Factorio Forums

TL;DR

Make the coal synthesis recipe available to the Cryogenic Plant (or biochamber).

Why

Better way to get oil products in space during late game.
I have not fully tested this yet, but on paper it should work.

Setup:
Have space platform in orbit over Gleba, ship up bioflux. Turn it into carbon/sulfur via spoiled nutrients. Then turn those into coal, and use coal liquefication.

However I foresee that despite this being obviously feasible already, it probably would be much more interesting if there was an endgame boost via cryogenic plants and the productivity boost it provides. (*edit: To a lesser extend also applies to the biochamber.)
When you get to the point of having conquered Aquilo you are easily in a position where you can just make additional space platforms to farm sulfur/carbon that way. Which is interesting once, but duplicating platforms is not peak gameplay for me personally.
Instead giving players this additional route to do novel and fun things in space that are spacially and economically efficient should be fantastic.

It would make a lot more sense to give Coal Synthesis to the Biochamber. It's a recipe unlocked on Gleba and the Biochamber could really use some more reasons to use it on other surfaces. Your only reward for using this building off Gleba is productivity on oil cracking and rocket fuel right now.

This would also be a nice alternative in my opinion

The primary carbon-from-coal recipe can be done in a cryogenic plant. Thus, it can hit +200% productivity, meaning that 2 coal becomes 3 carbon.

If coal synthesis can be done in a cryogenic plant, then it too can hit +200% productivity. This means 5 carbon makes 3 coal.

So you can turn 10 coal into 30 carbon, which turns into 18 coal. A net gain of 8 coal, minus some sulfur. Specifically, it costs 3.3 sulfur from acid (making carbon) and 6 sulfur from coal synthesis, for a total of 9.3 sulfur.

8 coal via liquefaction produces 14 petrol directly, 28 light oil directly, and 91 heavy oil directly. With biochamber processing, 91 heavy oil becomes 170 light oil. 198 light oil becomes 331 petrol, for a total of 345 petrol.

9.3 sulfur, at +200% productivity, costs 46.5 petrol, far less than the 345 petrol you got from liquefaction.

If you do this, you can basically make all oil products for free. OK, they cost water and nutrients for biochamber cracking, but that's still basically a rounding error.

I don't think the developers want that.

Alfonse215 wrote: Wed Jul 15, 2026 3:11 am The primary carbon-from-coal recipe can be done in a cryogenic plant. Thus, it can hit +200% productivity, meaning that 2 coal becomes 3 carbon.

If coal synthesis can be done in a cryogenic plant, then it too can hit +200% productivity. This means 5 carbon makes 3 coal.

So you can turn 10 coal into 30 carbon, which turns into 18 coal.

Unless I missed something, with those numbers 10 coal only become 15 carbon and then 9 coal.