DOT HS 811 267 February 2010 Analysis of Published Hydrogen Vehicle Safety Research DISCLAIMER This publication is distributed by the U.S. Department of Transportation, National Highway Traffic Safety Administration, in the interest of information exchange. The opinions, findings, and conclusions expressed in this publication are those of the authors and not necessarily those of the Department of Transportation or the National Highway Traffic Safety Administration. The United States Government assumes no liability for its contents or use thereof. If trade names, manufacturers’ names, or specific products are mentioned, it is because they are considered essential to the object of the publication and should not be construed as an endorsement. The United States Government does not endorse products or manufacturers. TECHNICAL REPORT DOCUMENTATION PAGE 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. DOT HS 811 267 4. Title and Subtitle 5. Report Date Analysis of Published Hydrogen Vehicle Safety Research February 2010 6. Performing Organization Code NHTSA/NVS-312 7. Author(s) 8. Performing Organization Report Stephanie Flamberg, Susan Rose, Denny Stephens – Battelle Memorial Institute No. 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Battelle Memorial Institute 11. Contract or Grant No. 505 King Avenue DTNH22-08-D-00080 Columbus, Ohio 43201 12. Sponsoring Agency Name and Address 13. Type of Report and Period National Highway Traffic Safety Administration Covered 1200 New Jersey Avenue SE. Final Washington, DC 20590 14. Sponsoring Agency Code 15. Supplementary Notes 16. Abstract Hydrogen-fueled vehicles (HFVs) offer the promise of providing safe, clean, and efficient transportation in a setting of rising fuel prices and tightening environmental regulations. However, the technologies needed to store or manufacture hydrogen onboard and deliver it to the propulsion system differs from conventionally-fueled vehicles. These differences present challenges to engineers and scientists in the development of HFVs that are safe and practical for every day use. For many years, researchers have been meeting these challenges through the development of new designs, testing and analyses to ensure hydrogen-fueled vehicles are no more hazardous to own and operate than conventionally-fueled vehicles and meet the same or similar performance requirements. The National Highway Traffic Safety Administration (NHTSA) recognizes the value in understanding the hydrogen and fuel cell research being conducted by other national and international organizations and has requested that Battelle undertake a review of recently published hydrogen vehicle and safety research. The intent of this program is to identify technical documents directly related to the safety performance of HFVs and to organize the content of this research in a format that is logical and searchable. Ultimately, the information provided in this project is intended to help NHTSA guide future program planning by avoiding redundancy and overlap in similar research areas and highlighting opportunities for complementary or cooperative research in other areas. Future generations of hydrogen vehicles will continue to focus on safety and the need to achieve viable cruising ranges through lower cost and higher efficiency hydrogen storage. This focus is evident in the major research themes identified during Battelle’s review of nearly 100 HFV technical papers and presentations. The major themes in HFV safety research involve: • Hydrogen leak, dispersion, and ignition research (modeling and testing) • Enhancing existing hydrogen vehicle and container fire (bonfire) test methodologies (modeling and/or testing to improve specifications) • Compressed hydrogen container ruptures in the event of pressure relief device (PRD) failure (testing to determine consequences) • General hydrogen vehicle safety research (fuel cell safety, safety and risk analysis, vehicle demonstration programs, and codes and standards) • Hydrogen cylinder design and testing • Fast-fueling of 70 MPa compressed hydrogen containers (modeling and testing of thermal loads) • Liquefied Hydrogen (LH2) storage system components and vehicles (design, testing, and demonstration) • Incident data for compressed natural gas (CNG) containers 17. Key Words 18. Distribution Statement Hydrogen fueled vehicle, hydrogen leak, fuel cell vehicle Document is available to the public from the National Technical Information Service www.ntis.dot.gov 19. Security Classif. (of this 20. Security Classif. (of this 21. No. of Pages 22. Price report) page) 322 Unclassified Unclassified Form DOT F 1700.7 (8-72) Reproduction of completed page authorized i FINAL REPORT Approved Organization/Name Notes Date: Battelle RECORD OF REVISIONS Sections Version Description of Changes Date Approval Affected 0.1 ALL Initial Draft 5/8/09 D. Stephens ii Table of Contents Page Executive Summary ....................................................................................................................... iv Acronyms And Abbreviations ...................................................................................................... xii 1.0 Introduction ................................................................................................................ 1 1.1. Project Objectives ...................................................................................................... 1 1.2. Technical Approach ................................................................................................... 2 2.0 Identify Source Material ............................................................................................ 4 3.0 Review Content And Categorize Results ................................................................. 24 4.0 Assess Relevancy To Current Vehicle Designs ....................................................... 36 5.0 Summary Of HFV Safety Research ......................................................................... 50 5.1. Hydrogen Leak, Dispersion, and Ignition Research ................................................ 50 5.2. Enhancing Existing Hydrogen Vehicle and Container Fire (Bonfire) Test Methodologies.......................................................................................................... 61 5.3. Compressed Hydrogen Container Rupture Research (PRD failure) ........................ 66 5.4. General Hydrogen Vehicle Safety Research ............................................................ 67 5.5. Hydrogen Cylinder Design and Testing .................................................................. 72 5.6. Fast-Fueling of 70 MPa Compressed Hydrogen Storage Containers ...................... 78 5.7. Liquefied Hydrogen (LH2) Storage System Components and Vehicles ................. 81 5.8. Incident Data for Compressed Natural Gas (CNG) Containers ............................... 85 6.0 References ................................................................................................................ 87 Appendix A - Summaries Of Research Documents ................................................................... A-1 List of Tables Table 1. Bibliography of Source Material ..................................................................................... 6 Table 2. Organization and Categorization of Source Material Format ........................................ 26 Table 3. Current Hydrogen Vehicle Designs and Manufacturers ................................................ 40 List of Figures Figure 1. Vehicle, System, and Component Categories for Research Review ............................ 24 iii EXECUTIVE SUMMARY Hydrogen-fueled vehicles (HFVs) offer the promise of providing safe, clean, and efficient transportation in a setting of rising fuel prices and tightening environmental regulations. However, the technologies needed to store or manufacture hydrogen onboard and deliver it to the propulsion system differs from conventionally-fueled vehicles. These differences present challenges to engineers and scientists in the development of HFVs that are safe and practical for every day use. For many years, researchers have been meeting these challenges through the development of new designs, testing and analyses to ensure hydrogen-fueled vehicles are no more hazardous to own and operate than conventionally-fueled vehicles and meet the same or similar performance requirements. The National Highway Traffic Safety Administration (NHTSA) recognizes the value in understanding the hydrogen and fuel cell research being conducted by other national and international organizations and has requested that Battelle undertake a review of recently published hydrogen vehicle and safety research. The intent of this program is to identify technical documents directly related to the safety performance of HFVs and to organize the content of this research in a format that is logical and searchable. Ultimately, the information provided in this project is intended to help NHTSA guide future program planning by avoiding redundancy and overlap in similar research areas and highlighting opportunities for complementary or cooperative research in other areas. Future generations of hydrogen vehicles will continue to focus on safety and the need to achieve viable cruising ranges through lower cost and higher efficiency hydrogen storage. This focus is evident in the major research themes identified during Battelle’s review of nearly 100 HFV technical papers and presentations. The major themes