State of Sustainable Fleets Market Brief shows momentum in 2024

In California, the 2025 State of Sustainable Fleets Market Brief provides a comprehensive analysis of an industry confronting unprecedented regulatory uncertainty while demonstrating growth and resilience through continued investment in sustainable transportation solutions. Authored by TRC Companies, a global professional services firm providing integrated strategy, consulting, engineering and applied technologies in support of the energy transition, the findings were unveiled at the Advanced Clean Transportation (ACT) Expo in Anaheim, California, the premier annual conference for commercial transportation professionals. 

The past year has marked a period of significant transformation, characterized by rapid federal policy shifts and persistent state-led efforts to advance zero-emission vehicle (ZEV) and near-zero-emission (NZE) technologies, such as electric and natural gas vehicles, respectively. Recent regulatory changes and federal funding adjustments, coupled with substantial economic uncertainty, have introduced a period of peak complexity for fleet operators.  

Despite this, more than $13.5 billion in state and local funding remains available for ZE and NZE projects, driving continued adoption of renewable fuels, compressed natural gas vehicles (CNG), battery-electric vehicles (BEVs), and hydrogen fuel cell electric vehicles (FCEVs). 

In 2024, renewable diesel (RD) production increased by 28% in the first half of the year compared to the same period in 2023, with fleets reporting a record-high 39% adoption rate in the history of the annual fleet survey. Renewable natural gas (RNG) supply has surged by 234% over the past six years, supported by a 63% increase in natural gas stations offering RNG and vehicle sales hold steady. Meanwhile, BEV deliveries reached a record 41,472 medium- and heavy-duty (MD/HD) units, driven largely by commercial cargo vans and pickup trucks, which accounted for 92% of new registrations, despite pauses and adjusted forecasts by several manufacturers last year. Hydrogen fuel cell deployments also gained momentum despite two high-profile manufacturer bankruptcies, with 75 new transit buses and 165 MD/HD vehicles delivered in 2024.