© SamTrans
San Mateo County Transit District (SamTrans) has contracted Fastech and Bosch Rexroth to construct what the two companies describe as the world’s largest hydrogen refueling station dedicated to transit buses, capable of dispensing up to 3.5 tons of hydrogen per day to a fleet of up to 175 fuel cell electric buses (FCEBs) in California.
A Market Defined by Small-Scale Infrastructure
The project arrives at a moment of acute fragility in California’s hydrogen refuelling network. Supply disruptions in early 2025 left just six stations operational across the state, exposing the vulnerability of a network historically dependent on gaseous hydrogen logistics. The SamTrans facility, by contrast, will handle liquid hydrogen (LH2) — a format that offers higher energy density but introduces its own challenges around boil-off, efficiency losses, and infrastructure complexity.
The scale of the planned station is notable. According to analyst firm Interact Analysis, nearly three-quarters of the roughly 1,160 hydrogen stations operating worldwide in early 2025 dispensed no more than 500 kg per day. China’s Xuanli station in Xinjiang — currently among the largest in existence — handles 10 tons daily, but serves heavy-duty trucking rather than urban transit.
CryoPump Technology Makes Its Commercial Debut
At the core of the station will be the first commercial deployment of Bosch Rexroth’s CryoPump, a liquid hydrogen pumping system first exhibited at Hannover Messe in 2024. Developed in collaboration with FirstElement Fuel, the largest commercial hydrogen station operator in the United States, the technology uses a two-stage electro-hydraulic pump capable of handling both liquid and gaseous hydrogen. The design eliminates buffer gas storage tanks and complex valve manifolding — infrastructure that has historically driven up both the cost and physical footprint of large-scale hydrogen stations.
Bosch Rexroth says the system achieves efficiency above 95%, extends maintenance intervals beyond 4,000 hours — roughly four times the conventional benchmark for crankshaft-based pumps — and requires less than 11 square metres of space. The company claims operating cost reductions of up to 70% compared with conventional compression setups, and says the technology nearly eliminates hydrogen losses from boil-off and venting during the liquid-to-compressed gas transfer process. The Center for Transportation and the Environment, a nonprofit focused on clean transport technologies, will provide independent technical assessment.
Fleet Scale and Funding
The station forms part of a broader infrastructure commitment by SamTrans, which serves more than 10 million riders annually across 74 fixed routes. In October 2024, the agency placed the largest single fuel cell bus order in New Flyer’s history — 108 Xcelsior CHARGE FC 40-foot buses valued at up to $168.25 million. The first ten entered service in early 2025, with deliveries continuing in phases through early 2027. SamTrans cites a daily range of approximately 300 miles for its hydrogen buses, against roughly 200 for battery-electric alternatives — a gap it considers material given the county’s topography and route lengths.
The infrastructure build-out is supported in part by $34.5 million from ARCHES (Alliance for Renewable Clean Hydrogen Energy Systems), California’s regional hydrogen hub and the first of seven federally designated hubs to sign its agreement with the US Department of Energy. The broader ARCHES programme involves up to $1.2 billion in federal funding and $11.4 billion in combined public and private investment.
Implications for Hydrogen Mobility
A construction timeline and hydrogen supply source for the new Fastech station have not yet been disclosed — an omission that will draw scrutiny given California’s recent supply difficulties. SamTrans has separately awarded Trillium a $17.4 million contract for a permanent station at its North Base Facility in South San Francisco, expected operational by summer 2027. The agency has set an internal target of eliminating diesel entirely by 2034, six years ahead of the California Air Resources Board’s 2040 zero-emission fleet mandate. If the CryoPump performs as claimed at commercial scale, it could meaningfully shift the economics of liquid hydrogen dispensing — a question the industry will watch closely as the SamTrans project moves from announcement to construction.
