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Everything About Hydrogen Podcast: The Other Hydrogen Vehicle?
Oct 2019
Publication
For this episode we speak to Amanda Lyne the Managing Director of ULEMCo and the Chair of the UK Hydrogen and Fuel Cell Association (UKHFCA). Below are a few links to some of the content discussed on the show and some further background reading.
The podcast can be found on their website
The podcast can be found on their website
A Review on Ports' Readiness to Facilitate International Hydrogen Trade
Jan 2023
Publication
The existing literature on the hydrogen supply chains has knowledge gaps. Most studies focus on hydrogen production storage transport and utilisation but neglect ports which are nexuses in the supply chains. To fill the gap this paper focuses on ports' readiness for the upcoming hydrogen international trade. Potential hydrogen exporting and importing ports are screened. Ports' readiness for hydrogen export and import are reviewed from perspectives of infrastructure risk management public acceptance regulations and standards and education and training. The main findings are: (1) liquid hydrogen ammonia methanol and LOHCs are suitable forms for hydrogen international trade; (2) twenty ports are identified that could be first movers; among them twelve are exporting ports and eight are importing ports; (3) ports’ readiness for hydrogen international trade is still in its infancy and the infrastructure construction or renovation risk management measures establishment of regulations and standards education and training all require further efforts.
Moving Toward the Low-carbon Hydrogen Economy: Experiences and Key Learnings from National Case Studies
Sep 2022
Publication
The urgency to achieve net-zero carbon dioxide (CO2) emissions by 2050 as first presented by the IPCC special report on 1.5°C Global Warming has spurred renewed interest in hydrogen to complement electrification for widespread decarbonization of the economy. We present reflections on estimates of future hydrogen demand optimization of infrastructure for hydrogen production transport and storage development of viable business cases and environmental impact evaluations using life cycle assessments. We highlight challenges and opportunities that are common across studies of the business cases for hydrogen in Germany the UK the Netherlands Switzerland and Norway. The use of hydrogen in the industrial sector is an important driver and could incentivise large-scale hydrogen value chains. In the long-term hydrogen becomes important also for the transport sector. Hydrogen production from natural gas with capture and permanent storage of the produced CO2 (CCS) enables large-scale hydrogen production in the intermediate future and is complementary to hydrogen from renewable power. Furthermore timely establishment of hydrogen and CO2 infrastructures serves as an anchor to support the deployment of carbon dioxide removal technologies such as direct air carbon capture and storage (DACCS) and biohydrogen production with CCS. Significant public support is needed to ensure coordinated planning governance and the establishment of supportive regulatory frameworks which foster the growth of hydrogen markets.
Effect of H2 on Blast Furnace Ironmaking: A Review
Nov 2022
Publication
Under the background of “carbon peaking” and “carbon neutralization” the green transformation of iron and steel enterprises is imminent. The hydrogen-rich smelting technology of blast furnaces is very important for reducing energy consumption and CO2 emission in ironmaking systems and it is one of the important directions of green and low-carbon development of iron and steel enterprises. In this paper the research status of the thermal state reduction mechanism of iron-bearing burden coke degradation behavior and formation of the cohesive zone in various areas of blast furnace after hydrogen-rich smelting is summarized which can make a more clear and comprehensive understanding for the effect of H2 on blast furnace ironmaking. Meanwhile based on the current research situation it is proposed that the following aspects should be further studied in the hydrogen-rich smelting of blast furnaces: (1) the utilization rate of hydrogen and degree of substitution for direct reduction (2) combustion behavior of fuel in raceway (3) control of gas flow distribution in the blast furnace (4) operation optimization of the blast furnace.
Sector Coupling and Business Models Towards Sustainability: The Case of the Hydrogen Vehicle Industry
Mar 2022
Publication
The concept of sector coupling has been gaining increased momentum in political discourses during 18 the past few years but it has only recently received the attention of international academics. The 19 private sector is particularly relevant to foster sector coupling through entrepreneurial action – 20 specifically innovative business models for more sustainable technologies are needed to promote a 21 transition towards more sustainability. So far however the literature on business models from a 22 sector coupling perspective is scarce yet strongly emerging. To address the identified research gaps 23 and enhance the current knowledge on the emerging hydrogen vehicle industry and sector coupling 24 this study adopts a qualitative and exploratory research approach and builds on information gained 25 in 103 semi-structured interviews to discuss emerging business models in Germany. In particular 33 26 business cases have been analyzed. Anchoring business model theory to the concept of sector 27 coupling this study identifies 12 business model archetypes in the emerging hydrogen vehicle 28 industry and its value chain. It can be shown that while the market is still emerging and the market 29 players are not defined and are evolving companies are currently engaged in finding their position 30 along the value chain fostering vertical integration and promoting cooperation between the 31 different sectors. While this study is relevant for both the academia and the industry it is particularly 2 32 interesting for policy makers shaping the future of sustainable development specifically considering 33 integrated energy systems.
