The Fluid Nuke Cult's Guide To Nuclear Power

From GT New Horizons

Welcome, aspirant. Perhaps you're currently suffering from a lack of power while smelting your titanium. Perhaps you've seen the smelting time for tungstensteel or tungsten and those numbers have got you feeling woozy. Or perhaps you've seen our faithful adherents evangelizing on the modpack's Discord. No matter where you're from, all that matters is that you're here now.


GTNH has various forms of power generation utilizing nuclear technology.

  • IC2 Fluid Reactors/Fluid Nukes, available at late EV
  • Fusion Reactors/Donuts, available at end LuV
  • Liquid Fluoride Thorium Reactors, available at [REDACTED]
  • IC2 Wrench/Vacuum Nukes, available at [REPORT FOR RE-EDUCATION, HERETIC]

To encourage adoption of these technologies, the cult has commissioned this document so that all may better understand the glory of nuclear power.

Fluid Nukes (IV-Tier Technology)


The Fluid Nuke utilizes 4 main multiblocks for power generation:

  1. An IC2 Reactor Vessel. This multiblock utilizes a precise arrangement of various components to operate at a specific Heat Unit (HU) level, which converts IC2 Coolant into IC2 Hot Coolant.
  2. A Large Heat Exchanger. This multiblock takes in Hot Coolant and Distilled Water (not regular water), and generates Coolant and Steam (either regular OR superheated). For maximum power output, we aim to generate Superheated Steam.
  3. A Large High Pressure Steam Turbine (HP Turbine). This multiblock takes in Superheated Steam, generating energy and regular steam.
  4. A Large Steam Turbine (LST). This multiblock takes in Regular Steam, generating energy and distilled water.

Generally, when the term "Fluid Nuke" is used, we are talking about the entire system as a whole, not just the main reactor vessel

Other useful systems for harnessing and maximizing the potential of the fluid nuke system are:

  1. A very large central energy storage system, usually either a Power Sub-Station or Lapotronic Supercapacitor. High capacities are preferred as the strength of the fluid nuke system is sustained power generation, as well as to minimize losses during system throttling-up and throttling-down.
  2. A distilled water regenerator, usually a HV/EV-tier Distillation Tower. This is a critical system to prevent catastrophic system failure, as the Large Heat Exchange must always have distilled water available or it will explode.
  3. A coolant regenerator, usually a MV-tier Mixer. This is a sub-critical system to ensure enough coolant is present for operation of the fluid nuke system.

Reactor Vessel


The IC2 Reactor is the heart of the fluid nuke system. It is a 5x5x5 multiblock, and to construct one, you will need:

  1. 1 IC2 Nuclear Reactor block. This will be at the center of the multi.
  2. 6 IC2 Reactor Chamber blocks, 1 on each face of the Nuclear Reactor block.
  3. Up to 98 Reactor Pressure Vessel blocks, fully surrounding the central core in a hollow 5x5x5 cube shell. Realistically, you will only need 93 (see below)

Regarding the external shell, the 3x3 faces of the reactor's six sides can be substituted with the following blocks essential for control and operation of the reactor:

  1. At least 3 Reactor Fluid Ports. 1 port will be used to input Coolant into the reactor, while 2 ports will be used to export Hot Coolant from the reactor. Take note that Reactor Fluid Ports do not automatically export Hot Coolant. You will need a Fluid Ejector Upgrade, and each 1 has a flow-rate of 1000mb/s.
  2. At least 1 Reactor Redstone Port. This is essential for automatic toggling of the reactor between On/Off.
  3. At least 1 Reactor Access Hatch. This is essential for access of the reactor's internal components through the external shell.


Interacting with the Reactor Access Hatch enables access to the internal reactor interface: a 6x9 grid wherein reactor components can be arranged. Use of the IC2 Reactor Simulator is not just recommended, but essential in order to prevent catastrophic malfunction.

[placeholder for reactor setups and corresponding material counts]


Once your reactor is properly set up, it can be activated by providing a redstone signal to the Reactor Redstone Port. During operation, most reactors will oscillate around an average HU/s value and maintain a heat level from 0-1%. To ensure safe operation, supply the reactor with an ample buffer of Coolant and drain Hot Coolant readily.

A good recommendation is to use Super Tanks (of varying tier) to store both Coolant and Hot Coolant. Through use of Fluid Detector covers, redstone logic and RS-Latches, activation of the reactor can be triggered when Hot Coolant levels drop below a threshold and stopped when Hot Coolant levels rise above a threshold.

