Ann: CDP Achieves Over 36 Hours Of Continuous Hot Operation, page-65

Germany commercially operates hydrogen-powered trains, while the US, the UK, France, and Japan are in the testing phase.Add Sth Korea to that list too. India's plan to develop the technology involves retrofitment of hydrogen fuel cells on diesel electric multiple unit (DEMU) rakes.

Thanks. Currently the main drawback is the hydrogen generation. SMA hydrogen from fossil fuel is subject to fugitive emissions, is a finite resource and therefore not sustainable as well as creating huge amounts of CO2. Hydrogen via electrolysis takes more energy to make than the energy derived from the hydrogen it creates. But hardly anyone talks about turquoise hydrogen. If the Hazer process delivers to expectations, hydrogen transport should be way more viable than it is at present.