 13 comments
sorted by: hot top controversial new old
[–] ShrimpCurler@lemmy.dbzer0.com 1 points 2 years ago (2 children)

I think the 80% number is outdated (although most of the energy is still wasted)

F1 engines achieve a peak thermal efficiency above 50 percent, significantly higher than a modern passenger car's 35 percent thermal efficiency - https://www.motor1.com/news/655596/video-how-f1-engines-make-1000hp/

So more like 65% goes out the tailpipe...

[–] SARGE@startrek.website 1 points 2 years ago (3 children)

I'll have you know 65% does not go out of my tail pipe.

It goes out a hole in the exhaust manifold that I'm too poor to patch up.

[–] clickyello@lemmy.world 1 points 2 years ago

oof. fuckin felt

[–] Mac@mander.xyz 1 points 2 years ago (1 children)

If you take it off I'll weld it for you.

[–] kautau@lemmy.world 1 points 2 years ago

Is this the modern day version of getting beads at mardi gras

[–] Akasazh@feddit.nl 1 points 2 years ago

I have Keiko patch up mine

[–] BakerBagel@midwest.social 1 points 2 years ago

If your rolling coal, you are literally pumping unused diesel fuel out the car. You're efficiency is absolute dog shit.

[–] zurohki@aussie.zone 1 points 2 years ago (1 children)

It's even worse when you take a bunch of the small percentage of energy the heat engine successfully turns into motion and then use it to heat up the brake discs.

Being able to recapture kinetic energy into a battery and reuse it later helps overall efficiency a lot.

[–] MonkderVierte@lemmy.ml 0 points 2 years ago (2 children)

Plug-in hybrid? Aren't they worse than both, because of the weight of motor and battery?

[–] Yaky@slrpnk.net 1 points 2 years ago (1 children)

Series plug-in hybrids that can run on battery (Chevy Volt, Honda Clarity, Prius 2024) are IMO better than both. They effectively operate like electric vehicles (regenerative braking and all), and one can drive them for months without burning gas. Their batteries are about five times smaller (~30-50mi range vs full EV's ~250mi range), and thus lighter, and the gasoline engine is usually a small, efficient one (~40ish mpg on gas)

[–] Swedneck@discuss.tchncs.de 1 points 2 years ago

it's a classic case of one implementation of a concept being really good, but for some utterly baffling reason everyone tries the shitty implementation of the concept instead and so everyone discounts the whole thing as a bad idea.

drinking water is a good idea, but for some reason everyone only tries drinking dirty puddle water and conclude that water gives you parasites.

[–] CouncilOfFriends@slrpnk.net 1 points 2 years ago

You also get to use a smaller lighter ICE motor which is augmented by nearly instantaneous electric power. My favorite car was a Prius C which is no sportscar, but feels much zippier than you would expect for getting 50 mpg.

[–] Mac@mander.xyz 1 points 2 years ago

Well-To-Wheel energy efficiency:

Gasoline: ~20%
Diesel: ~30%
H Fuel Cell: ~25%
BEV (fossil power): ~20%*
BEV (renewable): ~55%*

*BEV is highly dependent on energy source. Anwhere from ~20% WTW from natural gas power generation to 75% from roof-mounted solar.

Keep in mind this is a summary of a summary of a summary.

Sources: