Why in news?

• Germany on Monday rolled out the world’s first hydrogen-powered train, signalling the start of a push to challenge the might of polluting diesel trains with costlier but eco-friendly technology.

Background:

• Hydrogen trains are equipped with fuel cells that produce electricity through a combination of hydrogen and oxygen, a process that leaves steam and water as the only emissions.
• Excess energy is stored in ion lithium batteries on board the train.
• The Coradia iLint trains can run for around 1,000 km on a single tank of hydrogen, similar to the range of diesel trains. Alstom is betting on the technology as a greener, quieter alternative to diesel on non-electrified railway lines — an attractive prospect to many German cities scrambling to combat air pollution.
• Two bright blue Coradia iLint trains, built by French TGV-maker Alstom, began running a 100 km (62-mile) route between the towns and cities of Cuxhaven, Bremerhaven, Bremervoerde and Buxtehude in northern Germany — a stretch normally plied by diesel trains.
• Alstom has said it plans to deliver another 14 of the zero-emissions trains to Lower Saxony by 2021, with other German States also expressing an interest.

Advantages of hydrogen fuel:

• It’s a renewable energy source and bountiful in supply
• It practically a clean energy source
• Hydrogen energy is non-toxic
• It’s far more efficient than other sources of energy
• Used for powering space ships

Disadvantages of hydrogen fuel:

• Hydrogen energy is expensive
• Storage complications
• Tricky to move around
• It is highly flammable
• It is not easy to replace existing infrastructure.