Decarbonizing Natural Gas: A Review of Catalytic Decomposition and Carbon Formation Mechanisms
Apr 2022
Publication
In the context of energy conservation and the reduction of CO2 emissions inconsistencies between the inevitable emission of CO2 in traditional hydrogen production methods and eco-friendly targets have become more apparent over time. The catalytic decomposition of methane (CDM) is a novel technology capable of producing hydrogen without releasing CO2 . Since hydrogen produced via CDM is neither blue nor green the term “turquoise” is selected to describe this technology. Notably the by-products of methane cracking are simply carbon deposits with different structures which can offset the cost of hydrogen production cost should they be harvested. However the encapsulation of catalysts by such carbon deposits reduces the contact area between said catalysts and methane throughout the CDM process thereby rendering the continuous production of hydrogen impossible. This paper mainly covers the CDM reaction mechanisms of the three common metal-based catalysts (Ni Co Fe) from experimental and modelling approaches. The by-products of carbon modality and the key parameters that affect the carbon formation mechanisms are also discussed.
Comparative Cost Assessment of Sustainable Energy Carriers Produced from Natural Gas Accounting for Boil-off Gas and Social Cost of Carbon
Jun 2020
Publication
As a result of particular locations of large-scale energy producers and increases in energy demand transporting energy has become one of the key challenges of energy supply. For a long-distance ocean transportation transfer of energy carriers via ocean tankers is considered as a decent solution compared to pipelines. Due to cryogenic temperatures of energy carriers heat leaks into storage tanks of these carriers causes a problem called boil-off gas (BOG). BOG losses reduce the quantity of energy carriers which affects their economic value. Therefore this study proposes to examine the effects of BOG economically in production and transportation phases of potential energy carriers produced from natural gas namely; liquefied natural gas (LNG) dimethyl-ether (DME) methanol liquid ammonia (NH3) and liquid hydrogen (H2). Mathematical approach is used to calculate production and transportation costs of these energy carriers and to account for BOG as a unit cost within the total cost. The results of this study show that transportation costs of LNG liquid ammonia methanol DME and liquid hydrogen from natural gas accounting for BOG are 0.74 $/GJ 1.09 $/GJ 0.68 $/GJ 0.53 $/GJ and 3.24 $/GJ respectively. DME and methanol can be more economic compared to LNG to transport the energy of natural gas for the same ship capacity. Including social cost of carbon (SCC) within the total cost of transporting the energy of natural gas the transportation cost of liquid ammonia is 1.11 $/GJ whereas LNG transportation cost rises significantly to 1.68 $/GJ at SCC of 137 $/t CO2 eq. Consequently liquid ammonia becomes economically favored compared to LNG. Transportation cost of methanol (0.70 $/GJ) and DME (0.55 $/GJ) are also lower than LNG however liquid hydrogen transportation cost (3.24 $/GJ) is still the highest even though the increment of the cost is about 0.1% as SCC included within the transportation cost.
Can Industrial-Scale Solar Hydrogen Supplied from Commodity Technologies Be Cost Competitive by 2030?
Sep 2020
Publication
Expanding decarbonization efforts beyond the power sector are contingent on cost-effective production of energy carriers like H2 with near-zero life-cycle carbon emissions. Here we assess the levelized cost of continuous H2 supply (95% availability) at industrial-scale quantities (100 tonnes/day) in 2030 from integrating commodity technologies for solar photovoltaics electrolysis and energy storage. Our approach relies on modeling the least-cost plant design and operation that optimize component sizes while adhering to hourly solar availability production requirements and component inter-temporal operating constraints. We apply the model to study H2 production costs spanning the continental United States and through extensive sensitivity analysis explore system configurations that can achieve $2.5/kg levelized costs or less for a range of plausible 2030 technology projections at high-irradiance locations. Notably we identify potential sites and system configurations where PV-electrolytic H2 could substitute natural gas-derived H2 at avoided CO2 costs (%$120/ton) similar to the cost of deploying carbon capture and sequestration.
