I really hate this achievement. Either we don't get the EMPs (3 times out of 30-40 tries) or all four of us suck big time (we failed all three times).
The main problem is, we only get him to spawn in wave 7/8/9/10, early does simply not work for us, despite the strom above.
When he's there, he or the other zombies destroy the turbines or we get overrun from both sides because avoiding his electricution, reviving teammates + concentrating on him when he is in the middle is do much at once.
If the turbines are destroyed during the fight with the electric guy, is it possible to pick two new ones from the work bench at the bus stop and place them at the pylon?