Bus fleets: This evaluation includes ten 40-ft FCEBs built by New Flyer with an electric propulsion system and a Ballard fuel cell system.The baseline buses are ten 2016 model year New Flyer 40-ft CNG buses.Bus use: OCTA's average speed for its operation is around 13 mph.The agency reduced service in March 2020 due to the COVID-19 pandemic. Fuel economy and cost:The FCEBs had an average fuel economy of 8.39 miles per kilogram of hydrogen, which equates to 9.48 mpdge.The CNG buses had an average fuel economy of 3.77 mpgge, which equates to 4.22 mpdge.The FCEB fuel economy was approximately 2.3 times that of the CNG buses.Average hydrogen costs were $8.48/kg; CNG cost was $1.12/gge.The FCEBs had an average fuel cost of $1.01 per mile.The fuel cost for the CNG buses averaged $0.36 per mile.Fuel use: During the data period, OCTA fueled its FCEB fleet more than 2,530 times with an average fill amount of 20.17 kg.Daily dispensed hydrogen was 96 kg.mpdge = miles per diesel gallon equivalent mpgge = miles per gasoline gallon equivalent NREL | 5Results Summary (continued) Availability: The average availability for the FCEB fleet was 62.5%.Most unavailable time for the FCEBs was due to general bus-related problems followed by battery issues.This is not unusual for a new design in its first deployment.OCTA is working with the OEM to identify the issues.The availability for the fleet is expected to increase over time as these early issues are resolved.The average availability for the fuel cell system was 94.9%.OCTA reports that its CNG bus availability averages 80% or better. Maintenance cost:The cost to maintain the buses in the data period was $0.46/mi for the FCEBs and $0.66/mi for the CNG buses.Propulsion-system maintenance was $0.12 for the FCEBs compared to $0.29 for the CNG buses.Note that the FCEBs are under warranty and most repairs are covered by the OEM.Much of the cost is labor to troubleshoot issues. NREL | 6 Fleet ProfileThe Orange County Transportation Authority-OCTA -is Orange County California's transportation agency, responsible for

This report–prepared by NREL and UC Berkeley for the California Air Resources Board (CARB)–provides a comprehensive review conducted for implementation of the Innovative Clean Transit (ICT) regulation and deployment of zero-emission transit buses in California. The ICT regulation requires California transit agencies to begin transitioning to zero-emission vehicle technologies, defining an increasing percentage of new bus purchases that must be zero-emission buses (ZEBs) each year. The purchase requirements begin in 2023, increasing to a 100% ZEB purchase requirement beginning in 2029. This schedule is designed to result in 100% ZEB fleets statewide by 2040. The focus of the Phase I study was on implementation progress, status of standard-size transit buses, and the California transit industry's readiness to meet the 2023 ICT purchase requirements.

This document includes results and experiences

This report presents early results from a deployment of fuel cell electric buses (FCEBs) operated by SunLine Transit Agency in the Coachella Valley area of California. The five FCEBs, produced by New Flyer, feature an electric drive propulsion system powered by a Ballard fuel cell system. The project team is collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. The goal of this evaluation is to compare the FCEB performance to that of conventional technology and to track progress over time toward meeting the technical targets set by DOE and the Department of Transportation (DOT). The FCEBs were delivered beginning in mid-2019. The data period covers January 2020 through July 2020. NREL collects data on five 2019 model year compressed natural gas (CNG) buses as a baseline comparison at SunLine. These new CNG buses were phased into service beginning in April 2020.

This report presents early results from a deployment of fuel cell electric buses (FCEBs) operated by Orange County Transportation Authority (OCTA) in Southern California. The ten FCEBs, produced by New Flyer, feature an electric drive propulsion system powered by a Ballard fuel cell system. The project team is collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. The goal of this evaluation is to compare the FCEB performance to that of conventional technology and to track progress over time toward meeting the technical targets set by DOE and the Department of Transportation (DOT). The FCEBs were delivered beginning in late-2019, and were placed in service on February 9, 2020. The data period covers February 2020 through July 2020. NREL collects data on ten 2016 model year compressed natural gas (CNG) buses as a baseline comparison at OCTA.

This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of results from evaluations performed by the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory. This annual status report combines results from all FCEB demonstrations, tracks the progress of the FCEB industry toward meeting technical targets, documents the lessons learned, and discusses the path forward for commercial viability of fuel cell technology for transit buses. The data from these early FCEB deployments funded by the U.S. Department of Transportation, state agencies, and the private sector help to guide future early-stage research and development supported by DOE's Fuel Cell Technologies Office. The 2018 summary results primarily focus on the most recent year for each demonstration, from August 2017 through July 2018. NREL has included an up-to-date analysis of operational costs including scheduled and unscheduled cost and cost per mile by system. The primary results presented in the report are from five demonstrations of two different fuel-cell-dominant bus designs.

