1103
xkcd #2948: Electric vs Gas
(xkcd.com)
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 19 Jun 2024
1103 points (96.3% liked)
xkcd
8862 readers
27 users here now
A community for a webcomic of romance, sarcasm, math, and language.
founded 1 year ago
MODERATORS
The motors have never been the problem, it's always been the battery. See train engines, they are a diesel generator with electric motors.
This is where history pisses me off. We should have been headlong into battery research after the oil embargoes. Could have been 40 years faster.
I think people forget that petroleum is condensed and distilled solar energy. One gallon of gasoline is the results of years of solar energy.
Spelling
Non renewable solar energy unfortunately.
Renewable fuels exist and are used today, but the efficiency and pollution aspects still apply.
If you're making your diesel from CO2 pulled from the air, pollution aspects don't really apply (at least, CO2 emission issues don't, there's still NOx, but that's what cat piss is for).
Problem is, converting atmospheric CO2 back into fuel makes the efficiency issue drastically worse. Maybe with enough solar panels and windmills, and use the Fischer–Tropsch process with the excess energy that the grid isn't consuming.
Of course, that would be for mobile fuel, if solar plants were going to do anything like that for later use generating electricity during peaks, making diesel is dumb; you'd want to use hydrogen or ammonia for in-place energy storage.
I was thinking about fuels like HVO. They work well, but have their own ecological implications.
Ah. I'm generally skeptical of any plant-based 'green fuel' because they generally take up agricultural capacity that would otherwise be producing food
No, it's renewable. But... not in any practical timeframe.
That's not the definition of renewable.
Not really. Its trees from a time before micro organisms evolved the ability to eat dead trees. These days, the solar energy collected by trees will get used to power the metabolisms of fungi before those trees can get buried and eventually become new coal & petroleum.
I suppose an impact from a sufficiently large asteroid could turn the entire crust of the planet into magma, sterilizing it and therefore opening the possibility that new oil might be created some day.
IIRC it is actually mostly from algea. A small amount from some fern-like plants. By the time trees existed, they were being broken down by bacteria.
I think I read somewhere that oil will not be produced anymore because now bacteria can break down that biomass that it previously didn't. Hence, non-renewable even on long timescales.
Only if we bring back the dinosaurs. There are six movies (and counting!) explaining why this is not a good idea.
Technically no. Only if we erase bacteria capable of breaking down trees.
Energy density is a huge advantage which most people find hard to give up especially when the biggest problem that we face is invisible to most people. We can't fix a problem if we ignore the cause.
Happy cake day!
A lot of people have been having their cake days recently. Guess it's the first anniversary of the Reddit exodus.
oops you posted irrelevant pedantics that verge on misinformation 😧
sure it’s distilled solar energy that cannot be renewed. relevant language highligted. no one “forgets,” this. literally no one. it’s just not relevant to a timespan less than millions of years. cheers! ☀️
Petroleum can't be renewed, but biofuels can be.
v true but i also dislike how biofuels get smorked into yet more CO2 which is kind of a problem rn
Biofuels are carbon-neutral. They release CO~2~ when burned, but it doesn't matter because that same CO~2~ had recently been sucked out of the atmosphere by the plant they came from.
In theory true. In reality not true.
Not passing judgement on anything, just putting the facts out there that I happen to know :) Biofuel may or may not be a good tool to move toward more sustainability, and it’s certainly better than petrol.
My biofuel of choice is biodiesel produced from byproducts of chicken rendering that would otherwise become waste/pollution anyway. ¯\_(ツ)_/¯
The way I see it, we should electrify all the things that can be (urban driving, both freight and passenger trains, etc.), maximize the use of those things (e.g. by shifting long-haul freight away from trucking and back towards rail, and shifting airline travel to high-speed rail), and then use biofuels for the relatively-niche stuff that's left instead of spending excessive effort trying to get electric to cover 100% of cases.
I hope you are not talking about battery locomotives.
With overhead wires the train has a practically unlimited battery capacity.
There are use cases for battery trains. In remote, mountainous locations where the cost for electrifying a track is very high it is not uncommon to use electric trains with batteries. Here in Germany we have several regions where diesel trains have been replaced by them.
Oil is honestly an amazing product, chemistry wise there is so much we can do with it and energy wise it's a extremely concentrated and easily transported form of energy.
Energy wise one liter of oil is equivalent to 10 person working for a day !
I repeat, using one liter of oil is like having 10 "slaves" working for us for a day.
Its easy to see why oil became the base of our modern civilization, and easy to see why we don't manage to stop using it even though it's destroying us.
Source - How much of a slave owner am I ?
Not really. Battery tech has always been advancing. Even today electric vehicles have barely come up with anything new, battery wise. Everyone wants something better than lithium base. No one can get anything to market.
It advanced at a glacier pace because there was no massive driving force. It only kicked off a bit with cell phones and then in any substantial way with laptops. (Yes, batteries existed before that for different things, but there was no massive driving force.) Now imagine what would have happened if we funded it starting in the 1970s.
Didn’t sodium batteries start getting marketed recently?
Yes, but no one's even glancing at it for use in vehicles. The one that's finally getting into production is 70wh/Kg. Not nearly energy dense enough yet for ev's. Lithium batteries are closer to 300wh/Kg. In other words, they take up 1/4th the space and weight. EV's are already a thousand pounds heavier than non ev's and that's already causing extra tire pollution issues and having to overbuild suspension parts and bearings. Making them another 3,000 pounds heavier than that is just out of the question. Let alone making the space to fit the battery.
Sodium is going to change the world with its power storage capabilities connected to solar. Anyone on like 75% of the planet could 100% live off the electric grid problem free with enough solar panels and a big sodium storage battery.
Wasn’t aware that EVs were already that heavy. Then yeah, I guess that’s definitely not feasible, at least not at the moment.
Yep. A size of vehicle wise comparison would be that a tesla model s sedan weighs around 4,600 pounds. A toyota Corolla weighs around 1,600 pounds less at around 3,000 pounds.
Even the newest and most powerful mass produced American made car ever, the "C8 Corvette Z06" with its big V8 gas engine with 670 horsepower weighs in at around 3,650 pounds.
pretty sure most trains are powered by either overhead wires or third rails? considering that urban rail systems are always electrified and those have A LOT of trains.
Freight trains are diesel electric.
Not in America
okay? i'm talking about the world though, so typical for people to just assume america is all that matters lmao
The point is about utilization of electric motors, if it happens anywhere on earth it's possible. You're trying to insinuate that it isn't true. And it is. Being American has nothing to do with it you dunce