Ok so there are 2 panels underneath the platform ( I do not understand why I was unable to see the 2nd one before ). The 2nd panel DOES indeed kill the flow of electricity to the platform floor above and you will now be able to access the control panel above which drops the red laser fields ahead. Defeat the enemies ahead and then defeat Stangg and click on the control panel afterwards and you are done.
Once you have stepped on the floor panels with the debris and taken out the panels above, move to the end of the field. Just to the left of this is the generator that will shut down the whole thing.