Fusion cores are used to power and activate suits of power armor. Each core provides roughly twenty minutes real time, (or approximately 10 hours game time) power armor use based on Action Points (AP) usage; actions such as holding breath when using scoped weapons, sprinting, utilizing V.A.T.S., or Jetpack modules causes the power to drain much faster, whereas walking consumes less power and remaining stationary drains none. Fusion cores have a total charge of 100.
The Gatling laser utilizes fusion cores as its ammunition, each core providing 500 shots. Nuclear Physicist can increase the amount of shots per core up to 1000, but the magazine capacity will remain at 500. Also combining with Repair bobblehead, the total amount of shots can be raised to 1100.
Fusion cores can also be ejected from power armor suits if one has the highest level Nuclear Physicist perk and no other explosive devices are currently equipped. Ejected cores land a short distance behind the user where they act as some sort of timed mine with a destructive force similar to that of a Fat Man's projectile. Note that contrary to the perk description, the cores cannot be actually thrown like regular grenades.
In addition to fixed locations below, fusion cores may also spawn in groups of four in certain ammo boxes across the Commonwealth. Cores can also be spawned in other container types by means of an eyebot pod, but only one at a time.
|ArcJet Systems||1||In the room where the Sole Survivor can restore power to the elevators|
|Atlantic Offices in the Glowing Sea||1||Atop the roof|
|Boston Airport||1||Spawns in the cargo area after Reunions|
|Boston mayoral shelter||1||In a room off the basketball court with a sign above it that reads "Restricted Area"|
|Cambridge Polymer Labs||1||One can be found in the office, either by picking the master lock or successfully finishing the laboratory's research|
|The Castle's armory||5||Including from Sarge sentry|
|Concord Civic Access||1||In a dark corner opposite the small drug cache that the mirelurk guards|
|fo4fh Crashed boat||1||Southwest of the Harbor Grand Hotel on the shoreline there will be a crashed ship with containers arranged to the side of the boat with flames trailing behind it. On the bottom floor there will be a Fusion generator with the fusion core|
|Erin Combes||1||Might give one for finding Ashes in the quest Here Kitty, Kitty|
|Finch farm||1||In the pumphouse across the river east of the farm. Pass code is written on the wall, below the door (0451)|
|Four Leaf fishpacking plant||3||Two inside (one of them behind a mag-lock door) and one on the roof of the building|
|Goodneighbor||2||On a shelf inside the train cart strongroom in during the quest The Big Dig|
|Greenetech Genetics||3||On the top floor, two behind a security door locked at master level, and one behind a door further on locked at advanced level|
|Gunners plaza||3||2-3 behind a novice locked door in a room on the opposite side of the elevator on the roof. One other one can be found on the center of the roof behind a door with a generator, running the fusion core|
|Near Jamaica Plain||1||On the floor in a house on the outskirts of Jamaica Plain, on the floor next to a dead feral ghoul|
|Kendall Hospital||1||In the basement|
|Longneck Lukowski's Cannery||1||In the basement area after the sewer section; be careful of mines|
|Malden Center||3||All near the generator after descending in the elevator. One is one the ground in front of the generator. The other is in the cardboard box on the table to the left|
|Malden drainage||1||At the end of the canal just north of the Taffington boathouse|
|Milton parking garage||4||A part of one possible reward for completing the trap-ridden maze inside the parking garage|
|Mass Fusion containment shed||1||Behind a mag-locked door (unlocked via terminal right above it). The area is heavily irradiated|
|Medford Memorial Hospital||1||West on the second floor in a generator room.|
|Fallout 4 merchants||1||Any merchant who stocks ammo will most likely carry up to 5 at 100% charge, and may carry one or two others at lesser charge (usually 40%-90%)|
|Museum of Freedom||1||Lowest floor behind a security door (Novice terminal). Sturges asks the player character to retrieve it during When Freedom Calls|
|Mystic Pines||1||In the basement. The door to the basement is locked (Advanced) and requires 1 point in the Locksmith perk to pick|
|Poseidon Reservoir||1||On the main road at a military checkpoint north of the reservoir, in a power armor|
|The Prydwen's maintenance bay||2||Can be stolen off suits on The Prydwen by sneaking behind them (Paladin Danse will disapprove)|
