(not the immibis IC2 classic)
How to reproduce the problem: Set up a laser array for a fusion reactor w/ laser amplifiers and ultimate cable. Add creative energy cube to cause crash.
edit: doesn't crash with Thermal expansion's creative energy cell or with an ultimate energy cube in the same place.

Crash report:
crash-2016-05-22_11.05.24-server.txt

Should be fixed, I was apparently emitting a value too high to be supported by other energy networks.