Method and system for controlling oxygen delivery to a cell implant. In one embodiment, the system includes a water electrolyzer, a cell capsule, a gas conduit, a total fluid pressure sensor, and a controller. The water electrolyzer generates gaseous oxygen with a variable output. The cell capsule includes a cell chamber adapted to hold cells. The gas conduit interconnects the water electrolyzer and the cell capsule to deliver gaseous oxygen generated by the water electrolyzer to the cell capsule. The total fluid pressure sensor is positioned at a location that provides a representative reading of the total fluid pressure within the cell chamber. The controller is electrically coupled both to the total fluid pressure sensor and to the water electrolyzer so that the controller may control the variable output of the water electrolyzer based on one or more sensed total pressure readings from the total fluid pressure sensor.
