How to Get the Nuclear Reactor Blueprint in Subnautica 2

Why You Want the Nuclear Reactor

The Nuclear Reactor is the most powerful base power source in Subnautica 2, delivering up to 2500 W with four uranium fuel rods. It works at any depth, in any biome, and requires no sunlight or heat source. For deep bases and power-hungry setups with water filtration machines and multiple battery chargers, nothing beats nuclear. This guide shows you how to unlock and build it.

Where to Find Nuclear Reactor Fragments

The Nuclear Reactor blueprint is unlocked by scanning fragments found in deeper wrecks. Unlike the Seamoth, these fragments do not spawn in the safe shallows. You need to explore mid-depth wrecks to find them.

Best Fragment Locations:

• Grassy Plateaus deep wrecks (150-250 m): Large wrecks in the deeper grassy plateaus often contain Nuclear Reactor fragments. Bring a Seamoth with a depth module.
• Underwater Islands wrecks (100-300 m): Wrecks in the underwater islands biome are a reliable source of Nuclear Reactor fragments.
• Sparse Reef wrecks (150-300 m): The sparse reef wrecks sometimes contain Nuclear Reactor fragments alongside other blueprint fragments.
• Grand Reef wrecks (200-500 m): Deeper wrecks here have fragments but require a depth-upgraded Seamoth.

Scan each fragment you find. Once you have scanned enough, the Nuclear Reactor blueprint unlocks in your habitat builder menu.

Materials Needed to Build the Nuclear Reactor

Once unlocked, build the Nuclear Reactor inside a multipurpose room using the habitat builder. The required materials are:

You also need a Bioreactor or other power source to fabricate the components if your base is not yet powered.

How to Craft Uranium Fuel Rods

The Nuclear Reactor needs uranium fuel rods to generate power. To craft fuel rods:

1. Mine Uraninite Crystals from the seabed in the grassy plateaus, underwater islands, and lost river. They glow green and are easy to spot.
2. Process Uraninite into Uranium at the fabricator.
3. Craft a Uranium Fuel Rod at the fabricator using multiple Uranium and a lead or titanium rod component.
4. Insert the fuel rod into one of the four slots on the Nuclear Reactor.

Each fuel rod lasts a very long time under normal load. With four rods, the reactor runs for extended periods without maintenance.

Power Output and Comparison

The Nuclear Reactor provides the highest consistent output at any location. For deep bases without a heat source, it is the only viable high-power option.

Tips and Best Practices

• Always keep a stockpile of Uraninite so you can craft replacement rods before they deplete.
• Pair the Nuclear Reactor with a Bioreactor or Thermal Plant as a backup for when rods run low.
• The reactor does not produce radiation outside the base, so it is safe to build near living areas.
• Only build a Nuclear Reactor if your base needs more than 500 W sustained; otherwise a Bioreactor or Solar is more cost-effective.
• Turn off non-essential modules (like the scanner room) when not in use to extend fuel rod life.