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The Trajectory of Hybrid and Hydrogen Technologies in North American Heavy Haul Operations
Jul 2021
Publication
The central aim of this paper is to provide an up-to-date snapshot of hybrid and hydrogen technology-related developments and activities in the North American heavy haul railway setting placed in the context of the transportation industry more broadly. An overview of relevant alternative propulsion technologies is provided including a discussion of applicability to the transportation sector in general and heavy haul freight rail specifically. This is followed by a discussion of current developments and research in alternative and blended fuels discussed again in both general and specific settings. Key factors and technical considerations for heavy haul applications are reviewed followed by a discussion of non-technical and human factors that motivate a move toward clean energy in North American Heavy Haul systems. Finally current project activities are described to provide a clear understanding of both the status and trajectory of hybrid and hydrogen technologies in the established context.
Estimation of Liquid Hydrogen Fuels in Aviation
Sep 2022
Publication
As the demand for alternative fuels to solve environmental problems increases worldwide due to the greenhouse gas problem this study predicted the demand for liquid hydrogen fuel in aviation to achieve ‘zero‐emission flight’. The liquid hydrogen fuel models of an aircraft and all aviation sectors were produced based on the prediction of aviation fleet growth through the classification of currently operated aircraft. Using these models the required amount of liquid hydrogen fuel and the total cost of liquid hydrogen were also calculated when various environmental regulations were satisfied. As a result it was found to be necessary to convert approximately 66% to 100% of all aircraft from existing aircraft to liquid hydrogen aircraft in 2050 according to regulations. The annual liquid hydrogen cost was 4.7–5.2 times higher in the beginning due to the high production cost but after 2030 it will be maintained at almost the same price and it was found that the cost was rather low compared to jet fuel.
CO2 Emissions of Battery Electric Vehicles and Hydrogen Fuel Cell Vehicles
Jun 2023
Publication
During the last few years electric and hydrogen vehicles have become an alternative to cars that use internal combustion engines. The number of electric and hydrogen vehicles sold has increased due to support from local governments and because car manufacturers will stop the production of internal combustion engines in the near future. The emissions of these vehicles while being driven are zero but they still have an impact on the environment due to their fuel. In this article an analysis of carbon dioxide (CO2 ) emissions for two types of vehicles: battery electric vehicles (BEVs) powered by electricity and fuel cell electric vehicles (FCEVs) powered by hydrogen is presented. The analysis considers different values for the mix of power generation and hydrogen production options in comparison to other studies. The CO2 emissions were calculated and compared for the two types of vehicles. The results show that the CO2 emissions of BEVs are lower when compared to FCEVs if the hydrogen is obtained from pollutant sources and is higher if the hydrogen is obtained from nuclear power and renewable energy sources. When compared to conventional combustion engine vehicles BEVs have lower CO2 emissions while the emissions of FCEVs are dependent on the hydrogen production method.
The Role of Hydrogen for Deep Decarbonization of Energy Systems: A Chilean Case Study
Mar 2023
Publication
In this paper we implement a long-term multi-sectoral energy planning model to evaluate the role of green hydrogen in the energy mix of Chile a country with a high renewable potential under stringent emission reduction objectives in 2050. Our results show that green hydrogen is a cost-effective and environmentally friendly route especially for hard-to-abate sectors such as interprovincial and freight transport. They also suggest a strong synergy of hydrogen with electricity generation from renewable sources. Our numerical simulations show that Chile should (i) start immediately to develop hydrogen production through electrolyzers all along the country (ii) keep investing in wind and solar generation capacities ensuring a low cost hydrogen production and reinforce the power transmission grid to allow nodal hydrogen production (iii) foster the use of electric mobility for cars and local buses and of hydrogen for long-haul trucks and interprovincial buses and (iv) develop seasonal hydrogen storage and hydrogen cells to be exploited for electricity supply especially for the most stringent emission reduction objectives.
Ammonia Decomposition in the Process Chain for a Renewable Hydrogen Supply
Jun 2022
Publication
This review article deals with the challenge to identify catalyst materials from literature studies for the ammonia decomposition reaction with potential for application in large-scale industrial processes. On the one hand the requirements on the catalyst are quite demanding. Of central importance are the conditions for the primary reaction that have to be met by the catalyst. Likewise the catalytic performance i.e. an ideally quantitative conversion and a high lifetime are critical as well as the consideration of requirements on the product properties in terms of pressure or by-products for potential follow-up processes in this case synthesis gas applications. On the other hand the evaluation of the multitude of literature studies poses difficulties due to significant varieties in catalytic testing protocols.
