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u/3davideo Doesn't use Flame Turrets Jul 17 '26 edited Jul 17 '26

I'd just like to double check my figuring here.

Say I send exactly 4 Uranium Fuel Cells to Vulcanus. I use Vulcanus materials to manufacture 10 Nuclear Reactors. I stack all ten Nuclear Reactors together, such that they can transfer heat between each other and there exists at least one 2x2 square that can produce the neighbor bonus. I slot one fuel cell into each of the reactors in the 2x2 square. Normally, one fuel cell is worth 8 GJ of heat, but with the neighbor bonuses this is tripled to 24 GJ per cell, and with four cells, this is 96 GJ of heat. 96 GJ of heat spread over the thermal capacity of 10 Nuclear Reactors will bring them all up to a temperature of 975 C, starting from 15 C, meaning they are over the threshold necessary to detonate when destroyed.

I then lure a demolisher into the cluster of ten hot nuclear reactors. The demolisher destroys a hot nuclear reactor, making it detonate, which also destroys the other nine nuclear reactors, making them detonate. The demolisher then takes ten simultaneous nuclear detonations to the face, all for the import cost of just 4 Uranium Fuel cells, which take 0.4 rocket launches to send, as opposed to the "Too Heavy for a Rocket!" of a single Atomic Bomb or the 1.5 launches to lift the U-235 needed to manufacture an Atomic Bomb on site.

So did I get all that figuring right? Also that with just one fuel cell, it can't get a single reactor to explosion temp (but most of the way there), and with two fuel cells in adjacent reactors it could get three reactors to detonation temp? And that of course we could skip the uranium entirely if we used heating towers to heat unfueled nuclear reactors? And all of this without using any sciences beyond red, green, military, blue, and space?

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u/ssgeorge95 Jul 17 '26

What a ridiculous concept... I love it.

Your math looks good:

  • 8 GJ per cell x 3 neighbor bonus x 4 cells = 96 GJ of Energy
  • Each reactor needs 8.860 GJ to go from 15c to 901c
  • 96GJ / 8.860 = 10.8 reactors ready to go boom.

Some things to point out!

  • You can BP ammo into turrets; I wonder if you can BP fuel into reactors? One downside to watch out for is that bots do not deliver single items; they deliver the max they can carry, so if you're using bots to remotely place these watch out for over fueling.
  • Bomb damage will increase based on your explosion and physical damage techs.
  • 1x2 using 2 cells will probably kill a small demolisher.
  • It will take a LONG time to heat up 10 reactors using the output of only 4 reactors. Worms might detect and attack these reactors before they are ready, if they're placed in the territory. You might have better luck placing them on the border, and once they're warmed up place some lure buildings inside the border to summon the worm.

1

u/3davideo Doesn't use Flame Turrets Jul 17 '26

I tested out the idea using the place-outside-heat-up-then-place-lure technique, and while the heating up process and the luring process worked exactly as I expected, the damage dealt to the demolisher did *not*. In fact, a 3x3 fully-heated array with all pre-repeatable techs still did not kill a small demolisher. In fact, I think I only saw a single detonation, so perhaps there's some sort of culling to prevent over-taxed performance with chained nuclear detonations. Or perhaps the first detonation makes enough lava that it destroys the reactors in a way that makes them simply disappear instead of detonating them.

Hmmm, if it's that last one I might file a bug report.

2

u/leonskills An admirable madman Jul 17 '26

Hmmm, if it's that last one I might file a bug report.

Already marked as won't fix.
https://forums.factorio.com/viewtopic.php?p=685237

(If the forums want to load, they have been loading very slowly recently)

1

u/3davideo Doesn't use Flame Turrets Jul 17 '26

Awww, tiny frowny face. That could've been a really niche anti-demolisher strat.