Large Heat Exchanger


The Large Heat Exchanger is the lungs of the fluid nuke system. It is a 3x4x3 multiblock, and to construct one, you will need:

  1. 1 Large Heat Exchanger controller.
  2. 1 Maintenance Hatch
  3. 2 Input Hatches, 1 for Hot Coolant (min ULV-tier) and 1 for Distilled Water (at least HV-tier+ for safety)
  4. 2 Titanium Pipe Casings
  5. 3/4 Output Hatches, 1 for Coolant (min ULV-tier) and 2/3 for Superheated Steam (1 EV-tier + IV-tier or 3 EV-tier).
  6. At least 20 Stable Titanium Machine Casings, realistically 26 or 27.


The Large Heat Exchanger strictly only accepts Hot Coolant from the top-center and outputs Coolant from the bottom-center. However, it is not as strict with the placement of the Distilled Water input and the Superheated Steam output, which can go almost anywhere else on the multiblock.

The Large Heat Exchanger will only produce Superheated Steam with a Hot Coolant input of at least 800mb/s, up to a maximum of 1600mb/s. To ensure that we always produce Superheated Steam, we can use a MV-tier pump cover to feed the Hot Coolant input hatch.

The 3 EV-tier (or 1 EV-tier + 1 IV-tier) output hatches provide a maximum capacity of 384kmb, which is greater than the Large Heat Exchanger's maximum output of 320kmb/s. Ensure that your steam piping is capable of handling this flow rate, or use AE P2P.


It is not recommended to store the Superheated Steam generated by the Large Heat Exchanger in a buffer tank, due to the colossal quantity produced per second, and the ability to use the turbines to regenerate Distilled Water. Instead, we can read the energy levels of your energy storage block of choice, and operate a RS-latch to control the Large Heat Exchanger's activity.

Either we directly control the Large Heat Exchanger's activity with a Machine Controller cover, or we use a Machine Controller Cover + MV-tier pump on the Hot Coolant buffer tank (with the pump set to Conditional Operation) to control Hot Coolant output in accordance with energy storage levels. Use of the second method may be more optimal, as you can optimize Superheated Steam generation rates to your turbine setup.

Distilled Water converts to Superheated Steam at a rate of 1:160, and your Large Heat Exchanger will explode catastrophically if the Distilled Water ever runs out.

Output of both Superheated Steam and Coolant

Large High Pressure (and regular) Steam Turbines


The Large HP (and regular) Steam Turbines are the arms and legs of the fluid nuke system. Both are 3x3x4 hollow multiblocks. To build the HP turbine, you will need:

  1. 1 Large HP Steam Turbine controller block.
  2. 1 Maintenance Hatch
  3. 1 Input Hatch (at least EV-tier) for Superheated Steam
  4. 1 Output Hatch (at least EV-tier) for Steam
  5. 1 Dynamo Hatch (at least EV-tier buffered)
  6. 29 Titanium Turbine Casings

To build the regular turbine, you will need:

  1. 1 Large Steam Turbine controller block.
  2. 1 Maintenance Hatch
  3. 1 Input Hatch (at least EV-tier) for Steam
  4. 1 Output Hatch (at least ULV-tier) for Distilled Water
  5. 1 Dynamo Hatch (at least EV-tier buffered)
  6. 29 Turbine Casings


To make our turbines functional, we will also need the following for each Large Turbine multiblock:

  1. 1 Large Turbine (item). Recommended materials are Desh (cheap and plentiful on Mars), Manyullyn or Oriharukon.
  2. 1 IV-tier Fluid Regulator. This goes on the Input Hatch.

Configure the Fluid Regulator to match the optimal flow rate for the turbine material of choice. Desh has an optimal flow rate of 60kL/s (3kL/t), Manyullyn has an optimal flow rate of 75kL/s (3.75kL/t), and Oriharukon has an optimal flow rate of 98kL/s (4.8kL/t). For these 3 recommended turbine materials, the maximum energy output is less than 1A IV, so use of an IV Dynamo Hatch or buffered EV Dynamo Hatch is acceptable.

With appropriately large-capacity pipes, connect the Superheated Steam output hatches of your Large Heat Exchanger(s) to the Input Hatches of your Large HP Steam Turbines, and connect the Steam output hatches of your Large HP Steam Turbines to the Steam input hatches of your Large Steam Turbines.

Connect the Distilled Water output hatches of your Large Steam Turbines to your Distilled Water buffer tank.


Generally, there is no need to directly control the operation of your HP and regular steam turbines, as they will automatically throttle up and down from 0% efficiency to 100% efficiency when provided with the optimal flow rate of Superheated/regular Steam.

