Even though it powers generators for 200 years and the only reason why the power armor only last 30 minutes with the power armor is because the power armor needs to power the hydraulics, headlamp, and the visor for your HUD in the power armor.

Laser weapons and power armor perhaps are just really inefficient. The player might be doing more damage to commonwealth than the worth of the combat delivered. Especially true if you side with the nuka raiders.
Just remember if you think thats bad the brotherhood ripped a generator from a town to get their blimp going. The institute take everything tech and uncertain how much tech is actually their own.

but you have to remember that when you remove the fusion core from the generator, nothing changes other than the generator light blinking a couple of times so it probably just acts as the starter for the generator.

Fallout lore states more or less that power armor was always something of an energy hog

difference is that the generator in powering lights not a weapon of war

core = low voltage DC
generator = uses low voltage DC to create higher voltage AC

tis true IRL as well

i always thought the fusion core acted as a kickstarter for the generator, and thus only needed activation. And thus didn't drain battery power.

Thats probably WHY the battery is so short, its been powering a building for 200 years for crying out loud!

nothing they powered nothing

Eh...already drained, and what exactly were they powering for that 200 years?