A 'supplemental' Hydrogen system enhances the efficiency of the petrol or diesel in your vehicle. Use of this system is not an attempt to run your vehicle on Hydrogen gas exclusively. Instead, it is a way to more efficiently burn the fuel that you are already using. By fully atomising the fuel molecules and burning them as a vapour (instead of the larger droplets that they would normally be).
So, by using a supplemental Hydrogen system, we are simply taking a vehicle that’s compromised and inefficient and bringing it up to a higher level of efficient combustion.