The safe reactors I made so far only output 100 EU/t (effectively). And running a reactor with ice or as a Mark III or IV is no option for me, since I dont want to blow up my facilities on my server.
Spamming solar panels also isnt a solution (server load). One good way could be to find a way to pump lava from the nether to geothermal generators in the normal world, without requirering someone to stay in the nether 
The fusion energy would be a nice next tier in energy production, if implemented in a similar way like the nuclear reactor.
i'm pretty sure i made a safe reactor that output more then that, it could output a total of 28,million EUs using 6 cells and would require a cooldown period but was safe, so i ran 4 Reactors and rotated them so that i always had 2 running.
also ice reactors are always an "option" you just don;t want to risk it
you can easier make a reactor with 2 collumns of ice blocks and the rest a properly set up reactor and just come by and refil the ice every 30 minutes to an hour for ALOT more EU output. or if you have a mod that has pipes like BC then you can do what i call a "Coolant Overflow" system where you send way more ice through pipes then would ever be needed to cool your reacter and have the excess go back to boxes. that way it's 100% safe and have back up safety messures.
if you need more energy it's way more effective to make an addition reactor then 180+ solar panels. not to mention it's alot less strain on the server. also! an idea i had with reactors is to run like 12 of them that would output about 500EU/t and set them up on a really slow Redstone Clock that circles around turning the reactors on and off, this would allow me to control them and keep 1 or 2 of them on in rotation at ALL times, basically this would turn them on and off at a ratio of 1:6 or 1:12, that way i could make them all provide power to my house effectively and stay cool without exploding, not to mention this would basically allow them to keep charging my house for 12 or 24 hours before needing to be refilled.