Supported versions: 1.12.2, 1.16.5, 1.18.2, 1.19.2, 1.20.1
What’s It All About?
This addon introduces a new layer of challenge and depth to the Mekanism Fusion Reactor. Your main objective is to keep the Current Reactivity (CR) as close as possible to the Target Reactivity (TR). The closer they are, the better your Reaction Efficiency — resulting in more energy, steam per tick, or heat output.
But it’s not just fire-and-forget anymore.
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If Efficiency drops below 80%, your Error Level will begin to rise.
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At 100% Error, the reactor shuts down automatically.
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And if you’ve enabled explosions in the config (disabled by default), it might just go BOOM 💥.
On the flip side:
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If Efficiency stays above 80%, the Error Level will slowly decrease over time.
Reactivity Is Unstable
TR (Target Reactivity) is a random value between 0 and 100, and it changes periodically, making it impossible to just "set and forget" your reactor. You'll need to either manually control it or create some kind of automation logic — redstone, integrated computers, or external mods.
Watch the Heat Multiplier (HM)
HM affects how fast the Error Level changes and how frequently TR updates.
Lower HM = Longer time between TR changes and slower Error Level gain
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For manual control, try to keep HM as close to 0 as possible
HM depends on:
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Plasma Temperature – Adjust your injection rate to find the sweet spot
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Cooling Type – Water cooling results in a lower Heat Multiplier
Bottom Line:
If you want maximum energy output, you’ll need to automate your reactor control.
Manual operation is possible… but it won’t be easy.
Good luck, engineer.