|Quincy ruins church||1|
|Railroad HQ escape tunnel||1||Near the exit behind a security gate that can be opened from the Expert terminal to the left of the door|
|Railroad's old HQ under Slocum's Joe||1||The fusion core is best accessible from the escape tunnel|
|Recon Bunker Theta||1||Can be found during The Lost Patrol|
|Red Rocket truck stop||1||Mole rat den|
|Revere Beach station||1||Obtained for returning an Overdue book at the arcade building near the the station for fifty tokens|
|Roadside Pines motel||1||Behind the motel on the west side of the building.|
|Robert Joseph MacCready||1||As an active companion, he will frequently provide fusion cores in lieu of ammunition if he is equipped with a set of Power armor.|
|Robotics disposal ground||3||In chest near the robot in the center of the Two more can be retrieved from the robot by enabling it and then self-destructing it|
|South Boston military checkpoint||1||In a power relay under the elevated freeway just east of the checkpoint|
|Starlight Drive In||1||In the building behind the screen, with a locked (Novice) door.|
|Suffolk County charter school||1||In a generator in the basement|
|Super Duper Mart||1||In the generator room in the back|
|USAF Satellite Station Olivia||1||In the main center room in with the generator and the catwalk. Generator emits a buzzing sound.|
|Vitale pumphouse||1||In the second room, requires combination "10-4-5-1" to access.|
|Walden Pond gift shop||2||In a suitcase during the mission where one fights a group of raiders to liberate a village|
|Waystation||1||When following Dogmeat during the Reunions quest|
|Weston water treatment plant||1||In the eastern hut|
|Wilson Atomatoys factory||1||Southern side|
|Wreck of the FMS Northern Star||1||Inside a generator on the ground level, near the bow of the ship|
|Yangtze||1||Inside an open footlocker in the crew quarters|
|fo4fh The Nucleus||2||On the metal shelves in the first wooden shack after the Decontamination Arches|
|fo4fh Glowing Grove||1||On one of the tables|
- All sentry bots encountered in the game carry 2 or more fully charged fusion cores.
- The item's value is independent of its charge level, however drained cores are discarded and cannot be sold. This is a helpful way of gaining caps if remembering to transfer cores before they are discarded. The player character can use a fusion core almost completely (even so the charge reads 0/100), and sell it for roughly 120-180 caps as long as it is still in their inventory.
- This item can be found in containers like other ammo, but is much less common.
- While in power armor, besides the current fusion power level, the players can see how many fusion cores are available in their inventory. If 100 or more cores are available, the counter will top out at 99 as it only has two digits.
- A suit of power armor doesn't need a fusion core in it for a Companion to enter it. If a fusion core happens to be in a companion's power armor, it does not drain from use.
- Fast Traveling does not drain energy from fusion cores while wearing power armor.
- Using the jetpack drains the core's power much faster than any other type of armor operation.
- Because of the fact that fusion cores are used as ammunition for the Gatling laser the scrounger perk allows to find them at an increased rate.[verification overdue]
- Fusion cores glow when they suffer critical damage and eventually erupt in a small, but powerful nuclear detonation.
- Leaving a fusion core in a power armor parked in a settlement will very often result in a settler, companion or even an invader wearing the power armor. And while the core will not drain, there may be some very undesired consequences. Such as, power armor being destroyed in combat, named settlers not having a dialogue option to ask them to exit the armor and therefore making it not usable by the player, or the power armor being discarded somewhere in a large settlement making it hard to locate.
- Fusion cores at different charge levels do not stack together.
- Fusion cores have the same hit chance as the NPC's torso in V.A.T.S. (assuming player is at the backside of them).
- ps4 xboxone Completely draining a fusion core while in power armor and having a weapon not be fully loaded at the time may cause the game to show that the player character has no ammo for said weapon. Solution: Unequip and re-equip the weapon.[verified]
- ps4 xboxone pc Having multiple fusion cores at the same level the power armor had when the Sole Survivor stepped into it may result in them all draining with the one in the power armor.[verified]
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