Can you please add beacons without modules to your list? I just realized that the beacons I laid down with my blueprints are sucking up three times as much power as my assemblers when I'm not even producing modules yet.

It's your choice how to play of course, but it's waaay too cheaty: this is the only power consumption that beacon have at all.
And... Of course, having beacons are always very power consuming - and that's for reason - they transfer effects.
There is no way in Factorio API to make beacons consume power only when there are working factories.

So the only thing I've done is just disabling Beacon energy usage entirely - added to 3.1.0

Perhaps I didn't communicate clearly. I don't want to completely disable beacon power usage at all times, only disable it when they don't contain any modules. After all, a beacon without modules isn't actually doing anything, so why should it be sucking back power as if it weren't completely idle?

This mod only works with prototypes at loading stage of game, thus it have zero impact to performance of game.

But because of Factorio API your request can only be done in runtime (by basically replacing Beacon with something looking like Beacon but in fact being something else, and then replacing it back when modules are inserted).
This will affect runtime end even more problem to me - it will overcomplicate things and might have bugs - so I don't want to do that, sorry.

Ah. Fair enough. Thank you for your efforts.