This is something that was just offhandedly mentioned in a Sci-Fi book I read once and as I am now writing one myself I thought I might use it.
The scenario is that I have a ship approaching a warp gate and am describing the appearance and mechanics of the gate. The idea is that warp drive research on Earth ended in a dead end because we were never able to effectively produce enough energy to power a warp field larger than the ship and generator itself.
Jump to 400 hundred years in the future and humanity has colonized a few other star systems by means of sub-light, generation ships. They then develop a functioning warp bridge, rather than a ship drive, by building massive warp field generators on each end.
The generator stations, basically warp gates for simplicity, generate the necessary energy over several days, and then expend it all in a single day or a few hours (undecided) to power the warp field.
Would massive flywheels be a valid form of energy storage? If not, what other ideas of energy storage might be more reasonable?
I would like to clarify that this is the heaviest handwavium in my entire story. Besides the completion of warp theory, functioning cryogenics, fusion drive technology, and some advances in material science, the story is supposed to be as reasonably realistic as I can get. Real physics. No artificial gravity. Space travel takes days and weeks between planets in-system. The warp gates are posted at the far edge of a solar system, allowing instantaneous travel between systems, but once exiting the gate traveling in-system is much slower again.
Addendum: I should have included that I am imagining two flywheels in a pair on opposite sides of the station to counteract one another, as many of you have mentioned that would be necessary.