Hydrogen vs. Battery Buses: A European Transit Reality Check

Battery Bus Infrastructure & Operations

• Several comments argue battery buses are operationally simpler: depots “just” need higher-capacity electrical feeds and chargers, often with managed charging to stay within grid limits.
• Others counter that depot loads (e.g., 50 buses × 300 kW) imply multi‑MW connections, often beyond existing low‑voltage capacity, especially in the UK, with long delays for grid reinforcement.
• Mitigations suggested:
  • Smaller chargers and longer dwell times (overnight, mid‑day, at route termini).
  • Split shifts and mid‑day charging aligned with solar output.
  • On‑route fast or overhead charging to reduce required battery size.
• Critics say such schemes reduce operational flexibility and complicate planning if buses return late or can’t reliably access on‑route chargers.

Hydrogen Buses: Pros, Cons, and Motives

• Many see little role for hydrogen in buses: need for entirely new fuel infrastructure, air handling and filtration for fuel cells, storage losses, compression/boil‑off issues, and ~3× worse electricity‑to‑wheel efficiency than batteries.
• Proponents highlight:
  • Faster refueling and higher gravimetric energy density, helpful for heavy or long‑range vehicles.
  • Familiarity for OEMs and suppliers used to ICE architectures.
  • Pilot fleets in places like Cologne and Hamburg, sometimes tied to broader “hydrogen hub” strategies.
• Strong skepticism that hydrogen will ever be cost‑competitive for road vehicles; several note current hydrogen is overwhelmingly from steam‑methane reforming, so not low‑carbon.
• A recurring theme is that hydrogen hype is driven by fossil fuel and legacy automotive interests to preserve existing value chains.

Trolleybuses and Hybrid Approaches

• Battery‑equipped trolleybuses are repeatedly praised as a “best of both worlds”: overhead wires on main corridors plus batteries for extensions, detours, and workarounds.
• Examples from Central Europe and elsewhere show automatic pole stow/deploy, reduced need for massive depot chargers, and operational resilience during roadworks.
• Counterpoint: overhead wiring is capital‑intensive, tricky to maintain (especially complex junctions/roundabouts), and most cities are choosing pure BEV buses instead.

Efficiency, Cost, and Energy Sources

• Multiple threads emphasize that, with clean electricity, efficiency directly matters: BEVs are seen as roughly 2–3× more energy‑efficient than hydrogen vehicles end‑to‑end.
• Hydrogen is broadly viewed as better reserved for industrial feedstocks (fertilizer, steel), some grid storage, and possibly ships/aviation, not city buses.
• Diesel‑electric hybrids are acknowledged as an important transitional technology, but in many cities new purchases are shifting entirely to battery buses.

Other Notes

• Concerns raised about battery bus weight and road wear, though some report similar weights to diesel buses.
• Biogas/methane buses and overhead‑wired trains are mentioned as additional, often better‑proven, decarbonization options.