However, it is definitely recommended to use Needs Maintenance covers to pass a redstone signal to a Redstone Lamp to allow for visual monitoring of the maintenance status of your turbines. Full (100%) recovery of Distilled Water is only accomplished when the turbines are operating at max (100%) efficiency.

Superheated Steam converts to EU and Steam at a 1:1:1 ratio in the Large HP Steam Turbine.

Steam converts to EU and Distilled Water at a 160:80:1 ratio in the Large Steam Turbine.

Auxiliary Systems

Energy Storage

The strength of the fluid nuke is its ability to output power for a dreadfully long period of time. So long, in fact, that assuming use of thorium fuel rods, a fluid nuke will have a minimum operation time of 10 thousand seconds between fuel changes, or about 2 hours and 46 minutes. During which, assuming use of a 800HU design (a suboptimal assumption), you can generate a total of 2.4 billion EU per fuel rod lifetime. Ensure that whichever energy storage solution you choose has a minimum storage capacity of 2.4 billion EU, to make the best use of your fluid nuke system.

Distilled Water Generation

The most critical auxiliary sub-system, construction of a 3-height Distillation Tower to read Distilled Water levels from the buffer tank and begin operation should Distilled Water levels drop beneath a threshold is essential to delay or avert altogether a catastrophic explosion of your Large Heat Exchangers.

If possible, select 4 levels of Distilled Water from which to trigger 4 possible outcomes:

  1. Level 0 should be the highest of the four. This is a safe threshold value, and ideally should be maintained or exceeded throughout system operation.
  2. Level 1 is the 2nd highest level. If Distilled Water levels drop below Level 1, engage operation of the Distillation Tower, only stopping when Level 0 is reached.
  3. Level 2 is the 2nd lowest level. Should Distilled Water levels drop below this, use alarms (either auditory or visual) to catch player attention. Normally, having Distilled Water levels drop to this critical value is a sign of maintenance issues at various points in the fluid nuke system. Ensure that all maintenance issues are fixed promptly.
  4. Level 3 is the lowest level. Should Distilled Water levels drop below this, scram the reactor or stop Hot Coolant flow into the Large Heat Exchanger.

Coolant Generation

Less critical than the above but still necessary is a system to read Coolant buffer tank levels, and commence Coolant production should levels drop below a critical threshold. This is not as critical as the Distilled Water generation system, as the Reactor Vessel will melt and automatically scramble the reactor should heat levels grow too high, aborting reactor operation automatically.


For a given (sub-optimal) reactor design of at least 800 HU/s, we will achieve:

  • 800 L/s of Hot Coolant generated
  • 800*200 = 160 kL/s (8 kL/t) of Superheated Steam generated
  • 160000/160 = 1 kL/s of Distilled Water consumed

Assuming 100% use of the Superheated Steam:

  • 8000 EU/t generated (3-4A EV)
  • 160 kL/s (8 kL/t) Steam generated

Assuming 100% use of the Steam:

  • 4000 EU/t generated (2-3A EV)
  • 160000/160 = 1kL/s of Distilled Water regenerated

Thus, overall energy generation even with a sub-optimal reactor design (800 HU) will allow us to generate 12000 EU/t (1.5A IV). Double all the numbers for the maximum operational capacity of a single Large Heat Exchanger (1600 HU = 1600 L/s of Hot Coolant), and it is clear that a proper fluid nuke can generate 3A IV right off the bat.



Fusion Reactors (LuV+ Tier) (under testing, do not try yet)


The Fusion Reactor is a LuV+ technology that allows the creation of heavier elements by fusing together lighter elements. While generally used to synthesize elements needed for LuV+ crafting, for the purposes of power generation there is 1 go-to recipe: the fusion of Helium Plasma from Deuterium (centrifuged from Hydrogen or pumped from Proteus) and Helium-3 (fluid-drilled from extra-terrestrial locations).

Helium Plasma has an energy content of 81.92 million EU per cell (containing 1000L), and as with all turbine multiblocks, the actual energy recovery depends on the turbine item within.

The direct method for extracting power from fusion utilizes 2 multiblock systems:

  1. A Fusion Reactor to produce Helium Plasma
  2. At least 1 (usually more) Large Plasma Turbine to convert Helium Plasma into Helium Gas and energy.

However, the cult has recently performed some science. Thus, we present a novel, indirect method, which requires 4 multiblock systems:

  1. A Fusion Reactor to produce Helium Plasma
  2. An Extreme Heat Exchanger to convert Helium Plasma and Distilled Water into Helium Gas and Supercritical Steam
  3. A SC (Supercritical) Steam Turbine to convert Supercritical Steam into energy and regular Steam
  4. A XL Steam Turbine to convert regular Steam into energy and Distilled Water.

