I wanted to make a dumb joke about how gasoline is too volatile to safely cook food in it as it won't come up to a sterilizing temperature, but today I learned that gasoline's "boiling point" is a complicated situation where it is "between 100 and 400 degrees" depending on it's exact makeup. Makes sense. I always forget that gasoline is a mixture of hundreds of different components.
Besides, lithium is clearly a better substance for heat transfer
Jet aviation fuel is typically kerosene, which has an average carbon chain length of about 10, as compared to diesel which ranges from 12 to 15.
Among critical factors, diesel fuel freezes at far higher temperatures than kerosene, which is important for both aircraft (which typically fly in ambient temperatures about -40 °F/°C) and polar operations. Blends such as Jet A1 and Jet B (kerosene + petrol) have still lower freezing points of -47 °C and -60 °C respectively.
Diesel's freezing temperatures are ~ - 8--9 °C / 15--17 °F. Kerosene and jet aviation fuel are rated to -40 °C / -40 °F (both temperature scales are the same at this temperature).
Piston aircraft burn petrol / gasoline with a freezing point of ~ -73 °C / -100 °F.
Shorter hydrocarbon chain lengths -> lower freezing temperatures. Methane (CH4) is liquid to -182 °C / -195 °F, and only liquifies at -162 °C / -259 °F.
Yeah, with the addition that if you're going to go the synthetic hydrocarbon route you might as well go all the way to a fuel which is a liquid at normal operating temperatures to simplify logistics (and which isn't a massive GHG when it accidentally leaks like methane).
We've been using liquid hydrocarbons capable of thermal runaway (petrol/gasoline) for a century despite the existence of liquid hydrocarbons which are more resistant to ignition (diesel).
LFP chemistry will certainly become increasingly dominant over the next few years, particularly now that key patents have expired. But it doesn't supplant all usages of NMC yet, and isn't likely to for some time.
If you're going for a synthetic hydrocarbon, you might as well go for one which is liquid at normal operating temperatures, which makes logistics a lot easier.
Post like these always make me go into the rabbit hole of how energy dense gasoline is.
The energy density of gasoline is higher than liquid hydrogen! It does not need to be super cooled and is liquid state at atmospheric pressure and ambient temperature.
Gasoline is an absolute miracle fuel. Sort of feels under appreciated to casually pump it at the gas station ha.
You have to compare the compact stored energy of liquid fuels after it gets converted to useful forward motion via a heavy, noisy, inefficient, costly to maintain and fuel engines.
It's basically a thought terminating cliche at this point.
The fuel we're talking about isn't a really good gasoline alternative, anyways. Gasoline isn't mentioned in the article, except as an example of a very volatile, easily ignited fuel.
I was thinking perhaps it's ~30% ammonia near-saturated solution in water which is easier to handle. But there's no indication in video, it would need to be dehydrated before burning, lowering efficiency. Also it means getting from over 12 MJ/l down to 4. Compared to gasoline 34 MJ/l. Would need several hundred liters fuel tank to have comparable range.
It does not occur naturally on earth, takes energy to make, takes energy to compress, is prone to exploding, and is only liquid at extremely low temperatures. Or that's what Musk keeps saying every time he's asked, I'm not sure what the general consensus is among scientists and engineers on the subject. As things stand right now it does not appear to be a useful fuel source for cars.
Well to be fair, regardless of its suitability as a long term viable fuel source, it is nasty stuff. It's basically tar. It has to be kept heated to about 70c less it become to viscous and can't be pumped anymore and heated even more before being used in the engine.
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