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The Nuclear Reactor processes Uraninite Crystal-based Reactor Rods into Energy for use by a Seabase. The Nuclear Reactor is constructed with the Habitat Builder, and can only be placed in the center of a Multipurpose Room or on any of the central positions of a Large Room. While operational, the Nuclear Reactor will continuously hum.

Each Rod contains 20,000 energy, and the Reactor, regardless of the number of Rods inserted, provides 2,500 energy storage.The Reactor operates at a fixed rate of 250 energy per minute (~4.166667 per second) regardless of how many Rods are inserted into it. Thus, it takes a total 10 minutes for the Reactor to fill its 2,500 energy storage capacity (given that nothing else is running/drawing power).

A Nuclear Reactor can hold a maximum of four Reactor Rods. Assuming constant maximum energy drain, a single Reactor Rod will last 80 minutes, but the Rods are only drained if power from the Reactor is being used. When power is being consumed at the base, the Nuclear Reactor's capacity will not drain until all other energy sources are depleted. Once the Reactor Rods are fully consumed, they will turn into Depleted Reactor Rods, at which point they can be removed from the Reactor; they otherwise cannot be removed once inserted (i.e., once a new/non-depleted Rod is inserted, it cannot be removed). Depleted Reactor Rods can be discarded or stored like any other item, but cannot be deleted by a Trash Can; to permanently dispose of them, they must be placed in a Nuclear Waste Disposal.


The blueprint for this module is acquired by scanning the Nuclear Reactor in Omega Lab or the second segment of the Mercury II in the Lilypad Islands. It is crafted with the Habitat Builder.

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Databank Entry

Nuclear Reactor
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Renewable energy sources will usually be sufficient for maintaining a small outpost. For everything else there's nuclear power.

- Powered by up to four replaceable uranium reactor rods
- Do not attempt to replace reactor rods without a full radiation suit
- Do not attempt to overclock the reactor

Nuclear is ideal for energy-intensive operations such as:
- Self-sufficient colonies supporting more than 20 people
- Industrial outposts operating multiple docks and heavy machinery
- Research stations housing live specimens

Source: Unlock the Nuclear Reactor