Improving the Economics of Fossil-free Steelmaking via Co-production of Methanol
Mar 2022
Publication
Steelmaking is responsible for 7% of the global net emissions of carbon dioxide and heavily reducing emissions from currently dominating steelmaking processes is difficult and costly. Recently new steelmaking processes based on the reduction of iron ore with hydrogen (H2) produced via water electrolysis have been suggested. If the electricity input to such processes is fossil-free near-zero carbon dioxide emissions steelmaking is achievable. However the high electricity demand of electrolysis is a significant implementation barrier. A H2 storage may alleviate this via allowing a larger share of H2 to be produced at low electricity prices. However accurately forecasting the dynamics of electricity markets is challenging. This increases the risk of investment in a H2 storage. Here we evaluate a novel methanol-based H2 storage concept for a H2-based steelmaking process that also allows for the coproduction of methanol. During electricity price peaks the methanol can be reformed to produce H2 for the steelmaking process. During prolonged periods of low electricity prices excess methanol can be produced and sold off thus improving the prospects of storage profitability. We use historical electricity prices and a process model to evaluate methanol-fossil-free steel co-production schemes. Methanol coproduction has the potential to improve the economics of H2 supply to a fossil-free steelmaking process by up to an average of 0.40 €/kg H2 across considered scenarios equivalent to a reduction in H2 production electricity costs of 25.0%
Hydrogen Production and Carbon Sequestration by Steam Methane Reforming and Fracking with Carbon Dioxide
Feb 2020
Publication
An opportunity to sequester large amounts of carbon dioxide (CO2) is made possible because hydraulic fracturing is used to produce most of America's natural gas. CO2 could be extracted from natural gas and water using steam methane reforming pressurized to its supercritical phase and used instead of water to fracture additional hydrocarbon-bearing rock. The useful energy carrier that remains is hydrogen with carbon returned to the ground. Research on the use of supercritical CO2 is reviewed with proppant entrainment identified as the major area where technical advances may be needed. The large potential for greenhouse-gas reduction through sequestration of CO2 and avoidance of methane leakage from the natural gas system is quantified.
Analysis of Performance, Emissions, and Lubrication in a Spark-ignition Engine Fueled with Hydrogen Gas Mixtures
Oct 2022
Publication
Hydrogen is one of the main alternative fuels with the greatest potential to replace fossil fuels due to its renewable and environmentally friendly nature. Due to this the present investigation aims to evaluate the combustion characteristics performance parameters emissions and variations in the characteristics of the lubricating oil. The investigation was conducted in a spark-ignition engine fueled by gasoline and hydrogen gas. Four engine load conditions (25% 50% 75% and 100%) and three hydrogen gas mass concentration conditions (3% 6% and 9%) were defined for the study. The investigation results allowed to demonstrate that the injection of hydrogen gas in the gasoline engine causes an increase of 3.2% and 4.0% in the maximum values of combustion pressure and heat release rates. Additionally hydrogen causes a 2.9% increase in engine BTE. Hydrogen's more efficient combustion process allowed for reducing CO HC and smoke opacity emissions. However hydrogen gas causes an additional increase of 14.5% and 30.4% in reducing the kinematic viscosity and the total base number of the lubricating oil. In addition there was evidence of an increase in the concentration of wear debris such as Fe and Cu which implies higher rates of wear in the engine's internal components.
