The energy grid is a mechanism found at the entrance to the Powerworks. It is the first thing Samus sees when she enters the Powerworks in search of "ancient Chozo artifacts". The grid is vaguely brain-like and lights up when Samus steps inside the Powerworks. The grid is offline, and must have power restored to it by hitting the four power nodes surrounding it with five simultaneously fired Missiles.
The nodes connect to the grid through channels in the wall that coalesce into a trio. When she has activated the nodes, they will light up and spin in place, the grid will flash, and a small entry lock at its base will open. Samus can enter this in Morph Ball form to reach the lower part of the Powerworks.
As with the room itself, the grid was designed by Matt Manchester.
"Energy grid currently offline. Activation of surrounding nodes will restore grid power."