Finland

Green hydrogen is a tentative solution for the decarbonisation of hard-to-abate sectors such as steel chemical cement and refinery industries. Green hydrogen is a form of hydrogen gas that is produced using renewable energy sources such as wind or solar power through a process called electrolysis. The green hydrogen supply chain includes several interconnected entities such as renewable energy providers electrolysers distribution facilities and consumers. Although there have been many studies about green hydrogen little attention has been devoted to green hydrogen supply chain risk identification and analysis especially for hard-to-abate sectors in Europe. This research contributes to existing knowledge by identifying and analysing the European region’s green hydrogen supply chain risk factors. Using a Delphi method 7 categories and 43 risk factors are identified based on the green hydrogen supply chain experts’ opinions. The best-worst method is utilised to determine the importance weights of the risk categories and risk factors. High investment of capital for hydrogen production and delivery technology was the highest-ranked risk factor followed by the lack of enough capacity for electrolyser and policy & regulation development. Several mitigation strategies and policy recommendations are proposed for high-importance risk factors. This study provides novelty in the form of an integrated approach resulting in a scientific ranking of the risk factors for the green hydrogen supply chain. The results of this study provide empirical evidence which corroborates with previous studies that European countries should endeavour to create comprehensive and supportive standards and regulations for green hydrogen supply chain implementation.

A clean energy revolution is occurring across the world. As iron and steelmaking have a tremendous impact on the amount of CO2 emissions there is an increasing attraction towards improving the green footprint of iron and steel production. Among reducing agents hydrogen has shown a great potential to be replaced with fossil fuels and to decarbonize the steelmaking processes. Although hydrogen is in great supply on earth extracting pure H2 from its compound is costly. Therefore it is crucial to calculate the partial pressure of H2 with the aid of reduction reaction kinetics to limit the costs. This review summarizes the studies of critical parameters to determine the kinetics of reduction. The variables considered were temperature iron ore type (magnetite hematite goethite) H2/CO ratio porosity flow rate the concentration of diluent (He Ar N2 ) gas utility annealing before reduction and pressure. In fact increasing temperature H2/CO ratio hydrogen flow rate and hematite percentage in feed leads to a higher reduction rate. In addition the controlling kinetics models and the impact of the mentioned parameters on them investigated and compared concluding chemical reaction at the interfaces and diffusion of hydrogen through the iron oxide particle are the most common kinetics controlling models.

The hydrogen economy will play a key role in future energy systems. Several thermal and catalytic methods for hydrogen production have been presented. In this review methane thermocatalytic and thermal decomposition into hydrogen gas and solid carbon are considered. These processes known as the thermal decomposition of methane (TDM) and thermocatalytic decomposition (TCD) of methane respectively appear to have the greatest potential for hydrogen production. In particular the focus is on the different types and properties of carbons formed during the decomposition processes. The applications for carbons are also investigated.

A comprehensive investigation on diesel pilot spray ignited methane-hydrogen (CH₄–H₂) combustion tri-fuel combustion (TF) is performed in a single-cylinder compression ignition (CI) engine. The experiments provide a detailed analysis of the effect of H₂ concentration (based on mole fraction M_H2) and charge-air temperature (Tair) on the ignition behavior combustion stability cycle-to-cycle (CCV) and engine performance. The results indicate that adding H₂ from 0 to 60% shortens the ignition delay time (IDT) and combustion duration (based on CA90) up to 33% and 45% respectively. Thereby H₂ helps to increase the indicated thermal efficiency (ITE) by as much as 10%. Furthermore to gain an insight into the combustion stability and CCV the short-time Fourier transform (STFT) and continuous wavelet transform (CWT) methodologies are applied to estimate the combustion stability and CCV of the TF combustion process. The results reveal that the pressure oscillation can be reduced up to 4 dB/Hz and the CCV by 50% when M_H2 < 60% and Tair < 55 °C. However when M_H2 > 60% and Tair > 40 °C abnormal combustion and knocking are observed.

