Introduction Of Fuel Cell Vehicles Research Articles

Development of a Hydrogen Contaminant Detector

Hydrogen Refueling Stations (HRSs) are being deployed at scale in California, Japan, Europe and South Korea to support the introduction of Fuel Cell Vehicles.1 The hydrogen dispensed to the fuel cell should meet SAE J2719 standards for the maximum allowable concentration of various impurities.2 While HRSs can have their fuel analyzed periodically to verify that they meet the strict fuel quality standards, it would be greatly advantageous to have an in-linemonitor that can alert the user to any potential fuel quality problems. Los Alamos National Laboratory has been developing a low-cost hydrogen contaminant detector (HCD) that can be deployed at the HRS and is capable of detecting CO and H2S impurities in the hydrogen fuel.The LANL HCD technology is based on a hydrogen pumping cell that utilizes a high loaded counter/pseudo-reference electrode and a low loaded working/sensing electrode.3 This hydrogen pumping cell, illustrated in Figure 1, consists of a Nafion® 117 membrane that is in contact with a water reservoir and two gas diffusion electrodes with wicking tabs that extend into the water reservoir. The active electrode area (≈ 1cm2) is exposed to dry hydrogen gas that first flows over the sensing electrode and then over the pseudo-reference electrode. The HCD is operated in a constant potential mode (0.1V) where the pumping current can be related to the purity of hydrogen. A voltage pulse (1.5V for 30s) is applied periodically (e.g. every 15mins) to clean up any contaminants that are adsorbed on the working electrode and reset the HCD current to the baseline.The LANL HCD technology was installed at the H2Frontier HRS in Burbank, California and operated under real-world conditions. Calibration was performed on this HCD with certified CO/H2 gas, and its sensitivity to low concentrations of CO was demonstrated (Figure 2). The data shown in Figure 2 plots the current at 0.1V at the end of each 15-minute interval, just before the application of the 1.5V pulse. The HCD baseline and response were tracked intermittently for a period of over a year and demonstrated exceptional baseline stability and sensitivity to the SAE J2719 allowable limit of 100ppb CO. An analysis of the field-testing data will be presented along with the response to low concentrations (4 - 100 ppb) of H2S in H2.The current LANL HCD operates at slightly above ambient temperature (30 °C) and at ambient pressures. Any change in the flow rate of H2 (usually 100sccm) over the HCD, or a drying of the water reservoir can result in a baseline drift. LANL is currently working on a HCD technology that can function without a humidification system and thus is immune to flow rate changes. Moreover, this system could be operated under pressure and at varying temperatures and has the potential to be deployed in-line just before the fueling nozzle. The development of membranes with sufficient protonic conductivity to operate in dry hydrogen and their sensitivity to CO in the H2 will also be presented in this talk. Acknowledgements This research is supported by the U.S. Department of Energy Fuel Cell Technologies Office, through the Safety, Codes & Standards (SCS) sub-program (Project Manager: Laura Hill).REFERENCES: 1. Hardman, G. Tall, Int. J. Hydrogen Energy, 43, 17857-17866 (2018).2. San Marchi, E. S. Hecht, I. W. Ekoto, K. M. Groth, C. LaFleur, B. P. Somerday, R. Mukundan, T. Rockward, T; J. Keller, C. W. James, Int. J. Hydrogen Energy, 42(11), 7263-7274 (2017)3. Brosha, T. Rockward, C. J. Romero, M. S. Wilson, C. Kreller and R. Mukundan, U.S Patent # 10,490,833 (2019). Figure 1

How to finance for establishing hydrogen refueling stations in China? An analysis based on Fuzzy AHP and PROMETHEE

Fuel Cell Vehicles are considered as a promising alternative for future sustainable transportation, while the deployment of hydrogen refueling stations is one of the major barriers that blocking the commercial introduction of Fuel Cell Vehicles. Since the establishment of hydrogen infrastructures not only requires quite a large investment, but also needs efficient project management and operation. Therefore, how to finance and operate hydrogen infrastructures is a difficult question for decision makers. In this study, it introduced four business models for financing and operating hydrogen refueling stations: Build-Operate-Transfer, Transfer-Operate-Transfer, Public-Private-Partnership, and Asset- Backed Securitization, and identified six criteria for prioritizing them. Then, it employed Fuzzy Analytic Hierarchy Process to determine the weight for the criteria, and compared the performance of these models with respect each criterion. Finally, the method of Preference Ranking Organization Method for Enrichment Evaluations was used to determine the priority of each model for financing hydrogen refueling stations, and a Sensitivity Analysis was conducted to find the most appropriate model in different situations. The results indicated that financing difficulty, project risks, and financing costs are the most important factors for strategic investors to involve in financing hydrogen refueling stations. Among the four financing models, Public-Private-Partnership and Transfer-Operate-Transfer models are turned out to be more preferable for financing hydrogen infrastructure in China. Some policy implications have also been provided for the establishment of hydrogen refueling stations.

An analysis of future platinum resources, emissions and waste streams using a system dynamic model of its intentional and non-intentional flows and stocks

Platinum is increasingly used intentionally and non-intentionally in several applications. This has raised the concern about its future resources, emissions and losses during its life cycle. On the one hand, increasing platinum emissions might affect human health. On the other hand, the accumulated platinum in mineral waste, soil, landfill sites and construction materials as a result of the emissions, losses and the utilization of secondary materials can be seen as potential resources for platinum. This paper is aimed at (1) analyzing the long term impacts of the use of platinum intentionally and non-intentionally on its future demand and supply, release to the environment and accumulation in mineral waste, soil, landfill sites and construction materials and (2) quantifying the amount of platinum in secondary materials that would be available for platinum future supply. The analysis is carried out on a global level using a system dynamic model of platinum intentional and non-intentional flows and stocks. The analysis is based on four scenarios for the introduction of fuel cell vehicles (FCVs). The results show that platinum demand is increasing overtime in all scenarios at different rates and its identified resources are expected to deplete before the end of the century with or without the introduction of FCVs. The release of platinum to the environment and the accumulation in soil are expected to decrease when conventional ICE vehicles is replaced by FCVs. The amount of platinum accumulated in mineral waste, soil, landfill sites and construction materials by the time platinum is depleted are more than double its identified resources and would be potential resources for platinum that are available in different parts of the world. The methodology presented in this paper can be used in the assessment of other technologies and other metals.

Potential in New Zealand for use of hydrogen as a transportation fuel

New Zealand imports its vehicle fleet and essentially all transportation fuel. With introduction of fuel-cell vehicles, New Zealand can become self-sufficient in hydrogen fuel. A study undertaken by the Sustainable Energy Initiatives program at UNITEC evaluates the economic and environmental factors of fossil and non-fossil energy sources for production of hydrogen. It examines the transition for hydrogen fuel from on-board production from hydrocarbons to large-scale centralized electrolytic production. The paper extrapolates historic data on population, vehicle transport, and electric energy and examines the basis for introducing hydrogen fuel into the national economy in the 2010–2050 period.