Moving Beyond the Colors: The Full Life-Cycle Emissions of Hydrogen Production Pathways for California

There is growing interest in the use of hydrogen as a transportation fuel but the environmental benefits of using hydrogen depend critically on how it is produced and distributed. Leading alternatives to using fossil natural gas to make hydrogen through the conventional method of steam methane reforming include using electrolyzers to split water into hydrogen and oxygen, and the use of biogas as an alternative feedstock to fossil natural gas. This report examines the latest carbon intensity (CI) estimates for these and various other hydrogen production processes, adding important nuances to the general “colors of hydrogen” scheme that has been used in recent years. CI values for hydrogen production can vary widely both within and across hydrogen production pathways. The lowest CI pathways use biomass or biogas as a feedstock, and solar or wind power. The report also analyses jobs creation from new hydrogen production facilities and shows that these benefits can be significant for large-scale facilities based on either future biomass/biogas-to-hydrogen or solar-hydrogen production technologies. Recommendations include setting stricter goals for the state’s Low Carbon Fuel Standard (LCFS) program to continue to reduce the carbon footprint of California’s transportation fuels

Exploring the Costs of Electrification for California’s Transit Agencies

The California Air Resources Board is considering regulatory changes to require an increasing share of public transit buses to produce zero-emissions by 2040. This report attempts to identify and assess critical drivers of electric bus adoption costs, characterize uncertainty in forecasting agency transition costs, and provide an approach to support agencies’ assessment of strategic investments in new vehicle technologies. While current purchase costs for electric buses are 40% higher compared to conventional diesel or clean-natural gas buses, by 2030, electric buses are likely to become the most cost-effective option. Taking total cost of ownership into consideration, replacing a bus fleet by 2030 with a 100% electric fleet is estimated to decrease overall costs by $0.1 to$3.6B compared to replacing the current fleet. Results are likely to vary depending on agency size as small and rural agencies have orders of magnitude smaller fleets than the largest agencies and the estimates take into account current subsides for purchases electric buses. The report concludes that total costs of ownership for electric buses are likely to be lower than current fleets and that agencies need better tools to be able to evaluate integrated technology and systems planning, particularly as it relates to transit bus electrification

Exploring the Costs of Electrification for California’s Transit Agencies

The California Air Resources Board is considering regulatory changes to require an increasing share of public transit buses to produce zero-emissions by 2040. This report attempts to identify and assess critical drivers of electric bus adoption costs, characterize uncertainty in forecasting agency transition costs, and provide an approach to support agencies’ assessment of strategic investments in new vehicle technologies. While current purchase costs for electric buses are 40% higher compared to conventional diesel or clean-natural gas buses, by 2030, electric buses are likely to become the most cost-effective option. Taking total cost of ownership into consideration, replacing a bus fleet by 2030 with a 100% electric fleet is estimated to decrease overall costs by $0.1 to$3.6B compared to replacing the current fleet. Results are likely to vary depending on agency size as small and rural agencies have orders of magnitude smaller fleets than the largest agencies and the estimates take into account current subsides for purchases electric buses. The report concludes that total costs of ownership for electric buses are likely to be lower than current fleets and that agencies need better tools to be able to evaluate integrated technology and systems planning, particularly as it relates to transit bus electrification

Effects of Increased Weights of Alternative Fuel Trucks on Pavement and Bridges

California’s truck fleet composition is shifting to include more natural gas vehicles (NGVs), electric vehicles (EVs), and fuel cell vehicles (FCVs), and it will shift more quickly to meet state greenhouse gas (GHG) emission goals. These alternative fuel trucks (AFTs) may introduce heavier axle loads, which may increase pavement damage and GHG emissions from work to maintain pavements. This project aimed to provide conceptual-level estimates of the effects of vehicle fleet changes on road and bridge infrastructure. Three AFT implementation scenarios were analyzed using typical Calif. state and local pavement structures, and a federal study’s results were used to assess the effects on bridges. This study found that more NGV, EV, and FC trucks are expected among short-haul and medium-duty vehicles than among long-haul vehicles, for which range issues arise with EVs and FCs. But the estimates predicted that by 2050, alternative fuels would power 25–70% of long-haul and 40–95% of short-haul and medium-duty trucks. AFT implementation is expected to be focused in the 11 counties with the greatest freight traffic—primarily urban counties along major freight corridors. Results from the implementation scenarios suggest that introducing heavier AFTs will only result in minimal additional pavement damage, with its extent dependent on the pavement structure and AFT implementation scenario. Although allowing weight increases of up to 2,000 lbs. is unlikely to cause major issues on more modern bridges, the effects of truck concentrations at those new limits on inadequate bridges needs more careful evaluation. The study’s most aggressive market penetration scenario yielded an approximate net reduction in annual well-to-wheel truck propulsion emissions of 1,200–2,700 kT per year of CO2 -e by 2030, and 6,300–34,000 kT by 2050 versus current truck technologies. Negligible effects on GHG emissions from pavement maintenance and rehabilitation resulted from AFT implementation

Effects of Increased Weights of Alternative Fuel Trucks on Pavement and Bridges

California’s truck fleet composition is shifting to include more natural gas vehicles (NGVs), electric vehicles (EVs), and fuel cell vehicles (FCVs), and it will shift more quickly to meet state greenhouse gas (GHG) emission goals. These alternative fuel trucks (AFTs) may introduce heavier axle loads, which may increase pavement damage and GHG emissions from work to maintain pavements. This project aimed to provide conceptual-level estimates of the effects of vehicle fleet changes on road and bridge infrastructure. Three AFT implementation scenarios were analyzed using typical Calif. state and local pavement structures, and a federal study’s results were used to assess the effects on bridges. This study found that more NGV, EV, and FC trucks are expected among short-haul and medium-duty vehicles than among long-haul vehicles, for which range issues arise with EVs and FCs. But the estimates predicted that by 2050, alternative fuels would power 25–70% of long-haul and 40–95% of short-haul and medium-duty trucks. AFT implementation is expected to be focused in the 11 counties with the greatest freight traffic—primarily urban counties along major freight corridors. Results from the implementation scenarios suggest that introducing heavier AFTs will only result in minimal additional pavement damage, with its extent dependent on the pavement structure and AFT implementation scenario. Although allowing weight increases of up to 2,000 lbs. is unlikely to cause major issues on more modern bridges, the effects of truck concentrations at those new limits on inadequate bridges needs more careful evaluation. The study’s most aggressive market penetration scenario yielded an approximate net reduction in annual well-to-wheel truck propulsion emissions of 1,200–2,700 kT per year of CO2 -e by 2030, and 6,300–34,000 kT by 2050 versus current truck technologies. Negligible effects on GHG emissions from pavement maintenance and rehabilitation resulted from AFT implementation