The average cost for hydrogen fuel is right around $16.50 per kilogram, but this can vary with supply and demand, as well as where you refuel. Currently, only California and Hawaii have hydrogen refueling stations, with about 45 stations in these two states combined.
However, you get a little something extra for your money. Hydrogen fuel cell cars get around 70 MPGe, and cars carry between 5kg and 6kg, resulting in about 350 to 400 miles per tank. At its current prices, hydrogen fuel cells aren’t necessarily economical, but as technology advances, it should improve the efficiency of a hydrogen engine.