A hydrogen fuel cell system generates electric power from hydrogen. Fuel cell electric vehicles (FCEV) have much smaller batteries than battery electric vehicles (at least by a factor of 10), as the energy is stored in the hydrogen. By exploiting the higher gravimetric energy density of hydrogen, FCEVs can offer a higher range than BEVs. However, their continuing deployment faces multiple technical and economic challenges, including safety of hydrogen handling (refuelling, residual leakage), on-board hydrogen storage (see the dedicated entry below) and the high cost of the fuel cell stack (the electrochemical reaction inside the stack requires a proton exchange membrane (PEM) coated with a platinum-based catalyst, a costly material) and system. Costs of the fuel cell stack and system are expected to decline significantly with economies of scale.
For FCEVs to be competitive with other powertrain technologies, hydrogen must be delivered to hydrogen refuelling stations at prices that bring per kilometre costs into the same range as conventional ICEs, or of battery electric vehicles powered by grid electricity. This will require further cost reductions in technologies for low- and zero-carbon hydrogen production technologies (e.g. SMR with CCS, renewable electricity generation such as wind and solar coupled to electrolysers), as well as in hydrogen transmission and distribution networks and in hydrogen refueling stations (HRS).