NOVELTY - The production of hydrogen gas for reforming a feedstock (23) using plasma reformation, comprises supplying a hydrocarbon liquid and gas to a pair of spatially separated electrodes (15, 16) defining a gap (26) between the pair of electrodes, applying a voltage across the pair of electrodes to induce an electrical arc in the gap, dynamically adjusting the spatial separation of the electrodes to change the length of the gap to control parameter of the plasma, and increasing and decreasing the gap length.    USE - Useful for reforming a feedstock using plasma reformation.    ADVANTAGE - The method is efficiently producing a high purity stream of hydrogen, and a useable carbon product.    DETAILED DESCRIPTION - The production of hydrogen gas for reforming a feedstock (23) using plasma reformation, comprises supplying a hydrocarbon liquid and gas to a pair of spatially separated electrodes (15, 16) defining a gap (26) between the pair of electrodes, applying a voltage across the pair of electrodes to induce an electrical arc in the gap, dynamically adjusting the spatial separation of the electrodes to change the length of the gap to control parameter of the plasma, increasing and decreasing the gap length to increase and decrease the voltage between the pair of electrodes resulting in an increase and decrease of the plasma size and the hydrogen gas production rate respectively, maintaining a constant electrical current flow between the pair of electrodes, rotating the negative polarity electrode during the step of generating hydrogen gas, periodically reversing the polarity of the electrodes, controlling the level of the hydrocarbon liquid relative to the pair of electrodes, and adding a chemical compound into the hydrocarbon liquid to increase production of a desired solid product. The electrical arc contacts the hydrocarbon to form a plasma and produce a gaseous product comprising hydrogen gas and a solid product comprising carbon. The rotation of the electrodes reduces adherence of the solid product to the pair of electrodes, and does not change the gap length. The periodic reversing of the electrode polarity reduces adherence of the solid product to the pair of electrodes. The gap length is dynamically adjustable of 0.1-51 mm. The pair of electrodes is generally horizontally and vertically spaced. The electrodes are fully above the level of the hydrocarbon liquid that comprises two hydrocarbon feedstocks. The chemical compound comprises a metal atom. The metal compound comprises two chemical compounds. The voltage differential across the electrodes of 30-50 V, and a current flow between the electrodes of 5 mA-150 A. An essentially anaerobic atmosphere is placed over the hydrocarbon fluid. The method further comprises removing dissolved or entrained oxygen from the hydrocarbon liquid prior to supplying the hydrocarbon liquid into the gap, circulating the liquid hydrocarbon through a solids separation device, separating the solid carbon product suspended in the circulating liquid hydrocarbon, controlling the flow of hydrogen gas out of a chamber (11) surrounding the pair of electrodes to obtain a desired pressure within the chamber, and separating out the solid carbon from the hydrogen gas by electrostatic precipitation. The chemical compound is an organometallic compound, which is a metal-containing organic or inorganic salt. The gaseous product produced comprises hydrogen gas at greater than 95 vol.% of hydrogen.    DESCRIPTION OF DRAWING(S) - The diagram shows a plasma reformer.    Reactor chamber (11)    Electrodes (15, 16)    Feedstock (23)    Gap (26)    Variable speed motor. (31)