HyDeploy2: Summary of Procedures for the Trial Network
Jun 2021
Publication
The assessment of appropriate operational procedures to govern the injection of a hydrogen/natural gas blend into Northern Gas Networks’ (NGN) Winlaton gas distribution network was a key requirement of the HyDeploy2 project. To perform this assessment the review was broken down into two areas procedures upstream of the emergency control valve (owned by NGN) and procedures downstream of the Emergency Control Valve (procedures which would be performed by Gas Safe registered individuals). Assessment of the upstream procedures was led by NGN (own and carry out all upstream procedures on NGN’s gas network) and assessment of the downstream procedures was led by Blue Flame Associates (an industry expert on downstream gas procedures).<br/>Methodologies were adopted to be able to highlight procedures that could potentially be used on the Winlaton trial network during the hydrogen blended gas injection period and if they were impacted by the changing of the gas within the network from natural gas to hydrogen blended gas. This method determined that for downstream gas procedures a total of 56 gas procedures required expert review resulting in 80 technical questions to be assessed and for the upstream gas procedures a total of 80 gas procedures required expert review resulting in 266 technical questions to be assessed.<br/>The operational procedures assessment has led to a determination as to whether a change is or is not required for relevant operational procedures where a basis of concern existed with respect to the injection of hydrogen blended gas. Any requirements to modify an existing procedure has been given in this report referencing the source as to where the detailed analysis for the change/no change recommendation has been given.<br/>The assessment took into account the associated experimental and research carried out as part of the HyDeploy and HyDeploy2 projects such as the assessment of gas characteristics materials impact appliance survey of assets on the Winlaton network and impact of hydrogen blended gas on gas detection equipment references to these studies have been given accordingly to associated impacted operational procedures.<br/>The conclusion of the assessment is that for upstream gas procedures there are some operational procedures that are unchanged some that require an increase in the frequency as to how often they are performed and some procedures which require a technical modification. For downstream domestic gas procedures all procedures applicable to a domestic gas installation were deemed to not be detrimentally affected by the introduction of a 20 mol% hydrogen blend.<br/>For upstream gas procedures an appropriate training package will be built off the back of the results presented in this report and disseminated accordingly to all relevant Operatives that will be responsible for the safety operation and maintenance of the Winlaton network during the hydrogen blend injection period. For downstream gas procedures the Gas Safe community have been fully engaged and informed about the trial.<br/>Click on the supplements tab to view the other documents from this report
A Compilation of Operability and Emissions Performance of Residential Water Heaters Operated on Blends of Natural Gas and Hydrogen Including Consideration for Reporting Bases
Feb 2023
Publication
The impact of hydrogen added to natural gas on the performance of commercial domestic water heating devices has been discussed in several recent papers in the literature. Much of the work focuses on performance at specific hydrogen levels (by volume) up to 20–30% as a near term blend target. In the current work new data on several commercial devices have been obtained to help quantify upper limits based on flashback limits. In addition results from 39 individual devices are compiled to help generalize observations regarding performance. The emphasis of this work is on emissions performance and especially NOx emissions. It is important to consider the reporting bases of the emissions numbers to avoid any unitended bias. For water heaters the trends associated with both mass per fuel energy input and concentration-based representation are similar For carbon free fuels bases such as 12% CO2 should be avoided. In general the compiled data shows that NOx NO UHC and CO levels decrease with increasing hydrogen percentage. The % decrease in NOx and NO is greater for low NOx devices (meaning certified to NOx <10 ng/J using premixing with excess air) compared to conventional devices (“pancake burners” partial premixing). Further low NOx devices appear to be able to accept greater amounts of hydrogen above 70% hydrogen in some cases without modification while conventional water heaters appear limited to 40–50% hydrogen. Reporting emissions on a mass basis per unit fuel energy input is preferred to the typical dry concentration basis as the greater amount of water produced by hydrogen results in a perceived increase in NOx when hydrogen is used. While this effort summarizes emissions performance with added hydrogen additional work is needed on transient operation higher levels of hydrogen system durability/reliability and heating efficiency.
Comparative Sustainability Study of Energy Storage Technologies Using Data Envelopment Analysis
Mar 2022
Publication
The transition to energy systems with a high share of renewable energy depends on the availability of technologies that can connect the physical distances or bridge the time differences between the energy supply and demand points. This study focuses on energy storage technologies due to their expected role in liberating the energy sector from fossil fuels and facilitating the penetration of intermittent renewable sources. The performance of 27 energy storage alternatives is compared considering sustainability aspects by means of data envelopment analysis. To this end storage alternatives are first classified into two clusters: fast-response and long-term. The levelized cost of energy energy and water consumption global warming potential and employment are common indicators considered for both clusters while energy density is used only for fast-response technologies where it plays a key role in technology selection. Flywheel reveals the highest efficiency between all the fast-response technologies while green ammonia powered with solar energy ranks first for long-term energy storage. An uncertainty analysis is incorporated to discuss the reliability of the results. Overall results obtained and guidelines provided can be helpful for both decision-making and research and development purposes. For the former we identify the most appealing energy storage options to be promoted while for the latter we report quantitative improvement targets that would make inefficient technologies competitive if attained. This contribution paves the way for more comprehensive studies in the context of energy storage by presenting a powerful framework for comparing options according to multiple sustainability indicators.
