Researchers at UC Davis developed “Spatial Transportation Infrastructure, Energy, Vehicles, and Emissions (STIEVE),” an optimization model for hydrogen refueling stations in California. The model uses inputs from the California Statewide Travel Demand Model (CSTDM) and other sources to determine heavy-duty vehicle travel demand across the state, and the corresponding, localized energy demand. The model then determines which of the transportation analysis zones (areas based on census geography used to replicate areas of trip origins and destinations) delineated by the CSTDM are optimal areas for refueling stations and the number of stations needed in each zone to meet demand while minimizing costs. The final step is a suitability analysis that identifies each station’s specific location within a designated transportation analysis zone, based on a determined footprint for the refueling station.