@Motodrachen I've seen ammonia mentioned as a possible cleaner-burning fuel before. How does that compare, or does it need to use a completely different thermodynamic cycle?

@Motodrachen As we understand it, the main obstacle to using ammonia as fuel is the fact that it produces extremely noxious combustion byproducts; the ideal reaction would be 4 NH₃ + 3 O₂ → 2 N₂ + 6 H₂O, but the actual reaction produces substantial amounts of mixed nitrogen oxides that need to be dealt with

It's kind of interesting, but I don't think it's a workable fuel, especially not as an environmentally friendly one. You'd need big catalytic converters.

@Motodrachen I think the problem is that it gets too hot and oxidizes the nitrogen beyond N₂. Because nitrogen in ammonia is already reduced to the -3 oxidation state, and then your clean combustion gets it to the 0 oxidation state in N₂, and then things like NO has +2; you've over-oxidized the nitrogen and in the process also consumed some of the energy that would otherwise have gone to propulsion

@Motodrachen I think the idea is that it'll be possible to avoid that by controlling engine temperature, but it seems like a bit of a lost cause to me. It's an interesting thought, though, to use a fuel that you can make from electricity, air, and water.

@Felthry @Motodrachen I could see that having application in ship engines, maybe. Use the hull as the warm side of a coolant loop.

@Motodrachen Incidentally, have you ever looked at bob's mods for factorio? THAT is the real demonstrator of how difficult processing stuff gets.

@Motodrachen I appreciate the circuitry stuff it does. Needing to etch circuit boards and produce components just appeals to me.

I kinda like the metallurgy aspects too, but I think I'm in a minority among our friends. Processing ores in more realistic ways, and being able to use byproducts of other manufacturing processes to extract more metal, just appeals to me.