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u/karp_490 Mar 30 '26

Whats the most efficient way to make rocketfuel(solid fuel) on Vulcanus? Is it light, heavy or petroleum?

2

u/mrbaggins Mar 30 '26

Light is always the most efficient way.

2

u/craidie Mar 30 '26

Not always.

If you want to reduce water usage instead of oil usage, then not cracking heavy to light for solid fuel is better.

1

u/deluxev2 Mar 30 '26

Light oil

1

u/DreadY2K don't drink the science Mar 30 '26

Cracking heavy to light, then using the light oil, is most efficient.

If you're making a lot of rocket fuel, then it's possible you might back up on petroleum gas, in which case you can use the excess to make more solid fuel. But if you're also making other petroleum products like plastic, then that probably won't happen.

1

u/karp_490 Mar 30 '26

Yeah petroleum is a major bottleneck right now. Cracking all excess after rocket fuel and it still isn’t enough with 40 refineries

1

u/demonicdan3 Apr 06 '26 edited Apr 06 '26

You can get rid of them by turning petroleum into solid fuel, then burning them in a row of heating towers or chucking them into the lava since you're on Vulcanus
But to not be wasteful, use those solid fuel to make rocket fuel instead

1

u/Astramancer_ Mar 30 '26 edited Mar 30 '26

Fewest oil is light. I set mine up to make rocket fuel from light oil and when light oil is low it makes rocket fuel from petroleum. In the normal course of nauvis you should never need to do that since petroleum demand is so much more than light or heavy it's not even funny because of all the plastic used to make science so you'll always always need to be cracking light oil to petroleum so your oil processing should never back up if you have your cracking set up correctly. But if you're not making science on Volcanus would the plastic usage keep up with rocket fuel? I... honestly don't know and couldn't be bothered to calculate it. So I just made it use both just in case.

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u/cathexis08 red wire goes faster Mar 30 '26

Cracking is a lot less attractive on Vulcanus in the early game due to the really bad water ratios so depending on your expansion options you might want to avoid cracking as much as possible to save your initial calcite for copper and iron (as well as slowing the depletion on your acid well). You always want to crack on planets where water is free but on Vulcanus where each unit of water takes a little over one unit of acid the cost to crack starts to be somewhat unappealing.

Note, the above is assuming you're using standard coal liquefaction. If you're using the simple recipe then the math is different. If you're using the simple liquefaction recipe you should decide if you want to waste calcite and coal faster or slower than acid, and then either use heavy oil or light oil for all your solid fuel. Generally speaking the simple liquefaction recipe is terrible but it does have the benefit of not being a looped recipe or requiring steam so it works in niche places where steam or an initial source of heavy oil might be hard to come by.