Hydrogen Leakage Simulation and Risk Analysis of Hydrogen Fueling Station in China
Sep 2022
Publication
Hydrogen is a renewable energy source with various features clean carbon-free high energy density which is being recognized internationally as a “future energy.” The US the EU Japan South Korea China and other countries or regions are gradually clarifying the development position of hydrogen. The rapid development of the hydrogen energy industry requires more hydrogenation infrastructure to meet the hydrogenation need of hydrogen fuel cell vehicles. Nevertheless due to the frequent occurrence of hydrogen infrastructure accidents their safety has become an obstacle to large-scale construction. This paper analyzed five sizes (diameters of 0.068 mm 0.215 mm 0.68 mm 2.15 mm and 6.8 mm) of hydrogen leakage in the hydrogen fueling station using Quantitative Risk Assessment (QRA) and HyRAM software. The results show that unignited leaks occur most frequently; leaks caused by flanges valves instruments compressors and filters occur more frequently; and the risk indicator of thermal radiation accident and structure collapse accident caused by over-pressure exceeds the Chinese individual acceptable risk standard and the risk indicator of a thermal radiation accident and head impact accident caused by overpressure is below the Chinese standard. On the other hand we simulated the consequences of hydrogen leak from the 45 MPa hydrogen storage vessels by the physic module of HyRAM and obtained the ranges of plume dispersion jet fire radiative heat flux and unconfined overpressure. We suggest targeted preventive measures and safety distance to provide references for hydrogen fueling stations’ safe construction and operation.
Hydrogen or Electric Drive—Inconvenient (Omitted) Aspects
May 2023
Publication
Currently hydrogen and electric drives used in various means of transport is a leading topic in many respects. This article discusses the most important aspects of the operation of vehicles with electric drives (passenger cars) and hydrogen drives. In both cases the official reason for using both drives is the possibility of independence from fossil fuel supplies especially oil. The desire for independence is mainly dictated by political considerations. This article discusses the acquisition of basic raw materials for the construction of lithium-ion batteries in electric cars as well as methods for obtaining hydrogen as a fuel. The widespread use of electric passenger cars requires the construction of a network of charging stations. This article shows that taking into account the entire production process of electric cars including lithium-ion batteries the argument that they are ecological cannot be used. Additionally it was indicated that there is no concept for the use of used accumulator batteries. If hydrogen drives are used in trains there is no need to build the traction network infrastructure and then continuously monitor its technical condition and perform the necessary repairs. Of course the necessary hydrogen tanks must be built but there must be similar tanks to store oil for diesel locomotives. This paper also deals with other possibilities of hydrogen application for transformational usage e.g. the use of combustion engines driven with liquid hydrogen. Unfortunately an optimistic approach to this issue does not allow for a critical view of the whole matter. In public discussion there is no room for scientific arguments and emotions to dominate.
Can Africa Serve Europe with Hydrogen Energy from Its Renewables?—Assessing the Economics of Shipping Hydrogen and Hydrogen Carriers to Europe from Different Parts of the Continent
Apr 2023
Publication
There exists no single optimal way for transporting hydrogen and other hydrogen carriers from one port to the other globally. Its delivery depends on several factors such as the quantity distance economics and the availability of the required infrastructure for its transportation. Europe has a strategy to invest in the production of green hydrogen in Africa to meet its needs. This study assessed the economic viability of shipping liquefied hydrogen (LH2 ) and hydrogen carriers to Germany from six African countries that have been identified as countries with great potential in the production of hydrogen. The results obtained suggest that the shipping of LH2 to Europe (Germany) will cost between 0.47 and 1.55 USD/kg H2 depending on the distance of travel for the ship. Similarly the transportation of hydrogen carriers could range from 0.19 to 0.55 USD/kg H2 for ammonia 0.25 to 0.77 USD/kg H2 for LNG 0.24 to 0.73 USD/kg H2 for methanol and 0.43 to 1.28 USD/kg H2 for liquid organic hydrogen carriers (LOHCs). Ammonia was found to be the ideal hydrogen carrier since it recorded the least transportation cost. A sensitivity analysis conducted indicates that an increase in the economic life by 5 years could averagely decrease the cost of LNG by some 13.9% NH3 by 13.2% methanol by 7.9% LOHC by 8.03% and LH2 by 12.41% under a constant distance of 6470 nautical miles. The study concludes with a suggestion that if both foreign and local participation in the development of the hydrogen market is increased in Africa the continent could supply LH2 and other hydrogen carriers to Europe at a cheaper price using clean fuel.
