1.2 kgs of hydrogen on 100 kms in the European consumption cycle. However, hydrogen is very full energy with 33.3 kWh per kg. There are about 40 kWh on 100 kms.
One of the possibilities for the hydrogen production is the electrolysis. Afterwards the fuel must go in the tank. Regardless the pressure tank with 700 bar or the liquid tank with-254 degrees, to bring the fuel in the tank requires a substantial amount in energy. Cool on-254 degrees needs about 1/3 of the energy stored in the hydrogen. 700 bar excess pressure, there is also a study for cars with pressure air engine. They simple drive with the air put into the pressure tank.
70 kWh on 100 kms with solar energy
A square meters photovoltaic delivers in Germany a little bit more than 100 kWh per year. Turning after the sun, this increases on a little bit more than 130 kWh. Therefore a square meters of sun tracked Photovoltaic in Germany delivers possibly energy for 185 kms with the fuel cell Opel Zafira. On an average 15,000 kms per year signify about 81 ms ² tracked Photovoltaic.
Already in 1991 the PEGE propagated inhabitable solar power plants producing enough electric power for heating and war water by heat pump, electric power usage of the inhabitantgs and fuel for cars.