Fluid Reactor

From GT New Horizons

Fluid Reactor System

This guide offers a brief overview of the components of a fluid reactor. The high level idea behind a fluid reactor system is: hot coolant is created by passing regular ic2 coolant through a (heat-generating) fluid reactor. The hot coolant is cooled down and recycled with distilled water in a Large heat exchanger. As a result of this process, the Large Heat Exchanger creates absurd amounts of either steam or superheated steam, which is then passed in through an appropriate Large Turbine to turn it into usable EU.

Fluid Reactor


The structure of a fluid reactor is a hollow 5x5x5 cube with a 6 chamber ic2 reactor inside, the walls are primarily made of reactor pressure vessels and a few different blocks that provide access of various kinds. NOTE: ports of any kind can not be placed on the edges of the fluid reactor.

A wireframe that shows the shape of a fluid reactor
A completed fluid reactor
Red borders show invalid locations for ports, green shows valid port locations and is mirrored on all non visible sides.
Access Port

Allows access to the reactor inside the structure for item automation as well as placing or remove components within the reactor.

Fluid Port

Allows the insertion of ic2 coolant into the reactor and the extraction of ic2 hot coolant from the reactor.

Redstone Port

Allows redstone control of the reactor with a high redstone signal being on and no signal being off.


Unlike a regular IC2 nuclear reactor, the fluid reactor does not create power directly. Instead, it converts coolant to hot coolant proportional to the amount of heat vented by the reactor at a rate of 2 HU produced per unit of heat vented from your reactor design per second.

HU/t as stated in the reactor GUI refers to Heat units produce per reactor tick, which happens every 20 ticks in game.

Differences from Normal Reactor Mechanics
  • The heat absorbed a RSH-condensator, or LZH-condensator, is not used to convert coolant to hot coolant
  • All coolant cell variants if heated in a fluid reactor can only be cooled down in a fluid reactor
  • MOX fuels function differently in fluid reactors. Instead of increasing EU output at high heat, they instead double the heatoutput at above 50% heat.

Large Heat Exchanger

The Large heat exchanger converts hot coolant and distilled water to coolant and either steam or superheated steam depending on how much hot coolant is feed into the exchanger, see the large heat exchanger page for full details. You should keep a small buffer of coolant and a way to restore coolant automatically as some can be lost on reactor heat up.

Large High Pressure Turbine

This type of large high pressure turbine converts superheated steam to normal steam and energy. Superheated steam is converted to normal steam at a 1:1 ratio and uses the same fluid flow rates as normal large steam turbines but with double the energy output. As with all large generator, and or steam turbine, types make sure you use fluid regulators to ensure that you are meeting optimal flow if you can for your chosen turbine/fitting type.

Large Steam Turbine

This type of large turbine converts steam to distilled water and energy at 160:1 steam to distilled water and 2:1 steam to eu and its energy output is determined by the turbine item in the controller. This recycling of distilled water is helpful to maintain a neutral water loop where you don’t not have to add more distilled water into the system except to counter any that is lost when warming up the system.

Basic Fluid Reactor System Layout

Shows a high level diagram of a gregtech fluid reactor setup.