Life Cycle Assessment of Carbon Footprint in Public Transportation - A Case Study of Bus Route NO. 2 in Tainan City, Taiwan
Apr 2019
Publication
Human activities have exacerbated global greenhouse effects resulting in extreme climate changes that have caused disasters and food and water shortages in recent years. Transport activities are the one of the main causes of global greenhouse gas (GHG) emissions. Therefore policy makers must develop some strategies to reduce GHG emissions. One of the Taiwan’s transportation policies intended to reduce CO2 emissions is to replace all traditional diesel fuel urban buses with alternative energy buses. This paper uses a case study of bus route NO. 2 in Tainan City and follows the international standard ISO/TS 14067 and PAS2050 to measure the carbon footprints of different energy buses. The purpose is to measure the environmental benefits of alternative energy buses. The results of the bus carbon footprints from high to low were LNG buses 63.14g CO2e/pkm; traditional diesel buses 54.6g CO2e/pkm; liquefied petroleum gas buses 47.4g CO2e/pkm; plug-in electric buses 37.82g CO2e/pkm and hydrogen fuel cell bus es 29.17g CO2e/pkm respectively. It was also found that the use of hydrogen fuel cell buses would potentially reduce CO2e emissions in Tainan City by 1244081 tons which at this time is only city bus No. 2. If all the Taiwan city buses were switched to hydrogen fuel cell buses this would potentially reduce CO2e by 227832.39 tons. The effect of the reduction in carbon emissions from the use of hydrogen fuel cells buses in all Taiwanese urban areas is the equivalent of planting 22.78 million trees. It is thus suggested that the government use hydrogen fuel cell buses as the future of the country’s major alternative energy buses since they are the most environmentally friendly alternative to reducing CO2 emissions.
Identifying Informed Beliefs about Hydrogen Technologies Across the Energy Supply Chain
Apr 2023
Publication
Developing a thriving hydrogen industry will depend on public and community support. Past research mainly focusing on the acceptance of hydrogen fuelling stations and cars suggests that people generally support hydrogen energy technology (HET). Few studies have however considered how people think about other components of the hydrogen supply chain (i.e. technologies required to make store transport and use hydrogen). Moreover there has been limited research investigating how people interpret and develop beliefs about HET after being presented with technical information. This paper attempts to address these research gaps by presenting the findings from four face-to-face focus group discussions conducted in Australia. The findings suggest that people have differing views about HET which depends on the type of technology and these views influence levels of support. The study also revealed concerns about a range of other factors that have yet to be considered in hydrogen acceptance research (e.g. perceived water use efficiency and indirect benefits). The findings highlight the value of qualitative research for identifying salient beliefs that shape attitudes towards HET and provide recommendations for future research and how to effectively communicate with the public and communities about an emerging hydrogen industry.
Economic Assessment of Hydrogen Production in a Renewable Energy Community in Italy
Feb 2023
Publication
Renewable Energy Community (REC) is a new paradigm in European Union to produce transform share and sell renewables at a local consumer level also via e-fuel (i.e. hydrogen). This work investigates the economic feasibility of a hydrogen Power-to-Gas (PtG) system realized inside a REC using only excess renewable electricity not consumed by REC itself. A single centralized photovoltaic (PV) plant is directly connected to an electrolyser; a hydrogen compressor and two hydrogen storages at low and high pressure complete the PtG system. A scenario of a REC composed by 450 residential electric users (around 1000 people) has been analysed coupled with described PtG considering eight different sizes of PV plant. In the study Italian subsidies to REC shared energy are evaluated as incentives to hydrogen production. An optimal size of PtG components for each PV size is investigated at the limit of economical sustainability evaluating net present value (NPV) positive and near zero. Results show that for the considered REC it is possible to produce and sell up to around 3 tons per year of green hydrogen at most to the same lowest selling price declared currently in the Italian market (5 €/kg).
