We can possibly do the oxygen thing if someone explains why it makes tons of sense, and why it adds gameplay value. I don't mind it as a pollution workaround because acquiring the oxygen generates its own problems.
The idea itself also has a minor design conflict that would need to be resolved: the plasma turbine accepts various chemical liquids for reactions. Currently Oxygen is NOT one of those inputs. If we implemented this, either
a) we could never use oxygen in a reaction, or
b) we would have to exclude the Plasma variant from the "large turbines that need liquid oxygen" scheme.
or c) we'd have to design a new hatch, or a method to flag a hatch as the oxygen hatch
(b) would be the best option, but "exceptions to the rule" should always be a last resort in game design.
Plasma is fusion tier tech, they shouldn't be affected by pollution and don't make sense to use oxygen either because plasma energy generation doesn't look like to be a chemical reaction in the first place. You're not burning plasma with oxygen to produce heat or anything of the sort
---something that is not relevant to pollution---
Isn't plasma just a very hot fluid, which should be the job of a large plasma heat exchanger? (because plasma is too hot and would burn down the regular LHE into ashes)
Fun how we'd go back to steam... or another fluid should be created that expands like steam when its hot, which I don't know.
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Oxygen would be an optional fluid input, not necessary for the operation, but grants 100% efficiency if present, nullifying the pollution problem at the cost of another one, obtaining oxygen.
Pollution is what decreases the oxygen quality in the air (which is used to burn things).
You know that things burn because theres oxygen in the air and if you pump oxygen in, things burn faster, stronger and more efficient (no partial combustion is done [C + 1/2O = CO]).
This is done in some kinds of blast furnaces nowadays.
THIS is what I mean by a "can do" implementation of dirty water. It works. If there's a pollution factor nearby, machines can't use normal water anymore. Keep it on the board.
NEGATIVES: It totally lacks Axle's flavour. Its only 10% in the fun direction whereas I'd prefer to take it further: where real, dirty water is actually a thing.
Do both then. Dirty water on environment that poisons (or even kills if the water is too polluted) any entity that comes in contact with and blockage of "regular" water on recipes.
Environmental water is very dirty if compared to regular water, but both are polluted enough that they can't be used for recipes.
Dirty water can be purified into distilled water via filtering-distilling process (dirty water + Tcentrifuge = distilled water + sulfur and other crap).
"Regular" water can be distilled with already existing processes.
This way we get both flavour and functional dirty water.