Progress of Performance, Emission, and Technical Measures of Hydrogen Fuel Internal-Combustion Engines
Oct 2022
Publication
To achieve the goals of low carbon emission and carbon neutrality some urgent challenges include the development and utilization of low-carbon or zero-carbon internal combustion engine fuels. Hydrogen as a clean efficient and sustainable fuel has the potential to meet the abovementioned challenges. Thereby hydrogen internal combustion engines have been attracting attention because of their zero carbon emissions high thermal efficiency high reliability and low cost. In this paper the opportunities and challenges faced by hydrogen internal-combustion engines were analyzed. The progress of hydrogen internal-combustion engines on the mixture formation combustion mode emission reduction knock formation mechanism and knock suppression measures were summarized. Moreover possible technical measures for hydrogen internal-combustion engines to achieve higher efficiency and lower emissions were suggested.
Contribution of Potential Clean Trucks in Carbon Peak Pathway of Road Freight Based on Scenario Analysis: A Case Study of China
Oct 2022
Publication
Reducing the carbon emissions from trucks is critical to achieving the carbon peak of road freight. Based on the prediction of truck population and well-to-wheel (WTW) emission analysis of traditional diesel trucks and potential clean trucks including natural gas battery-electric plug-in hybrid electric and hydrogen fuel cell the paper analyzed the total greenhouse gas (GHG) emissions of China's road freight under four scenarios including baseline policy facilitation (PF) technology breakthrough (TB) and PF-TB. The truck population from 2021 to 2035 is predicted based on regression analysis by selecting the data from 2002 to 2020 of the main variables such as the GDP scale road freight turnover road freight volume and the number of trucks. The study forecasts the truck population of different segments such as mini-duty trucks (MiDT) light-duty trucks (LDT) medium-duty trucks (MDT) and heavy-duty trucks (HDT). Relevant WTW emissions data are collected and adopted based on the popular truck in China's market PHEVs have better emission intensity especially in the HDT field which reduces by 51% compared with ICEVs. Results show that the scenario of TB and PF-TB can reach the carbon peak with 0.13% and 1.5% total GHG emissions reduction per year. In contrast the baseline and PF scenario fail the carbon peak due to only focusing on the number of clean trucks while lacking the restrictions on the GHG emission factors of energy and ignoring the improvement of trucks' energy efficiency and the total emissions increased by 29.76% and 16.69% respectively compared with 2020. As the insights adopting clean trucks has an important but limited effect which should coordinate with the transition to low carbon energy and the melioration of clean trucks to reach the carbon peak of road freight in China.
Numerical Simulation of Hydrogen Deflagration Using CFD
Sep 2021
Publication
Hydrogen is seen as an important future energy carrier as part of the move away from traditional hydrocarbon sources. Delayed ignition of a hydrogen-air mixture formed from an accidental release of hydrogen in either a confined or congested environment can lead to the generation of overpressure impacting both people and assets. An understanding of the possible overpressures generated is critical in designing facilities and effective mitigation systems against hydrogen explosion hazards. This paper describes the numerical modelling of hydrogen deflagrations using a new application PDRFOAM-R that is part of the wider OpenFOAM open-source CFD package of routines for the solution of systems of partial differential equations. The PDRFOAM-R code solves momentum and continuity equations the combustion model is based on flame area transport and the turbulent burning velocity correlation is based on Markstein and Karlovitz numbers. PDRFOAM-R is derived from publicly available PDRFOAM tool and it resolves small and large obstacles unlike PDRFOAM which is based on the Porosity Distributed Resistance approach. The PDRFOAM-R code is validated against various unconfined-uncongested and semi-confined congested explosion experiments. The flame dynamics and pressure history predicted from the simulation show a reasonable comparison with the experiments.
