Yeah, getting the challenge to frustration ratio might have gone a bit wrong on this one! :)
There's a pickup in the level that goes with the broken power box, but only when the power is off (other wise you get electrocuted!) , and there's no active fire (that's a one time event btw) - then reconnect power to green ( they'll be a green light at the end of the tunnel too)
I actually made the conscious decision to keep the UI clear of prompts too! Lesson learnt :)
Hope you don't mind the mild spoilers, but our time is precious, and there's nothing worse than a 'frustrating' game loop!