A B747-400 Captain was concerned that he was unable to deplane the passengers during maintenance activities that repeatedly plunged the cabin into darkness. Passengers agents were unwilling to comply with the request because of security issues.

Narrative

After returning to the gate following an aborted takeoff. The airplane started doing some very strange things. The auto speed brake motor started running; but no movement of the lever. I also noticed quite a few Status Messages. Basically the aircraft started load shedding (I think).It was then that I noticed the entire cabin was dark. I tried to manually turn on the emergency cabin lights and they would not turn on. The Mechanic then turned on the #1 and #4 hydraulic demand pumps and the normal cabin lights came on. The hydraulic synoptic showed everything normal; but it was anything but normal. This happened about four or five times and the Mechanics were as dumbfounded as we were.My concern is that after this happened a few times I was uncomfortable with the passengers being on a dark aircraft (it was after sunset); and I asked the agents to deplane. I was told we couldn't because of lack of security. The agents did not do as I asked; they simply waited me out. We were on the ground for about one hour; much of the time in the dark. I consider this to be a safety issue that could have escalated; had a Flight Attendant or an overactive passenger become uncomfortable with being in the dark. Please call with any questions.