Critical Materials in PEMFC Systems and a LCA Analysis for the Potential Reduction of Environmental Impacts with EoL Strategies
Jul 2019
Publication
Commonly used materials constituting the core components of polymer electrolyte membrane fuel cells (PEMFCs) including the balance‐of‐plant were classified according to the EU criticality methodology with an additional assessment of hazardousness and price. A life‐cycle assessment (LCA) of the materials potentially present in PEMFC systems was performed for 1 g of each material. To demonstrate the importance of appropriate actions at the end of life (EoL) for critical materials a LCA study of the whole life cycle for a 1‐kW PEMFC system and 20000 operating hours was performed. In addition to the manufacturing phase four different scenarios of hydrogen production were analyzed. In the EoL phase recycling was used as a primary strategy with energy extraction and landfill as the second and third. The environmental impacts for 1 g of material show that platinum group metals and precious metals have by far the largest environmental impact; therefore it is necessary to pay special attention to these materials in the EoL phase. The LCA results for the 1‐kW PEMFC system show that in the manufacturing phase the major environmental impacts come from the fuel cell stack where the majority of the critical materials are used. Analysis shows that only 0.75 g of platinum in the manufacturing phase contributes on average 60% of the total environmental impacts of the manufacturing phase. In the operating phase environmentally sounder scenarios are the hydrogen production with water electrolysis using hydroelectricity and natural gas reforming. These two scenarios have lower absolute values for the environmental impact indicators on average compared with the manufacturing phase of the 1‐kW PEMFC system. With proper recycling strategies in the EoL phase for each material and by paying a lot of attention to the critical materials the environmental impacts could be reduced on average by 37.3% for the manufacturing phase and 23.7% for the entire life cycle of the 1‐kW PEMFC system.
Exploring Supply Chain Design and Expansion Planning of China's Green Ammonia Production with an Optimization-based Simulation Approach
Aug 2021
Publication
Green ammonia production as an important application for propelling the upcoming hydrogen economy has not been paid much attention by China the world's largest ammonia producer. As a result related studies are limited. This paper explores potential supply chain design and planning strategies of green ammonia production in the next decade of China with a case study in Inner Mongolia. A hybrid optimization-based simulation approach is applied considering traditional optimization approaches are insufficient to address uncertainties and dynamics in a long-term energy transition. Results show that the production cost of green ammonia will be at least twice that of the current level due to higher costs of hydrogen supply. Production accounts for the largest share of the total expense of green hydrogen (~80 %). The decline of electricity and electrolyser prices are key in driving down the overall costs. In addition by-product oxygen is also considered in the model to assess its economic benefits. We found that by-product oxygen sales could partly reduce the total expense of green hydrogen (~12 % at a price of USD 85/t) but it also should be noted that the volatile price of oxygen may pose uncertainties and risks to the effectiveness of the offset. Since the case study may represent the favourable conditions in China due to the abundant renewable energy resources and large-scale ammonia industry in this region we propose to take a moderate step towards green ammonia production and policies should be focused on reducing the electricity price and capital investments in green hydrogen production. We assume the findings and implications are informative to planning future green ammonia production in China.
Transient Modeling and Performance Analysis of Hydrogen-Fueled Aero Engines
Jan 2023
Publication
With the combustor burning hydrogen as well as the strongly coupled fuel and cooling system the configuration of a hydrogen-fueled aero engine is more complex than that of a conventional aero engine. The performance and especially the dynamic behavior of a hydrogen-fueled aero engine need to be fully understood for engine system design and optimization. In this paper both the transient modeling and performance analysis of hydrogen-fueled engines are presented. Firstly the models specific to the hydrogen-fueled engine components and systems including the hydrogen-fueled combustor the steam injection system a simplified model for a quick NOx emission assessment and the heat exchangers are developed and then integrated to a conventional engine models. The simulations with both Simulink and Speedgoat-based hardware in the loop system are carried out. Secondly the performance analysis is performed for a typical turbofan engine configuration CF6 and for the two hydrogen-fueled engine configurations ENABLEH2 and HySIITE which are currently under research and development by the European Union and Pratt & Whitney respectively. At last the simulation results demonstrate that the developed transient models can effectively reflect the characteristics of hydrogen burning heat exchanging and NOx emission for hydrogen-fueled engines. In most cases the hydrogen-fueled engines show lower specific fuel consumption lower turbine entry temperature and less NOx emissions compared with conventional engines. For example at max thrust state the advanced hydrogen-fueled engine can reduce the parameters mentioned above by about 68.5% 3.7% and 12.7% respectively (a mean value of two configurations).
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