Fusion Reactor

We call it the donut, and you can learn more about it here.

Extreme Heat Exchanger


The Extreme Heat Exchanger is an oddly-shaped multiblock, occupying a volume of 11x6x5 (LxHxW) but with the 4 pillars at the 4 corners missing.

To construct one, you will need:

  1. 1 Extreme Heat Exchanger controller block.
  2. 1 Maintenance Hatch
  3. 3 Input Hatches, 1 for Helium Plasma (ULV-tier) and 2 for Distilled Water (at least ZPM-tier)
  4. 3 Output Hatches, 1 for Helium Gas (ULV-tier) and 2 for Supercritical Steam (also at least ZPM-tier)
  5. 48 Pressure Resistant Vessels
  6. 60 Tungstensteel Pipe Casings
  7. 72 Reinforced Glass
  8. 118 Robust Tungstensteel Machine Casings


The Extreme Heat Exchanger will always produce Supercritical Steam when fed with plasmas, and with Helium Plasma the maximum input rate it will accept is 800 L/s (or 40 L/t). However, for that plasma input, the Extreme Heat Exchanger will generate 1966080 L/s (98304 L/t) of Supercritical Steam, and consume 1228800 L/s (61440 L/t) of Distilled Water. As can be seen, 98304/61440 = 1.6, showing that the conversion ratio of Distilled Water to Supercritical Steam is 1:1.6.

Ensure that your Distilled Water buffer tank is directly connected to the Distilled Water Input Hatch, and is always fed with a ZPM-tier (or better) pump. Do not feed with a P2P Fluid connection, to avoid unwanted detonations.

It is recommended to install 2 safety circuits into your Extreme Heat Exchanger - Plasma buffer tank - Distilled Water tank to automatically scramble EHE operation.

  1. Use a P2P to deliver the Helium Plasma from your buffer tank to your Extreme Heat Exchanger, by having a Fluid Regulator output into a Fluid P2P connection to the Extreme Heat Exchanger's Input Hatch for Helium Plasma. This is so that if the ME system controlling fluid delivery has an issue, the flow of plasma to your EHE will be cut, preventing detonations.
  2. Place a second tank directly adjacent to your Helium Plasma buffer tank. On the main storage tank, place a Machine Controller Cover and a pump (ideally ZPM-tier or higher) set to Conditional: Active without Redstone Signal. Link the Machine Controller Cover to an inverted Fluid Detector Cover on your Distilled Water buffer tank, set to trigger when Distilled Water levels drop below 50% (the actual amount must be set by you). This will ensure that should Distilled Water levels drop below 50%, the plasma stored in the tank will be dumped into the secondary tank, cutting plasma input to the Extreme Heat Exchanger.


Use a Machine Controller Cover on the Extreme Heat Exchanger controller block and link it to a lever. Have that same lever control Helium Plasma export from the plasma storage tank.

As with its little brother, the Large Heat Exchanger, the Extreme Heat Exchanger will detonate violently if it ever runs dry of Distilled Water. Be careful.

Supercritical Steam Turbine


The Supercritical Steam Turbines is similar to its more mundane cousins, the Large HP & Regular Steam Turbines. A 3x3x4 hollow multiblock, to build it you will need:

  1. 1 SC Steam Turbine controller block.
  2. 1 Maintenance Hatch
  3. 1 Input Hatch (at least HV-tier) for Supercritical Steam
  4. 1 Output Hatch (at least ZPM-tier) for Steam
  5. 1 Dynamo Hatch (at least UV-tier buffered)
  6. 29 SC Turbine Casings


Specifically for the use of Helium Plasma, we will want to construct 22 such turbines: 20 using large Oriharukon turbines, and 2 using large Naquadah Alloy turbines.

For the 20 Oriharukon-using turbines, we will use IV-tier Fluid Regulators to limit Supercritical Steam input to 4800 L/t. We will use UV-tier buffered Dynamos to handle the 4800*100*1.5 = 720 000 EU/t (1.373A UV) generated.

For the 2 Naquadah alloy-using turbines, we will use EV-tier Fluid Regulators. For 1, we limit Supercritical Steam input to 1200 L/t. For the other, we limit input to 1104 L/t. Both will use ZPM-tier buffered Dynamos to handle the 1200*100*1.5 = 180 000 EU/t (1.373A ZPM) and 1104*100*1.5 = 165 600 EU/t (1.263A ZPM) generated.

Because fluid regulators strangely do not accept output from Fluid P2P, we will output the Supercritical Steam to a High Voltage Fluid Tank, and then use a pump cover facing directly to the Fluid Regulator to force the output.

