I think Adam is right...
"In electric power steering an electric motor drives the steering-mechanism. The motor is attached to the steering rack, and a microprocessor regulates the motor and so the steering dynamics. The key component is a sensor on input shaft which converts steering torque and rotation speed into signals to be fed into the microprocessor. Electric power systems have the 1-MPG advantage compared to the hydraulic system’s fuel efficiency, which includes a pump that is constantly working. The criticism is that they do not provide enough feedback to the driver."
....unless its Servotronic, which I'm not sure about....