Nuclear Reactor

From Official Barotrauma Wiki
(Redirected from Reactor)
Jump to: navigation, search
Version Checkmark False.png
Versioning - Potentially Outdated

Last updated for version:
Current game version:

Nuclear Reactor
Nuclear Reactor.png


Category Machines
Item Slots 4 Fuel Rod slots
Repair Requirements
Mechanical Repairs
Mechanical Engineering 55

The Nuclear Reactor is an installation. It uses fuel rods to produce power to the submarine.


The nuclear reactor's function is to generate power for other installations on the submarine. As long as the reactor is active, every other connected device on the ship will remain active as well. Power generated by the reactor is sent to other installations via wiring. Power distribution requires Junction Boxes to work, as the reactor cannot send power to other installations directly. Maintaining the power network is one of the most important aspects of a round, as the submarine cannot function without power.

The nuclear reactor undergoes nuclear fission, in which atoms are split apart, cause large amounts of energy to be released. The rate at which these reactions take place is measured by the fission rate. The resulting reaction also causes heat to be released that raises the overall temperature of the reactor. If the temperature raises past 6,000 degrees for too long, the reactor will catch on Fire. If the temperature stays over 9000 degrees for too long, it will meltdown, creating a massive radioactive explosion. It is possible to fix the submarine and reactor after a meltdown, but it is difficult due to radiation and lack of power and, often, walls. Because of this, the cooling and fission rates must be adjusted to keep the temperature at a desired level - which is usually the same as the amount of power consumed by the electrical grid of the submarine.

Fuel Rods are required for the nuclear reactor to function. The reactor can hold up to four rods. They will be slowly consumed at a rate proportionate to the Fission Rate. Fuel Rods can be removed and replaced at any time.

If the reactor is in water, it will take damage over time, down to 10% condition.

Even when not in water, a reactor will slowly deteriorate over time, requiring maintenance. A reactor will not deteriorate below 10% condition by itself.

If the reactor reaches 0% condition and has a fuel rod in, it will instantly meltdown.


  • Turbine output

Turbine Output is how much electricity the reactor will output, which will need to be adapted to the ship's consumption. So if 2000kW are required and 1000kW are produced, the turbine output will need to be doubled.

The Turbine in turn works off heat. If there isn't enough heat, then the turbine can't produce the output it is set to. The turbine is merely capped by whether or not it has enough heat. It does not produce more power via excess heat. It only produces as much power as it is set to, as long as it has enough heat to sustain that level of power output.

Note: if the reactor outputs more power than is needed, junction boxes will be gradually damaged.

  • Generating heat

The Fission Rate combined with the fuel rods determines how much heat is available. It is fully linear, so doubling Fission Rate will double the heat output which will allow doubling the power generation by doubling the Turbine Output. Inserting a second rod while halving the Fission Rate will leave the heat unchanged and allow keeping the same Turbine Output and power output without consequences.

Note: if rods are added and/or fission rate is increased but heat is not used by increasing the turbine output, then the reactor overheats and takes damage, eventually leading to a meltdown

Note: if the fission rate is too low, there won't be enough heat and the turbine won't be able to generate the actual output that it has been set to.

  • Fuel rods

Different fuel rods burn hotter for the same fission rate. Maxing out 100% on the Turbine Output requires a Heat Potential of 100. Uranium rods Heat Potential is 80, so they can support 80% of the turbine output (at 100% fission rate). Going past that would require adding a second uranium rod (and halving the fission rate then increasing it a bit to avoid overheating), or replacing it with a single Thorium bar (which has 100 fuel strength) and keeping fission rate maxed.

  • Indicators
    • The yellow line on the graph is the actual power produced.
    • The white line on the graph is the load required by the ship.
    • The middle bar (with the two pairs of red notches) is a temperature indicator. The notches are at 4000 and 6000. If the temperature raises past 6,000 degrees for too long, the reactor will catch on Fire. If the temperature stays over 9000 degrees for too long, it will meltdown, creating a massive radioactive explosion.
    • The green areas on the Fission Rate suggest the supported fission rate for the fuel load.
    • The green area on the Turbine Output suggests the required turbine rate to generate the power load.

Example scenarios
  • There is a spike in load from captain suddenly steering the ship

Load is increased instantaneously, causing a low-power situation while the reactor increases its Fission Rate (which takes a little bit to catch up) and possibly Reaction Rate (unless there was already enough extra heat being generated).

  • There is a drop in load from unplugging oxygen generator

Load is decreased instantaneously resulting in far more power generated than required, which causes damage to the junction boxes until the Turbine Output decreases (and Fission Rate, too, to avoid excess heat).

  • More fuel rods are added to the reactor

More fuel rods without changing the Fission Rate results in dramatically increased heat, causing damage to the reactor and a possible meltdown, unless the Turbine Output is increased to consume that heat. No extra power is generated unless the Turbine Output is increased accordingly.