Review and Comparison of Worldwide Hydrogen Activities in the Rail Sector with Special Focus on On-board Storage and Refueling Technologies
Aug 2022
Publication
"This paper investigates hydrogen storage and refueling technologies that were used in rail vehicles over the past 20 years as well as planned activities as part of demonstration projects or feasibility studies. Presented are details of the currently available technology and its vehicle integration market availability as well as standardization and research and development activities. A total of 80 international studies corporate announcements as well as vehicle and refueling demonstration projects were evaluated with regard to storage and refueling technology pressure level hydrogen amount and installation concepts inside rolling stock. Furthermore current hydrogen storage systems of worldwide manufacturers were analyzed in terms of technical data.<br/>We found that large fleets of hydrogen-fueled passenger railcars are currently being commissioned or are about to enter service along with many more vehicles on order worldwide. 35 MPa compressed gaseous storage system technology currently dominates in implementation projects. In terms of hydrogen storage requirements for railcars sufficient energy content and range are not a major barrier at present (assuming enough installation space is available). For this reason also hydrogen refueling stations required for 35 MPa vehicle operation are currently being set up worldwide.<br/>A wide variety of hydrogen demonstration and retrofit projects are currently underway for freight locomotive applications around the world in addition to completed and ongoing feasibility studies. Up to now no prevailing hydrogen storage technology emerged especially because line-haul locomotives are required to carry significantly more energy than passenger trains. The 35 MPa compressed storage systems commonly used in passenger trains offer too little energy density for mainline locomotive operation - alternative storage technologies are not yet established. Energy tender solutions could be an option to increase hydrogen storage capacity here."
Energy-Economic Assessment of Islanded Microgrid with Wind Turbine, Photovoltaic Field, Wood Gasifier, Battery, and Hydrogen Energy Storage
Sep 2022
Publication
Island energy systems are becoming an important part of energy transformation due to the growing needs for the penetration of renewable energy. Among the possible systems a combination of different energy generation technologies is a viable option for local users as long as energy storage is implemented. The presented paper describes an energy-economic assessment of an island system with a photovoltaic field small wind turbine wood chip gasifier battery and hydrogen circuit with electrolyzer and fuel cell. The system is designed to satisfy the electrical energy demand of a tourist facility in two European localizations. The operation of the system is developed and dynamically simulated in the Transient System Simulation (TRNSYS) environment taking into account realistic user demand. The results show that in Gdansk Poland it is possible to satisfy 99% of user demand with renewable energy sources with excess energy equal to 31% while in Agkistro Greece a similar result is possible with 43% of excess energy. Despite the high initial costs it is possible to obtain Simple Pay Back periods of 12.5 and 22.5 years for Gdansk and Agkistro respectively. This result points out that under a high share of renewables in the energy demand of the user the profitability of the system is highly affected by the local cost of energy vectors. The achieved results show that the system is robust in providing energy to the users and that future development may lead to an operation based fully on renewables.
Efficiency, Economic and Environmental Impact Assessment of a Newly Developed Rail Engine using Hydrogen and Other Sustainable Fuel Blends
Jan 2023
Publication
Locomotives still use antiqued engines such as internal combustion engines operated by fossil fuels which cause global warming due to their significant emissions. This paper continues investigating the newly hybridized locomotive engine containing a gas turbine system solid oxide fuel cell system energy saving system and on-board hydrogen production system. This new engine is operated using five fuel blends composed of five alternative fuels such as hydrogen methane methanol ethanol and dimethyl ether. The current investigation involves exergy analysis exergo-economic analysis and exergo-environmental analysis to assess the engine from three perspectives: efficiency/irreversibility cost and environmental impact. The study results show that the net power of this new engine is 4948.6 kW and it has an exergetic efficiency of 62.7% according to the fuel and product principle. This engine weighs about 9 tons and costs about $10.2M with a levelized cost rate of 147 $/h and 14.06 mPt/h of overall component-related environmental rate. The average overall specific fuel and product exergy costs are about 37 $/GJ and 60 $/GJ and the minimum values are 13.3 $/GJ and 21.8 $/GJ using methane and hydrogen blend respectively. Also the average overall specific fuel and product exergo-environmental impact are about 15 and 23 mPt/MJ respectively. The on-board hydrogen production has an average exergy cost of 274 $/GJ and an environmental impact of 52 mPt/MJ. Hydrogen blended with methane or methanol is found to be more economic and has less environmental impact.