Pressure relief devices (PRDs ) are used to protect high pressure systems from burst failure caused by overpressurization. Codes and standards require the use of PRDs for the safe design of many pressurized systems. These systems require high reliability due to the risks associated with a burst failure. Hydrogen service can increase the risk of PRD failure due to material property degradation caused by hydrogen attack. The National Renewable Energy Laboratory (NREL) has conducted an accelerated life test on a conventional spring loaded PRD. Based on previous failures in the field, the nozzles specific to these PRDs are of particular interest. A nozzle in a PRD is a small part that directs the flow of fluid toward the sealing surface to maintain the open state of the valve once the spring force is overcome. The nozzle in this specific PRD is subjected to the full tensile force of the fluid pressure. These nozzles are made from 440C material, which is a type of hardened steel that is commonly chosen for high pressure applications because of its high strength properties. In a hydrogen environment, however, 440C is considered a worst case material since hydrogen attack results in a loss of almost all ductility and thus 440C is prone to fatigue and material failure. Accordingly, 440C is not recommended for hydrogen service. Conducting an accelerated life test on a PRD with 440C material provides information on necessary and sufficient conditions required to produce crack initiation and failure. The accelerated life test also provides information on other PRD failure modes that are somewhat statistically random in nature.

The United Nations Economic Commission for Europe Global Technical Regulation (GTR) Number 13 (Global Technical Regulation on Hydrogen and Fuel Cell Vehicles) is the defining document regulating safety requirements in hydrogen vehicles, and in particular, fuel cell electric vehicles (FCEVs). GTR Number 13 has been formally adopted and will serve as the basis for the national regulatory standards for FCEV safety in North America (led by the United States), Japan, Korea, and the European Union. The GTR defines safety requirements for these vehicles, including specifications on the allowable hydrogen levels in vehicle enclosures during in-use and post-crash conditions and on the allowable hydrogen emissions levels in vehicle exhaust during certain modes of normal operation. However, in order to be incorporated into national regulations, that is, to be legally binding, methods to verify compliance with the specific requirements must exist. In a collaborative program, the Sensor Laboratories at the National Renewable Energy Laboratory in the United States and the Joint Research Centre, Institute for Energy and Transport in the Netherlands have been evaluating and developing analytical methods that can be used to verify compliance with the hydrogen release requirements as specified in the GTR.

This report, published annually, summarizes the progress of fuel cell electric bus development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. Funding for this effort is provided by the U.S. Department of Energy's Fuel Cell Technologies Office within the Office of Energy Efficiency and Renewable Energy and by the U.S. Department of Transportation's Federal Transit Administration. The 2016 summary results primarily focus on the most recent year for each demonstration, from August 2015 through July 2016. The results for these buses account for more than 550,000 miles traveled and 59,500 hours of fuel cell power system operation. The primary results presented in the report are from three demonstrations of two different fuel-cell-dominant bus designs: Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California; American Fuel Cell Bus Project at SunLine Transit Agency in California; and American Fuel Cell Bus Project at the University of California at Irvine.

NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Acknowledgments This evaluation at Foothill Transit would not have been possible without the support and cooperation of many people. The authors thank the following individuals: Ah amp-hours BEB battery electric bus CARB California Air Resources Board CNG compressed natural gas DGE diesel gallon equivalent DOE U.S. Department of Energy ESS energy storage system FCEB fuel cell electric bus ft feet FTA Federal Transit Administration GGE gasoline gallon equivalent GVWR gross vehicle weight rating hp horsepower HVAC heating, ventilation, and air conditioning in. inches kg kilograms kW kilowatts kWh kilowatt hours lb pounds MBRC miles between roadcalls mph miles per hour NREL National Renewable Energy Laboratory PMI preventive maintenance inspection psi pounds per square inch PTC Pomona Transit Center SI International System of Units SOC state of charge TIGGER Transit Investments for Greenhouse Gas and Energy Reduction TRL technology readiness level ZBus zero emission bus v This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. Availability: The number of days the buses are actually available compared to the days that the buses are planned for operation expressed as percent availability. Clean point: For each evaluation, NREL works with the project partners to determine a starting point—or clean point—for the data analysis period. The clean point is chosen to avoid some of the early and expected operations problems with a new vehicle going into service, such as early maintenance campaigns. In some cases, reaching the clean point may require 3 to 6 months of operation before the evaluation can start. Deadhead: The miles and hours that a vehicle travels when out of revenue …