An EPS grid or plasma grid was a component of the electro-plasma distribution network on Starfleet vessels from the 22nd century onwards. In the event of an emergency, the grid may be shut down to avoid an overload. By the 24th century maintenance was performed on the grid at regular intervals. In 2151, Lieutenant Malcolm Reed bypassed the EPS grid to receive power from Enterprise NX-01's impulse drive to get the phase cannon online, Trip Tucker denied this possibility, but later allowed it. (ENT: "Silent Enemy")