Gray Hydrogen, High Costs, and the Real Emissions of SunLine’s Fuel Cell Fleet
Why it matters: SunLine's experience reveals the immense cost and persistent immaturity of hydrogen transit technology.
- SunLine Transit Agency has dedicated 25 years to making hydrogen buses work, cycling through various electrolyzers, reformers, and vehicle types since 2000.
- The agency's hydrogen fueling system has undergone four distinct generations of development, from early pilot electrolyzers to a new liquid hydrogen station commissioned in 2024, indicating a continuous need for upgrades due to insufficiency or unreliability.
- An estimated $27 million (in 2026 dollars) has been invested in SunLine's refueling system, underscoring the significant capital expenditure required to maintain and evolve hydrogen infrastructure.
SunLine Transit Agency, a long-time proponent of hydrogen buses, has spent a quarter-century and an estimated $27 million repeatedly rebuilding its hydrogen fueling infrastructure, revealing a pattern of successive projects rather than a stable, mature operating model. Despite continuous upgrades and a willingness to innovate, the agency's experience highlights the persistent challenges and high costs associated with making hydrogen transit viable.
