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Natural ventilation is a well-known passive mitigation method to limit hydrogen build-up in confined spaces in case of accidental release [1-3]. In most cases a basic design of H2 infrastructure is adopted and vents installed for natural ventilation are adjusted according to safety targets and constraints of the considered structure. With the growing H2 mobility market the demand for H2 refueling infrastructure in our urban environment is on the rise. In order to meet both safety requirements and societal acceptance the design of such infrastructure is becoming more important. In this study a novel design concept is proposed for the hydrogen refueling station (HRS) by modifying physical structure while keeping safety consideration as the top priority of the concept. In this collaborative project between Air Liquide and the University of Delaware an extensive evaluation was performed on new structures of the processing container and dispenser of HRS by integrating safety protocols via passive means. Through a SWOT analysis combined with the most relevant approaches including analytical engineering models numerical simulations [4] and dedicated experimental trials an optimized design was obtained and its safety enhancement was fully evaluated. A small-scale processing container and an almost full-scale dispenser were built and tested to validate the design concepts by simulating accidental H2 release scenarios and assessing the associated consequences in terms of accumulation and potential flammable volumes formation. A conical dispenser and a V-shaped roof-top processing container which were easy to build and implement were designed and tested for this proof-of-concept study. This unique methodology from conception fundamental analysis investigation and validation through experimental design execution and evaluation is fully described in this study.

This perspective article delves into the critical role of hydrogen as a sustainable energy carrier in the context of the ongoing global energy transition. Hydrogen with its potential to decarbonize various sectors has emerged as a key player in achieving decarbonization and energy sustainability goals. This article provides an overview of the current state of hydrogen technology its production methods and its applications across diverse industries. By exploring the challenges and opportunities associated with hydrogen integration we aim to shed light on the pathways toward achieving a sustainable hydrogen economy. Additionally the article underscores the need for collaborative efforts among policymakers industries and researchers to overcome existing hurdles and unlock the full potential of hydrogen in the transition to a low-carbon future. Through a balanced analysis of the present landscape and future prospects this perspective article aims to contribute valuable insights to the discourse surrounding hydrogen’s role in the global energy transition.

The present paper offers a thorough examination of the safety measures enforced at hydrogen filling stations emphasizing their crucial significance in the wider endeavor to advocate for hydrogen as a sustainable and reliable substitute for conventional fuels. The analysis reveals a wide range of crucial safety aspects in hydrogen refueling stations including regulated hydrogen dispensing leak detection accurate hydrogen flow measurement emergency shutdown systems fire-suppression mechanisms hydrogen distribution and pressure management and appropriate hydrogen storage and cooling for secure refueling operations. The paper therefore explores several aspects including the sophisticated architecture of hydrogen dispensers reliable leak-detection systems emergency shut-off mechanisms and the implementation of fire-suppression tactics. Furthermore it emphasizes that the safety and effectiveness of hydrogen filling stations are closely connected to the accuracy in the creation and upkeep of hydrogen dispensers. It highlights the need for materials and systems that can endure severe circumstances of elevated pressure and temperature while maintaining safety. The use of sophisticated leak-detection technology is crucial for rapidly detecting and reducing possible threats therefore improving the overall safety of these facilities. Moreover the research elucidates the complexities of emergency shut-off systems and fire-suppression tactics. These components are crucial not just for promptly managing hazards but also for maintaining the station’s structural soundness in unanticipated circumstances. In addition the study provides observations about recent technical progress in the industry. These advances effectively tackle current safety obstacles and provide the foundation for future breakthroughs in hydrogen fueling infrastructure. The integration of cutting-edge technology and materials together with the development of upgraded safety measures suggests a positive trajectory towards improved efficiency dependability and safety in hydrogen refueling stations.

Hydrogen primarily produced from steam methane reforming plays a crucial role in oil refining and provides a solution for the oil and gas industry's long-term energy transition by reducing CO2 emissions. This paper examines hydrogen’s role in this transition. Firstly experiences from oil and gas exploration including in-situ gasification can be leveraged for hydrogen production from subsurface natural hydrogen reservoirs. The produced hydrogen can serve as fuel for generating steam and heat for thermal oil recovery. Secondly hydrogen can be blended into gas for pipeline transportation and used as an alternative fuel for oil and gas hauling trucks. Additionally hydrogen can be stored underground in depleted gas fields. Lastly oilfield water can be utilized for hydrogen production using geothermal energy from subsurface oil and gas fields. Scaling up hydrogen production faces challenges such as shared use of oil and gas infrastructures increased carbon tax for promoting blue hydrogen and the introduction of financial incentives for hydrogen production and consumption hydrogen leakage prevention and detection.

Hydrogen fuel cell vehicles (HFCVs) are a promising technology for reducing vehicle emissions and improving energy efficiency. Due to the ongoing evolution of this technology there is limited comprehensive research and documentation regarding the energy modeling of HFCVs. To address this gap the paper develops a simple HFCV energy consumption model using new fuel cell efficiency estimation methods. Our HFCV energy model leverages real-time vehicle speed acceleration and roadway grade data to determine instantaneous power exertion for the computation of hydrogen fuel consumption battery energy usage and overall energy consumption. The results suggest that the model’s forecasts align well with real-world data demonstrating average error rates of 0.0% and −0.1% for fuel cell energy and total energy consumption across all four cycles. However it is observed that the error rate for the UDDS drive cycle can be as high as 13.1%. Moreover the study confirms the reliability of the proposed model through validation with independent data. The findings indicate that the model precisely predicts energy consumption with an error rate of 6.7% for fuel cell estimation and 0.2% for total energy estimation compared to empirical data. Furthermore the model is compared to FASTSim which was developed by the National Renewable Energy Laboratory (NREL) and the difference between the two models is found to be around 2.5%. Additionally instantaneous battery state of charge (SOC) predictions from the model closely match observed instantaneous SOC measurements highlighting the model’s effectiveness in estimating real-time changes in the battery SOC. The study investigates the energy impact of various intersection controls to assess the applicability of the proposed energy model. The proposed HFCV energy model offers a practical versatile alternative leveraging simplicity without compromising accuracy. Its simplified structure reduces computational requirements making it ideal for real-time applications smartphone apps in-vehicle systems and transportation simulation tools while maintaining accuracy and addressing limitations of more complex models.

