
Mekanism Fission Recipe
A mod that allows you to add custom recipe for Mekanism Generators' Fission Reactor.
About this Mod
Mekanism Fission Recipe
A really unique addon for Mekanism Generators.
What?
With this mod installed, you can add actual recipes for Mekanism's Fission Reactor. Below is an example of converting hydrogen to oxygen with the fission reactor that generates no heat:
How?
This mod uses a dirty hack called Mixins. It changes Mekanism's code at runtime. By creating a new recipe type and forcing the Fission Reactor to accept it, you can now add custom fission recipes to Mekanism.
Fission Recipe
You just need to create the recipe like a datapack. Here's how the recipe JSON file should look like:
{
"type": "mekanism:fission",
"input": {
"chemical": "mekanism:fissile_fuel",
"amount": 1
},
"output": {
"id": "mekanism:nuclear_waste",
"amount": 1
},
"heat": 1
}
- Type: Always use "mekanism:fission" if you are adding a fission recipe.
- Input
- Gas: The input gas. If you're making a mod you can add your own gas.
- Amount: Input amount.
- Output: Similar to input.
- Heat: The amount of heat generated. 1 is the amount Fissile Fuel normally creates.
- You can also use equations in this field with x as subject. For example, "x*x" will make burning 0.1mB of fuel generate 0.01 heat.
With version 1.1.0, users can add coolant recipes. There are 2 types of coolant recipes:
Fluid Coolant Recipe
For all fluid (like water) cooling, use this. The following is a sample JSON:
{
"type": "mekanism:fluid_coolant",
"input": {
"tag": "minecraft:water",
"amount": 1
},
"output": {
"id": "mekanism:steam",
"amount": 1
},
"thermalEnthalpy": 10,
"conductivity": 0.5,
"efficiency": 0.2
}
- Type: Always use "mekanism:fluid_coolant" if you are adding a fluid coolant recipe.
- Input
- Fluid/Tag: The fluid to accept. It can be a single fluid type (change
tagtofluid) or a fluid tag (tag). - Amount: Input amount.
- Fluid/Tag: The fluid to accept. It can be a single fluid type (change
- Output:
- Gas: The output gas. If you're making a mod you can add your own gas.
- Amount: Output amount.
- Thermal Enthalpy: Higher = Boil less & Cooler
- Conductivity: Higher = Cooler
- Efficiency: Higher = Boil more
Gas Coolant Recipe
For all chemical (like sodium) cooling, use this. The following is a sample JSON:
{
"type": "mekanism:gas_coolant",
"input": {
"chemical": "mekanism:sodium",
"amount": 1
},
"output": {
"id": "mekanism:superheated_sodium",
"amount": 1
},
"thermalEnthalpy": 5,
"conductivity": 1
}
- Type: Always use "mekanism:fluid_coolant" if you are adding a fluid coolant recipe.
- Input/Output: Refer to Fission Recipe.
- Thermal Enthalpy & Conductivity: Refer to Fluid Coolant Recipe.
This code snippet
is the relationship between thermal enthalpy, conductivity and efficiency.
For More Examples,
Please take a look at the test_recipes directory.
Why?
This is originally implemented in Sky Farm, but I feel like this feature has its own potential, so I took it out, and made it a standalone mod.
Help?
If you find my projects great, you can support me on Ko-fi!
License
This mod is published under GNU GPLv3.
Available Versions
How to Install Mekanism Fission Recipe on Your Server
Order Server
Order a Minecraft Java server with at least 4 GB RAM (6 GB recommended).
Set forge Loader
In the panel under "Egg", select the forge loader and matching Minecraft version (1.21.1).
Install Mod
Open the mod browser in the dashboard and search for "Mekanism Fission Recipe". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.
Compatibility
Mod Loaders
Minecraft Versions
1.21.1, 1.20.1, 1.19.2
Server-side
✓ RequiredRecommended RAM
6 GB(min. 4 GB)Frequently Asked Questions
Mekanism Fission Recipe server crashes on startup – what to do?
Most common cause: wrong forge version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 4 GB RAM is allocated and the loader matches the mod version (1.21.1). You can switch loaders with one click in the panel.
Is Mekanism Fission Recipe compatible with forge and neoforge?
Mekanism Fission Recipe officially supports forge, neoforge for Minecraft 1.21.1, 1.20.1, 1.19.2. The Mado dashboard automatically detects incompatible loader combinations.
Server lagging with Mekanism Fission Recipe – how to optimize performance?
Recommended RAM: 6 GB (per 5 players). Use /spark profiler to check if Mekanism Fission Recipe consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.
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