In the Supercritical Steam turbine, Supercritical Steam converts to EU and Steam in a 1:100:100 ratio. Thus, the Oriharukon turbines will generate 480000 L/t of regular Steam, and the Naquadah Alloy turbines will generate 120 000 L/t and 110 400 L/t, respectively. For simplicities sake, we will use ZPM-tier Output Hatches to receive and export the Steam through Fluid P2P to the next stage of power generation.


We will use redstone and Machine Controller covers on the turbine controller blocks to force the turbines to throttle up immediately once Supercritical Steam becomes available. We will also use Needs Maintenance covers and Redstone Lamps to provide a visual indicator when the turbines require maintenance.

In total, the 20 Large Oriharukon turbines will generate 720 000 *20 = 14 400 000 EU/t, while the 2 Large Naquadah Alloy turbines will generate 345 600 EU/t, for a grand total of 14 630 400 EU/t, or slightly under 29A UV.

XL Steam Turbines


The XL Steam Turbine is a complicated structure to build. Use the blueprint item to know where the required blocks go.

It is a 7x9x7 (LxHxW) multiblock, and to construct 1, you will need:

  1. 1 XL Steam Turbine controller block
  2. 1 Maintenance Hatch
  3. 1 Input Bus
  4. 1 Output Hatch (ZPM-tier) for Distilled Water
  5. 1/2 (Slow/Fast mode) ZPM 4A Dynamo Hatch.
  6. 4 Muffler Hatches (at the 3x3 ring surrounding the controller)
  7. 3/8 (Slow/Fast mode) Input Hatches (ZPM-tier) for Steam
  8. 12 Rotor Assemblies
  9. 30 Turbine Shafts
  10. 387/381 (Slow/Fast mode) Reinforced Steam Turbine Casings

We will also need 12 Large Trinium turbines per XL Steam Turbine.


For our setup, we will use a 10-2 fast-slow setup.

10 XL Steam Turbines (with a total of 120 Large Trinium turbine items inside) will be screwdrivered to operate in Fast-Tight mode. The 8 ZPM-tier Input Hatches for our Fast XLs will have ZPM-tier Fluid Regulators set to restrict Steam input rates to 115 200 L/t on each Input Hatch, for a total input rate of 921 600 L/t. Accordingly, the energy generation will be 921 600 * 0.5 * 1.8 = 829 440 EU/t (6.328A ZPM), and thus we will use 2 ZPM 4A Dynamo Hatches.

2 XL Steam Turbines (with a total of 24 Large Trinium turbine items inside) will be screwdrivered to operate in Slow-Tight mode. The 3 ZPM-tier Input Hatches for our Slow XLs will have ZPM-tier Fluid Regulators set to restrict Steam input rates to 102 400 L/t on each Input Hatch, for a total input rate of 307 200 L/t. Accordingly, the energy generation will be 307 200 * 0.5 * 1.8 = 276 480 EU/t (2.109A ZPM), and thus we will use 1 ZPM 4A Dynamo Hatch.

Again, we will use tanks to serve as spacers to accept the Steam output via the Fluid P2P. 1 Super Tank I will be used per Input Hatch, and ZPM-tier pumps will be used to immediately export the steam into the XL Turbine's Input Hatches.

Distilled Water generated during turbine operation will be collected from the Output Hatches and returned to the Distilled Water buffer tank via dedicated Fluid P2P.


Like before, we will use redstone and Machine Controller Covers to force the XL turbines to operate the instant that Steam becomes available in their input hatches.

In total, the 10 XL Steam Turbines operating in Fast-Tight mode will generate 829 440 * 10 = 8 294 400 EU/t, and the 2 XL Steam Turbines operating in Slow-Tight mode will generate 276 480 * 2 = 552 960 EU/t, for a total generation of 8847360 EU/t, or slightly under 17A UV.


Once again, let us look at the system from an overhead view. We consume 40 L/t of Helium Plasma, and in the end, we generate 14 630 400 EU/t from the Supercritical Steam turbines and 8 847 360 EU/t from the XL Steam turbines, for a grand total of 23 477 760 EU/t, or 44.78A UV.

The direct energy value of 40L of Helium Plasma is 81920 * 40 = 3 276 800 EU, or 6.25A UV.

By running the Helium Plasma through this energy extraction system of 1 Extreme Heat Exchanger, 22 Supercritical Steam Turbines, and 10+2 (Fast + Slow) XL Steam Turbines, we are able to extract 44.78/6.25 = 7.1648, or basically, 7 times as much energy versus direct plasma turbines.

Wrench/Vacuum Nukes

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