This week’s episode is a discussion between EAH hosts Patrick Molloy Alicia Eastman and Chris Jackson. The team cover the current status of hydrogen regulation innovation financing markets and consolidation. Hanging over most conversations in the decarbonization or future fuels space is the perpetual question: When will investors actually step up with significant capital to help companies make it through the development desert instead of letting promising companies languish in the double dunes of despair? There has been a lot of talk but not a lot of action. Listen to the team unpack recent developments and hopes for the future.

The podcast can be found on their website.

The production of hydrogen-based dense energy carriers (DECs) has been proposed as a combined solution for the storage and dispatch of power generated through intermittent renewables. Frameworks that model and optimize the production storage and dispatch of generated energy are important for data-driven decision making in the energy systems space. The proposed multiperiod framework considers the evolution of technology costs under different levels of promotion through research and targeted policies using the year 2021 as a baseline. Furthermore carbon credits are included as proposed by the 45Q tax amendment for the capture sequestration and utilization of carbon. The implementation of the mixed-integer linear programming (MILP) framework is illustrated through computational case studies to meet set hydrogen demands. The trade-offs between different technology pathways and contributions to system expenditure are elucidated and promising configurations and technology niches are identified. It is found that while carbon credits can subsidize carbon capture utilization and sequestration (CCUS) pathways substantial reductions in the cost of novel processes are needed to compete with extant technology pathways. Further research and policy push can reduce the levelized cost of hydrogen (LCOH) by upwards of 2 USD/kg.

The transportation industry’s transition to carbon neutrality is essential for addressing sustainability concerns. This study details a model for calculating the carbon footprint of the transportation sector as it progresses towards carbon neutrality. The model aims to support policymakers in estimating the potential impact of various decisions regarding transportation technology and infrastructure. It accounts for energy demand technological advancements and infrastructure upgrades as they relate to each transportation market: passenger vehicles commercial vehicles aircraft watercraft and trains. A technology roadmap underlies this model outlining anticipated advancements in batteries hydrogen storage biofuels renewable grid electricity and carbon capture and sequestration. By estimating the demand and the technologies that comprise each transportation market the model estimates carbon emissions. Results indicate that based on the technology roadmap carbon neutrality can be achieved by 2070 for the transportation sector. Furthermore the model found that carbon neutrality can still be achieved with slippage in the technology development schedule; however delays in infrastructure updates will delay carbon neutrality while resulting in a substantial increase in the cumulative carbon footprint of the transportation sector.

Financing sizing operating or upgrading a hydrogen refueling station (HRS) is challenging and may be complex much more so in today's rapidly changing and growing hydrogen industry. There is a significant information gap regarding experimental hydrogen station activities. A high-level perspective on such data and information may facilitate the transition between present and future HRS operations. To address the need for such high-level perspective this paper presents a comprehensive data set on the performance of the California State University Los Angeles Hydrogen Research and Fueling Facility based on multi-year operational data. The analysis of over 4500 refueling events and over 8800 kg of hydrogen dispensed as well as the operation of the facility electrolyzer and of both storage and refueling compressors from 2016 to 2020 reveals a comprehensive picture of HRS energy performance and the identification of useful key performance indicators. In 2016 the station's energy efficiency was 25% but in 2017 and the first three quarters of 2018 it dropped to 15%. Station-specific energy consumption increased during these quarters. The 2020 first quarter energy consumption was between 70 and 80 kWh/kg. At this time the energy efficiency of the station reached 40%.<br/>This research is based on an unprecedented and unique dataset of an HRS operating under real-world conditions with an approach that can be informative for modeling the performance of other stations providing a dataset that HRS designers operators and investors may utilize to make data-driven choices regarding HRS components and their specs and size as well as operating strategies.

Civil aviation provides an essential transportation network that connects the world and supports global economic growth. To maintain these benefits while meeting environmental goals next-generation aircraft must have drastically reduced climate impacts. Hydrogen-powered aircraft have the potential to fly existing routes with no carbon emissions and reduce or eliminate other emissions. This paper is a comprehensive guide to hydrogen-powered aircraft that explains the fundamental physics and reviews current technologies. We discuss the impact of these technologies on aircraft design cost certification and environment. In the long term hydrogen aircraft appear to be the most compelling alternative to today’s kerosene-powered aircraft. Using hydrogen also enables novel technologies such as fuel cells and superconducting electronics which could lead to aircraft concepts that are not feasible with kerosene. Hydrogen-powered aircraft are technologically feasible but require significant research and development. Lightweight liquid hydrogen tanks and their integration with the airframe is one of the critical technologies. Fuel cells can eliminate in-flight emissions but must become lighter more powerful and more durable to make large fuel cell-powered transport aircraft feasible. Hydrogen turbofans already have these desirable characteristics but produce some emissions albeit much less damaging than kerosene turbofans. Beyond airframe and propulsion technologies the viability of hydrogen aircraft hinges on low-cost green hydrogen production which requires massive investments in the energy infrastructure.