A mobile hydrogen dispenser for at least partially filling a hydrogen tank of a fuel cell-powered vehicle, said dispenser comprising: a first supply line (SL 1) having upstream and downstream ends, the upstream end of the first supply line being adapted and configured to receive a flow of hydrogen from a hydrogen source; a delivery line having upstream and downstream ends, a nozzle fluidly communicating with the downstream end of the delivery line that is adapted and configured to engage with an opening of a fuel tank of a fuel cell vehicle; characterized in that said dispenser comprises a first orifice plate (OP 1) disposed in the first supply line; a backpressure regulator disposed at the downstream end of the first supply line (SL 1), the backpressure regulator being a dome-loaded or spring-and-dome loaded backpressure regulator that is adapted and configured to maintain a pressure of gas in said first supply line between said orifice plate and said backpressure regulator at or below a variable set point pressure of the backpressure regulator, the variable set point pressure being set by a pressure in a dome of the backpressure regulator; the upstream end being of the delivery line being adapted and configured to receive a flow of hydrogen from the backpressure regulator, the downstream end of the delivery line being adapted and configured to direct the received flow of hydrogen to a hydrogen tank of a fuel cell-powered vehicle; a reference pressure line having an upstream end and a downstream end, the upstream end of the reference pressure line being adapted and configured to receive a flow of hydrogen from the hydrogen source; a differential pressure regulator having an inlet and an outlet, the inlet of the differential pressure regulator being in flow communication with the downstream end of the reference pressure line; and a first pilot line in flow communication between the differential pressure regulator and the dome of the back pressure regulator, the differential pressure regulator being adapted and configured to maintain a constant pressure differential ΔP between a pressure of hydrogen in the reference pressure line and a pressure of hydrogen in the first pilot line. a first supply line (SL 1) having upstream and downstream ends, the upstream end of the first supply line being adapted and configured to receive a flow of hydrogen from a hydrogen source; a delivery line having upstream and downstream ends, a nozzle fluidly communicating with the downstream end of the delivery line that is adapted and configured to engage with an opening of a fuel tank of a fuel cell vehicle; characterized in that said dispenser comprises a first orifice plate (OP 1) disposed in the first supply line; a backpressure regulator disposed at the downstream end of the first supply line (SL 1), the backpressure regulator being a dome-loaded or spring-and-dome loaded backpressure regulator that is adapted and configured to maintain a pressure of gas in said first supply line between said orifice plate and said backpressure regulator at or below a variable set point pressure of the backpressure regulator, the variable set point pressure being set by a pressure in a dome of the backpressure regulator; the upstream end being of the delivery line being adapted and configured to receive a flow of hydrogen from the backpressure regulator, the downstream end of the delivery line being adapted and configured to direct the received flow of hydrogen to a hydrogen tank of a fuel cell-powered vehicle; a reference pressure line having an upstream end and a downstream end, the upstream end of the reference pressure line being adapted and configured to receive a flow of hydrogen from the hydrogen source; a differential pressure regulator having an inlet and an outlet, the inlet of the differential pressure regulator being in flow communication with the downstream end of the reference pressure line; and a first pilot line in flow communication between the differential pressure regulator and the dome of the back pressure regulator, the differential pressure regulator being adapted and configured to maintain a constant pressure differential ΔP between a pressure of hydrogen in the reference pressure line and a pressure of hydrogen in the first pilot line.