Introduction: Beyond the Passenger Car
While battery electric vehicles (BEVs) have largely won the race for small passenger cars, the “heavy lifting” of the global economy—trucking, shipping, and flying—presents a massive challenge. This is where hydrogen steps in.
Because hydrogen has a higher energy density and faster refueling times than batteries, it is the leading contender for decarbonizing the most difficult parts of the transport sector.
1. Road Transport: The Heavy-Duty Champion
For 40-ton trucks and public buses, weight and downtime are the enemies of profit.
The Fuel Cell Advantage: Hydrogen Fuel Cell Electric Vehicles (FCEVs) can travel 350 to 400 miles on a single tank and refuel in just 3–5 minutes, similar to diesel.
Weight Efficiency: Unlike BEV trucks that require massive, multi-ton batteries that eat into cargo space, hydrogen tanks are relatively lightweight.
Current Status: Thousands of hydrogen buses and trucks are already on the road today in cities like London and across regions in Asia and Europe.
2. Maritime: Navigating the High Seas
Shipping is responsible for about 3% of global greenhouse gas emissions. Because deep-sea ships require immense power for weeks at a time, batteries are often physically impossible for these routes.
Short-Sea Shipping: Ferries and coastal vessels are already adopting hydrogen fuel cells. For example, the MF Hydra in Norway became the world’s first ferry to run on liquid hydrogen in 2021.
Ocean-Going Vessels: For long-haul shipping, hydrogen is often converted into Ammonia or Methanol, which are easier to store in large volumes on ships.
3. Aviation: Can Planes Fly on Green Hydrogen?
Aviation is perhaps the hardest sector to clean up. Hydrogen offers two distinct paths for the skies:
Direct Combustion: Hydrogen can be burned directly in modified jet engines. This provides the high thrust needed for large aircraft but produces some nitrogen oxides ($NO_x$).
Fuel Cells: Hydrogen is converted to electricity to power propellers. This is zero-emission (only water vapor) and highly efficient, making it ideal for short-to-medium haul flights.
Major Players: Airbus has committed to bringing a hydrogen-powered commercial aircraft to market by 2035.
4. Rail: Electrification Without the Wires
While many trains run on overhead electric lines, thousands of miles of track remain un-electrified because the infrastructure is too expensive to build.
The Alternative: Hydrogen trains (like the Alstom Coradia iLint) can run on existing non-electrified tracks, replacing dirty diesel engines with quiet, zero-emission technology.
Benefits: They offer a “two-mode” capability, running on battery/overhead power where available and switching to hydrogen for the rest of the journey.
5. Hydrogen Engines vs. Fuel Cells
There are two ways a vehicle “uses” hydrogen:
Fuel Cells: Generate electricity through a chemical reaction. They are silent and 2-3 times more efficient than traditional engines.
Internal Combustion (H2 ICE): Burn hydrogen like gasoline. These are cheaper to manufacture and more tolerant of “lower-grade” hydrogen, but they are less efficient than fuel cells.
Conclusion
Hydrogen isn’t competing with batteries; it’s complementing them. While batteries handle our daily commutes, hydrogen will likely power the trucks that deliver our goods, the ships that cross our oceans, and the planes that take us abroad.
Next Up: We’ve covered the “what” and “how.” Now, let’s talk about the “where.” In Article 10, we explore: What infrastructure is needed to support a hydrogen-based economy?