Hydrogen refueling infrastructure deployment to support California's advanced clean fleets regulation

The California Air Resources Board's Advanced Clean Fleets (ACF) regulation requires covered fleets to transition to zero-emission vehicles by 2042. This study develops the Integrating Market Penetration and Cost Technologies (IMPACT) framework to jointly model vehicle cost, technology adoption, and hydrogen-refueling infrastructure for California's medium- and heavy-duty fleet through 2050. In a hydrogen-forward scenario, fuel-cell electric trucks (FCETs) become a material pathway when fuel-cell system costs, including a 35% markup, fall below $100/kW and retail hydrogen prices reach $6/kg. Under the hydrogen-forward scenario, the simulated FCET stock reaches approximately 799,000 vehicles by 2050, with FCETs accounting for55–60% of new medium- and heavy-duty truck sales. This fleet requires 1040 high-throughput stations, 5900 metric tons of hydrogen per day, and $9.9 billion in cumulative station capital investment ($9.5 million per two-dispenser station). These results illustrate the infrastructure scale and cost conditions associated with substantial FCET deployment in the scenarios examined.