Generator ( Fallout 4 ) Generators are settlement objects in " Fallout 4 " and its add - ons " Vault - Tec Workshop " and " Wasteland Workshop " . Generators are used to produce power in a settlement . Characteristics . Generators are required to produce electricity for settlements . Once a generator has been constructed it is necessary to connect it with copper wires to a power grid to harness its power . The power can then be used to power other settlement objects such as lights , turrets , water purifiers and other utilities . The base game includes 4 types of generators ; 3 other types are added through add - ons . Windmill . This generator is silent but is noticeably more expensive in the power - to - cost ratio . Small , medium and large generators . Those noisy generators appear to produce power through the combustion of some sort of fuel . They are the cheapest source of electricity for settlements of small and average size . The small and medium generators are the only generators to easily fit inside regular wooden structures . Fusion reactor . This reactor was introduced by the " Wasteland Workshop " add - on . It is an almost completely silent power source . It provides 100 units of power , 10 times as much as the large generator , its closest contender . The fusion generator is a fusion powered electric generator , that uses a fusion core to produce electricity . Its appearance and animations are identical to the fusion generators found throughout the Commonwealth . Despite this , it is not possible to have the generator interact with fusion cores in any way , neither for recharging cores nor slotting them in as additional power source . Unlike the fusion generators found around the wasteland , player built fusion generators do not have the light above the main control panel . Fusion generators can be shut down and powered back up by pressing upon the fusion core in the main panel . Vault - Tec reactor . This reactor was introduced by the " Vault - Tec Workshop " add - on . The production of this virtually silent reactor represents a 50 % increase over the fusion generator . However , it requires more resources and is extremely bulky . The Vault Tec reactor is also has unique ability to power floors and walls that has direct connection to it even without cables . The power can be used by attaching an electrical outlet on the connected wall . Despite its appearance , the reactor ' s underside which looks like part of the flooring is vulnerable to damage from under it , so you may want to avoid using the reactor ' s underside as a ceiling in places which may be attacked by enemies . Vault - Tec super - reactor . This reactor was introduced by the " Vault - Tec Workshop " add - on . The Vault - Tec super - reactor greatly surpasses the fusion generator as the greatest source of energy available . It is virtually silent as well ; these advantages come at a cost , however . The reactor takes up a large amount of space and requires many parts to build . Even though the Vault - Tec super reactor gives 5 times more power than the fusion generator , it costs 8 . 3 times more nuclear material to build . Like its smaller variant , it has the ability to send power through floors and walls of the vault variant of materials . Likewise , the reactor ' s underside ' floor ' is vulnerable to damage which can knock the reactor out if hit enough times .