A Review of the Role of Hydrogen in the Heat Decarbonization of Future Energy Systems: Insights and Perspectives
Apr 2024
Publication
Hydrogen is an emerging technology changing the context of heating with cleaner combustion than traditional fossil fuels. Studies indicate the potential to repurpose the existing natural gas infrastructure offering consumers a sustainable economically viable option in the future. The integration of hydrogen in combined heat and power systems could provide residential energy demand and reduce environmental emissions. However the widespread adoption of hydrogen will face several challenges such as carbon dioxide emissions from the current production methods and the need for infrastructure modification for transport and safety. Researchers indicated the viability of hydrogen in decarbonizing heat while some studies also challenged its long-term role in the future of heating. In this paper a comprehensive literature review is carried out by identifying the following key aspects which could impact the conclusion on the overall role of hydrogen in heat decarbonization: (i) a holistic view of the energy system considering factors such as renewable integration and system balancing; (ii) consumer-oriented approaches often overlook the broader benefits of hydrogen in emission reduction and grid stability; (iii) carbon capture and storage scalability is a key factor for large-scale production of low-emission blue hydrogen; (iv) technological improvements could increase the cost-effectiveness of hydrogen; (v) the role of hydrogen in enhancing resilience especially during extreme weather conditions raises the potential of hydrogen as a flexible asset in the energy infrastructure for future energy supply; and finally when considering the UK as a basis case (vi) incorporating factors such as the extensive gas network and unique climate conditions necessitates specific strategies.
Prospects of Fuel Cell Combined Heat and Power Systems
Aug 2020
Publication
Combined heat and power (CHP) in a single and integrated device is concurrent or synchronized production of many sources of usable power typically electric as well as thermal. Integrating combined heat and power systems in today’s energy market will address energy scarcity global warming as well as energy-saving problems. This review highlights the system design for fuel cell CHP technologies. Key among the components discussed was the type of fuel cell stack capable of generating the maximum performance of the entire system. The type of fuel processor used was also noted to influence the systemic performance coupled with its longevity. Other components equally discussed was the power electronics. The thermal and water management was also noted to have an effect on the overall efficiency of the system. Carbon dioxide emission reduction reduction of electricity cost and grid independence were some notable advantages associated with fueling cell combined heat and power systems. Despite these merits the high initial capital cost is a key factor impeding its commercialization. It is therefore imperative that future research activities are geared towards the development of novel and cheap materials for the development of the fuel cell which will transcend into a total reduction of the entire system. Similarly robust systemic designs should equally be an active research direction. Other types of fuel aside hydrogen should equally be explored. Proper risk assessment strategies and documentation will similarly expand and accelerate the commercialization of this novel technology. Finally public sensitization of the technology will also make its acceptance and possible competition with existing forms of energy generation feasible. The work in summary showed that proton exchange membrane fuel cell (PEM fuel cell) operated at a lower temperature-oriented cogeneration has good efficiency and is very reliable. The critical issue pertaining to these systems has to do with the complication associated with water treatment. This implies that the balance of the plant would be significantly affected; likewise the purity of the gas is crucial in the performance of the system. An alternative to these systems is the PEM fuel cell systems operated at higher temperatures.
