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Open Access Publications from the University of California


Sustainable Transportation Energy Pathways (STEPS) is a four-year (2015-2018) multidisciplinary research consortium, part of the Institute of Transportation Studies at the University of California, Davis.

Sustainable Transportation Energy Pathways (STEPS)

There are 3 publications in this collection, published between 2015 and 2017.
Research Reports (3)

The Potential to Build Current Natural Gas Infrastructure to Accommodate the Future Conversion to Near-Zero Transportation Technology

The emergence of natural gas as an abundant, inexpensive fuel in the United States has highlighted the possibility that natural gas could play a significant role in the transition to low carbon fuels. Natural gas is often cited as a “bridge” to low carbon fuels in the transportation sector. Major corporations are already investing billions of dollars to build infrastructure to feed natural gas into the U.S. trucking industry and expand the use of natural gas in fleets. In the state of California, natural gas fueling infrastructure is expanding, especially in and around the ports of Los Angeles and Long Beach. The use of natural gas fueled medium and heavy duty fleets is currently on an upswing. The authors examine the precise natural gas infrastructure that is economically and technologically synergistic for both natural gas and renewable natural gas in the near-term, and alternative fuels like renewable natural gas (RNG) and hydrogen in the long term. In particular, the authors examine optimum paths for developing infrastructure in the near-term that will accommodate alternative fuels once they become available at the commercial scale. The original design of the Low Carbon Fuel Standard (LCFS) provides time for the development of advanced, near zero technologies. The authors consider the credits from the LCFS in our analysis.

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Strategies for Transitioning to Low-Carbon Emission Trucks in the United States

This white paper reviews previous studies on prospects for reducing CO2 emissions from trucks. It provides a new investigation into the feasibility of achieving an 80% reduction in CO2-equivalent (CO2e) greenhouse gas (GHG) emissions in the United States and California from trucks by 2050. The authors assess the technological and economic potential of achieving deep market penetrations of low-carbon vehicles and fuels, including vehicles operating on electricity, hydrogen, and biofuels. Achieving such a target for trucks will be very challenging and, if focused on hydrogen and electric zero emission vehicle (ZEV) technologies, will require strong sales growth beginning no later than 2025.

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Assessment of Critical Barriers to Alternative and Renewable Fuel and Vehicle Deployment – Workshop Series

The University of California, Davis and the California Energy Commission held a series of three Emerging Technologies Workshops in late 2015 and early 2016. The goal of these workshops was to identify environmentally and economically promising alternative fuel and vehicle emerging technologies, and to identify and evaluate the critical business and policy barriers blocking their widespread adoption in the State and develop solutions for those barriers. Additionally, the workshops were to analyze the broad range of commercial barriers and identify strategies to increase the adoption and rapid scale-up of emerging technologies, fuels and fueling infrastructure that will help the state achieve its goals for air quality and greenhouse gas emissions. Each of these workshops convened groups of over 100 stakeholders engaged in the commercialization of emerging technologies for the light-, medium- and heavy-duty transportation sectors. Participants included manufacturers of incumbent and emerging alternative vehicle technologies, manufacturers of traditional and alternative fueling infrastructure, traditional and alternative fuel (including electricity) producers and supplies, financial institutions and investors, and public agencies concerned with energy, the environment, transportation, and the California economy.

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