This study investigates the production of green hydrogen for use in oil refining as specified in the draft of European union delegated act published in May 2022. The European union plans to set strict requirements of additionality and reporting regarding the criteria of renewable electricity used in hydrogen production. Alkaline electrolyzer proton exchange membrane electrolyzer and solid oxide electrolyzer are evaluated in various scenarios supplied by wind power: power purchase agreement-based scenarios and wind power investment-based scenarios. In power purchase agreement-based scenarios baseload and pay as produced power purchase agreements (with and without electricity storage) are assessed. According to results the use of 600 MW compressed air energy storage could reduce the dependency on the grid by 7% but increase the cost of green hydrogen significantly. Investment-based scenarios produce green hydrogen with a lower operation cost but higher break-even price compared to power purchase agreement-based scenarios. The cheapest green hydrogen can be achieved by alkaline electrolyzer with baseload power purchase agreement. Direct ownership of wind power is outside the operation of oil refining industry thus power purchase agreements contracting is more likely to realize.

Steel production is a carbon and energy intensive activity releasing 1.9 tons of CO2 and requiring 5.17 MWh of primary energy per ton produced on average globally resulting in 9% of all anthropogenic CO2 emissions. To achieve the goals of the Paris Agreement of limiting global temperature increase to below 1.5 °C compared to pre-industrial levels the structure of the global steel production must change fundamentally. There are several technological paths towards a lower carbon intensity for steelmaking which bring with them a paradigm shift decoupling CO2 emissions from crude steel production by transitioning from traditional methods of steel production using fossil coal and fossil methane to those based on low-cost renewable electricity and green hydrogen. However the energy system consequences of fully defossilised steelmaking has not yet been examined in detail. This research examines the energy system requirements a global defossilised power-to-steel industry using a GDP-based demand model for global steel demands which projects a growth in steel demand from 1.6 Gt in 2020 to 2.4 Gt in 2100. Three scenarios are developed to investigate the emissions trajectory energy demands and economics of a high penetration of direct hydrogen reduction and electrowinning in global steel production. Results indicate that the global steel industry will see green hydrogen demands grow significantly ranging from 2809 to 4371 TWhH2 by 2050. Under the studied conditions global steel production is projected to see reductions in final thermal energy demand of between 38.3% and 57.7% and increases in total electricity demand by factors between 15.1 and 13.3 by 2050 depending on the scenario. Furthermore CO2 emissions from steelmaking can be reduced to zero.

Appropriate climate change mitigation requires solutions for all actors of the energy system. The residential sector is a major part of the energy system and solutions for the implementation of a seasonal hydrogen storage system in residential houses has been increasingly discussed. A global analysis of prosumer systems including seasonal hydrogen storage with water electrolyser hydrogen compressor storage tank and a fuel cell studying the role of such a seasonal household storage in the upcoming decades is not available. This study aims to close this research gap via the improved LUT-PROSUME model which models a fully micro sector coupled residential photovoltaic prosumer system with linear optimisation for 145 regions globally. The modelling of the cost development of hydrogen storage components allows for the simulation of a residential system from 2020 until 2050 in 5-year steps in hourly resolution. The systems are cost-optimised for either on– or off-grid operation in eight scenarios including battery electric vehicles which can act as an additional vehicle-to-home electricity storage for the system. Results show that implementation of seasonal hydrogen systems only occurs in least cost solutions in high latitude countries when the system is forced to run in off-grid mode. In general a solar photovoltaic plus battery system including technologies that can cover the heat demand is the most economic choice and can even achieve lower cost than a full grid supply in off-grid operation for most regions until 2050. Additional parameters including the self-consumption ratio the demand cover ratio and the heat cover ratio can therefore not be improved by seasonal storage systems if economics is the main deciding factor for a respective system. Further research opportunities and possible limitations of the system are then identified.