Green Steel: Synergies between the Australian Iron Ore Industry and the Production of Green Industry
May 2023
Publication
Green steel produced using renewable energy and hydrogen presents a promising avenue to decarbonize steel manufacturing and expand the hydrogen industry. Australia endowed with abundant renewable resources and iron ore deposits is ideally placed to support this global effort. This paper's two-step analytical approach offers the first comprehensive assessment of Australia's potential to develop green steel as a value-added export commodity. The Economic Fairways modelling reveals a strong alignment between prospective hydrogen hubs and current and future iron ore operations enabling shared infrastructure development and first-mover advantages. By employing a site-based system optimization that integrates both wind and solar power sources the cost of producing green steel could decrease significantly to around AU$900 per tonne by 2030 and AU$750 per tonne by 2050. Moreover replacing 1% of global steel production would require 35 GW of well-optimized wind and solar photovoltaics 11 GW of hydrogen electrolysers and 1000 square kilometres of land. Sensitivity analysis further indicates that iron ore prices would exert a long-term influence on green steel prices. Overall this study highlights the opportunities and challenges facing the Australian iron ore industry in contributing to the decarbonization of the global steel sector underscoring the crucial role of government support in driving the growth and development of the green steel industry.
Study on Hydrogen in Ports and Industrial Coastal Areas - Report 1
Jan 2023
Publication
The study feeds into the work of the Global Hydrogen Ports Coalition launched at the latest Clean Energy Ministerial (CEM12). This important international initiative brings together ports from around the world to work together on hydrogen technologies. The planned study will be a comprehensive assessment of the hydrogen demand in ports and industrial coastal areas enabling the creation of a 'European Hydrogen Ports Roadmap'. It will also feature clear economic forecasts based on a variety of business models for the transition to renewable hydrogen in ports while presenting new case studies and project concepts. “The objective is to provide new directions for research and innovation guidance for regulation codes and standards and proposals on policy and regulation. The forthcoming study will also help create impetus for stakeholders to come together and take a long term perspective on the hydrogen transition in ports. Finally the study will be a centralized resource It will form a Europe wide hydrogen ports ' when combined with roadmaps and other materials created by individual ports.
Assessment of the Co-combustion Process of Ammonia with Hydrogen in a Research VCR Piston Engine
Oct 2022
Publication
The presented work concerns experimental research of a spark-ignition engine with variable compression ratio (VCR) adapted to dual-fuel operation in which co-combustion of ammonia with hydrogen was conducted and the energy share of hydrogen varied from 0% to 70%. The research was aimed at assessing the impact of the energy share of hydrogen co-combusted with ammonia on the performance stability and emissions of an engine operating at a compression ratio of 8 (CR 8) and 10 (CR 10). The operation of the engine powered by ammonia alone for both CR 8 and CR 10 is associated with either a complete lack of ignition in a significant number of cycles or with significantly delayed ignition and the related low value of the maximum pressure pmax. Increasing the energy share of hydrogen in the fuel to 12% allows to completely eliminate the instability of the ignition process in the combustible mixture which is confirmed by a decrease in the IMEP uniqueness and a much lower pmax dispersion. For 12% of the energy share of hydrogen co-combusted with ammonia the most favorable course of the combustion process was obtained the highest engine efficiency and the highest IMEP value were recorded. The conducted research shows that increasing the H2 share causes an increase in NO emissions for both analyzed compression ratios
Optimized Design and Control of an Off Grid solar PV/hydrogen Fuel Cell Power System for Green Buildings
Sep 2017
Publication
Modelling simulation optimization and control strategies are used in this study to design a stand-alone solar PV/Fuel Cell/Battery/Generator hybrid power system to serve the electrical load of a commercial building. The main objective is to design an off grid energy system to meet the desired electric load of the commercial building with high renewable fraction low emissions and low cost of energy. The goal is to manage the energy consumption of the building reduce the associate cost and to switch from grid-tied fossil fuel power system to an off grid renewable and cleaner power system. Energy audit was performed in this study to determine the energy consumption of the building. Hourly simulations modelling and optimization were performed to determine the performance and cost of the hybrid power configurations using different control strategies. The results show that the hybrid off grid solar PV/Fuel Cell/Generator/Battery/Inverter power system offers the best performance for the tested system architectures. From the total energy generated from the off grid hybrid power system 73% is produced from the solar PV 24% from the fuel cell and 3% from the backup Diesel generator. The produced power is used to meet all the AC load of the building without power shortage (<0.1%). The hybrid power system produces 18.2% excess power that can be used to serve the thermal load of the building. The proposed hybrid power system is sustainable economically viable and environmentally friendly: High renewable fraction (66.1%) low levelized cost of energy (92 $/MWh) and low carbon dioxide emissions (24 kg CO2/MWh) are achieved.
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