  • Turbine output is increased without increasing fission rate

Since heat level has not increased, the power generated won't actually go up, and might actually go down. This will be a "temp low" situation.

  • Turbine Output is decreased without decreasing fission rate

The turbine is no longer consuming the heat that is generated, so the reactor will begin to get hotter and possibly overheat and meltdown.


The nuclear reactor's control panel.

When a reactor is selected, a control panel opens up. The panel displays two gauges, a bar graph, and a line graph. They represent the fission rate, turbine output, temperature, and reactor load/output respectively. In this control panel, players can manually set the fission rate and turbine output of the reactor or toggle automatic control.

  • Manual Control

Under manual control, the Fission and Turbine are controlled manually. A player should be stationed near the reactor to adjust the fission and turbine appropriately for the ship's fluctuating power requirements. Manual control can respond to power fluctuations faster than Automatic mode, but requires player attention.

  1. Start the reactor using the button on the top-right labelled "Power". The light next to the button should glow.
  2. Ensure automatic control is off. The light next to the switch should be off.
  3. The sliders beneath Turbine Output and Fission Rate can be drag&dropped. When hovering the mouse over one of the sliders, they can also be adjusted using the keyboard movement keys. Horizontal movement controls the fission rate, vertical controls turbine output (by default: A & D for horizontal/fission, W & S for vertical/turbine).
  • Automatic Control

Automatic Control controls the Fission and Turbine automatically. It reacts to changes in load slower than a human can, but requires little player attention.

  1. Start the reactor using the button on the top-right labelled "Power". The light next to the button should glow.
  2. Turn on automatic control using the switch on the top-right labelled "Automatic Control". The light next to the switch should be on.
  3. The reactor will slowly adjust Turbine Output towards the load and Fission Rate towards the middle temperature (5000).
Connection panel for Nuclear Reactor
Connection Port.png
Connection Port.png
Connection Port.png
When it receives any signal, fission rate and turbine output are set to 0, and reactor is turned off.
Sets fission rate to a fixed percentage (0-100)
Sets turbine output to a fixed percentage (0-100)
Connection Port.png
Connection Port.png
Connection Port.png
Connection Port.png
Connection Port.png
Connection Port.png
Power output of the reactor.
Sends out the reactor's current temperature (0-10000).
Sends a signal of 1 when reactor is high temp (>6000).
Sends the current power level as a number (supplied power).
Sends the current load level as a number (required power).
Sends the cumulative Heat Potential of current fuel rods as a number (see Fuel Rods).

Wire Control

Wire control controls the Fission and Turbine remotely through Wiring Components. Wire control overrides both Automatic and Manual controls. It can also be used to warn about overheating, meltdowns, and used to remotely shut down the reactor. Wiring can change the Fission and Turbine much faster than Automatic, if set calculated properly this can prevent re damage to junction boxes and other electrical devices.

Fuel Rods

Fuel Rod Type Durability Heat Potential Mechanical Skill to Craft Crafting Materials Crafting Time Store Price
Fuel Rod.pngFuel Rod 100 80 25 Uranium.pngUranium

Lead.pngLead Steel Bar.pngSteel Bar

10 135-150 Marks
Thorium Fuel Rod.pngThorium Fuel Rod 200 100 60 Thorium.pngThorium

Lead.pngLead Steel Bar.pngSteel Bar

10 225 Marks
Fulgurium Fuel Rod.pngFulgurium Fuel Rod 150 150 40 Fulgurium Bar.pngFulgurium Bar

Lead.pngLead Steel Bar.pngSteel Bar

10 Not purchasable


When a reactor reaches 0% condition, and if there is a fuel rod in it, it will meltdown, generating a large radioactive explosion. Fuel rods in the reactor will be completely exhausted.

Afflictions on Hit
Structure Damage
Kinematic Force
Explosion Radius (m)
Nuclear Reactor Meltdown
Affliction Burn.png Burn : 200

Affliction Deep Tissue Injury.png Deep Tissue Injury : 50

Affliction Radiation Sickness.png Radiation Sickness : 50

Affliction Stun.png Stun : 5

Outpost Nuclear Reactor Meltdown
Affliction Burn.png Burn : 200

Affliction Deep Tissue Injury.png Deep Tissue Injury : 80

Affliction Radiation Sickness.png Radiation Sickness : 80

Affliction Stun.png Stun : 5


Default Submarines Max Power Output

Submarine Max Output
Azimuth 3,500
Berilia 6,500
Dugong 2,700
Humpback 2,800
Kastrull 10,000
Orca 3,500
R-29 5,200
Remora 5,000
Typhon 5,000
Typhon 2 5,000