Hydrogen as a suitable and clean energy carrier has been long considered a primary fuel or in combination with other conventional fuels such as gasoline and diesel. Since the density of hydrogen is very low in port fuel-injection configuration the engine’s volumetric efficiency reduces due to the replacement of hydrogen by intake air. Therefore hydrogen direct in-cylinder injection (injection after the intake valve closes) can be a suitable solution for hydrogen utilization in spark ignition (SI) engines. In this study the effects of hydrogen direct injection with different hydrogen energy shares (HES) on the performance and emissions characteristics of a gasoline port-injection SI engine are investigated based on reactive computational fluid dynamics. Three different injection timings of hydrogen together with five different HES are applied at low and full load on a hydrogen– gasoline dual-fuel SI engine. The results show that retarded hydrogen injection timing increases the concentration of hydrogen near the spark plug resulting in areas with higher average temperatures which led to NOX emission deterioration at −120 Crank angle degree After Top Dead Center (CAD aTDC) start of injection (SOI) compared to the other modes. At −120 CAD aTDC SOI for 50% HES the amount of NOX was 26% higher than −140 CAD aTDC SOI. In the meanwhile an advanced hydrogen injection timing formed a homogeneous mixture of hydrogen which decreased the HC and soot concentration so that −140 CAD aTDC SOI implied the lowest amount of HC and soot. Moreover with the increase in the amount of HES the concentrations of CO CO2 and soot were reduced. Having the HES by 50% at −140 CAD aTDC SOI the concentrations of particulate matter (PM) CO and CO2 were reduced by 96.3% 90% and 46% respectively. However due to more complete combustion and an elevated combustion average temperature the amount of NOX emission increased drastically.

The cost of storing and transporting hydrogen have been one of the main challenges for the realization of the hydrogen economy. Liquid organic hydrogen carriers (LOHC) are a promising novel solution to tackle these challenges. In this paper we compare the LOHC concept to compressed gas truck delivery and on-site production of hydrogen via water electrolysis. As a case study we consider transportation of by-product hydrogen from chlor-alkali and chlorate plants to a single industrial customer which was considered to have the greatest potential for the LOHC technology to enter the markets. The results show that the LOHC delivery chain could significantly improve the economics of long distance road transport. For economic feasibility the most critical parameters identified are the heat supply method for releasing hydrogen at the end-user site and the investment costs for LOHC reactors.

In FY-20 India’s steel production was 109 MT and it is the second-largest steel producer on the planet after China. India’s per capita consumption of steel was around 75 kg which has risen from 59 kg in FY-14. Despite the increase in consumption it is much lower than the average global consumption of 230 kg. The per capita consumption of steel is one of the strongest indicators of economic development across the nation. Thus India has an ambitious plan of increasing steel production to around 250 MT and per capita consumption to around 160 kg by the year 2030. Steel manufacturers in India can be classified based on production routes as (a) oxygen route (BF/BOF route) and (b) electric route (electric arc furnace and induction furnace). One of the major issues for manufacturers of both routes is the availability of raw materials such as iron ore direct reduced iron (DRI) and scrap. To achieve the level of 250 MT steel manufacturers have to focus on improving the current process and product scenario as well as on research and development activities. The challenge to stop global warming has forced the global steel industry to strongly cut its CO2 emissions. In the case of India this target will be extremely difficult by ruling in the production duplication planned by the year 2030. This work focuses on the recent developments of various processes and challenges associated with them. Possibilities and opportunities for improving the current processes such as top gas recycling increasing pulverized coal injection and hydrogenation as well as the implementation of new processes such as HIsarna and other CO2 -lean iron production technologies are discussed. In addition the eventual transition to hydrogen ironmaking and “green” electricity in smelting are considered. By fast-acting improvements in current facilities and brave investments in new carbon-lean technologies the CO2 emissions of the Indian steel industry can peak and turn downward toward carbon-neutral production.