Publications

Climatic changes are reaching alarming levels globally seriously impacting the environment. To address this environmental crisis and achieve carbon neutrality transitioning to hydrogen energy is crucial. Hydrogen is a clean energy source that produces no carbon emissions making it essential in the technological era for meeting energy needs while reducing environmental pollution. Abundant in nature as water and hydrocarbons hydrogen must be converted into a usable form for practical applications. Various techniques are employed to generate hydrogen from water with solar hydrogen production—using solar light to split water—standing out as a cost-effective and environmentally friendly approach. However the widespread adoption of hydrogen energy is challenged by transportation and storage issues as it requires compressed and liquefied gas storage tanks. Solid hydrogen storage offers a promising solution providing an effective and low-cost method for storing and releasing hydrogen. Solar hydrogen generation by water splitting is more efficient than other methods as it uses self-generated power. Similarly solid storage of hydrogen is also attractive in many ways including efficiency and cost-effectiveness. This can be achieved through chemical adsorption in materials such as hydrides and other forms. These methods seem to be costly initially but once the materials and methods are established they will become more attractive considering rising fuel prices depletion of fossil fuel resources and advancements in science and technology. Solid oxide fuel cells (SOFCs) are highly efficient for converting hydrogen into electrical energy producing clean electricity with no emissions. If proper materials and methods are established for solar hydrogen generation and solid hydrogen storage under ambient conditions solar light used for hydrogen generation and utilization via solid oxide fuel cells (SOFCs) will be an efficient safe and cost-effective technique. With the ongoing development in materials for solar hydrogen generation and solid storage techniques this method is expected to soon become more feasible and cost-effective. This review comprehensively consolidates research on solar hydrogen generation and solid hydrogen storage focusing on global standards such as 6.5 wt% gravimetric capacity at temperatures between −40 and 60 ◦C. It summarizes various materials used for efficient hydrogen generation through water splitting and solid storage and discusses current challenges in hydrogen generation and storage. This includes material selection and the structural and chemical modifications needed for optimal performance and potential applications.

The inherent intermittency of upstream solar and wind power can result in fluctuating electrolytic hydrogen production which is incompatible with the feedstock requirements of many downstream hydrogen storage and utilisation applications. Suitable backup power or storage (hydrogen or energy) strategies are thus needed in overall system design. This work conducts technoeconomic modelling to design electrolytic production systems featuring stable hydrogen output for various locations across Australia based on hourly weather data and determines the levelised cost of hydrogen (LCOH) emissions intensities and annual electrolyser usage factors. A stable truly green hydrogen supply is consistently achieved by imposing annual usage factor requirements on the system which forces the system modules (i.e. solar wind electrolyser and hydrogen storage) to be oversized in order to achieve the desired usage factor. Whilst the resultant system designs are however very location-specific a design that ensures a 100% usage factor costs approximately 22% more on average than a system design which is optimised for cost alone.

Meeting climate targets requires profound transformations in the energy system. Most energy uses should be electrified but where this is not feasible hydrogen can be part of the solution. However 98% of global hydrogen production involves greenhouse gas emissions with an average of 12 kg CO2e/kg H2. Therefore new hydrogen production pathways are needed in order to make hydrogen production compatible with climate targets. In this work we fill this gap by systematically comparing the energy and emissions intensity of 173 hydrogen production pathways suitable for the UK. Scenarios include onshore and offshore pathways and the use of repurposed infrastructure. Unlike fossil-fuel based pathways the results show that electrolytic hydrogen powered by fixed offshore wind could align with proposed emissions standards either onshore or offshore. However the embodied and fugitive emissions are important to consider for electrolytic pathways as they result in 10–50% of the total emissions intensity.

The production of green hydrogen requires significant water usage making the economic evaluation of different water sources crucial for optimizing the Levelized Cost of Hydrogen (LCOH). This study examines the economic impact of using seawater groundwater grid water industrial wastewater and rainwater for hydrogen production through PEM electrolysis considering the water abstraction transport treatment and storage costs across various plant sizes (1 MW 10 MW 20 MW 50 MW and 100 MW) were assessed and a sensitivity analysis on electricity prices was conducted. Findings reveal that while water-related costs are minimal.

This paper delves into the enhancement and optimization of on-grid renewable energy systems using a variety of renewable energy sources with a particular focus on large-scale applications designed to meet the energy demand of a certain load. As global concerns surrounding climate change continue to mount the urgency of replacing traditional fossil fuel-based power generation with cleaner more cost-effective and dependable alternatives becomes increasingly apparent. In this context a comprehensive investigation is conducted on grid connected hybrid energy system that combines photovoltaic wind and fuel cell technologies. The study employs three state-of-the-art optimization algorithms namely Walrus Optimization Algorithm (WaOA) Coati Optimization Algorithm (COA) and Osprey Optimization Algorithm (OOA) to determine the optimal system size and energy management strategies all aimed at minimizing the cost of energy (COE) for grid-based electricity. The results of the optimization process are compared with the results obtained from the utilization of the Particle swarm optimization (PSO) and Grey Wolf optimizer (GWO). The findings of this study underscore both the practical feasibility and the critical importance of adopting on-grid renewable energy systems to decrease the dependence on traditional energy sources within the grid. The proposed WaOA succeeded to reach the optimal solution of the optimal design process with a COE of 0.51758129611 $//kwh while keeping the loss of power supply probability (LPSP) the reliability index at 7.303681e-19. The practical recommendations and forwardlooking insights provided within this research hold the potential to foster sustainable development and effectively mitigate carbon emissions in the future.

Currently modern hydrogen technologies due to their low or zero emissions constitute one of the key elements of energy transformation and sustainable development. The growing interest in hydrogen is driven by the European climate policy aimed at limiting the use of fossil fuels for energy purposes. Although not all opinions regarding the technical and economic potential of hydrogen energy are positive many prepared forecasts and analyses show its prospective importance in several areas of the economy. The aim of this article is to provide a comprehensive review of modern materials current hydrogen technologies and strategies and show the opportunities problems and challenges Poland faces in the context of necessary energy transformation. The work describes the latest trends in the production transportation storage and use of hydrogen. The environmental social and economic aspects of the use of green hydrogen were discussed in addition to the challenges and expectations for the future in the field of hydrogen technologies. The main goals of the development of the hydrogen economy in Poland and the directions of actions necessary to achieve them were also presented. It was found that the existence of the EU CO2 emissions allowance trading system has a significant impact on the costs of hydrogen production. Furthermore the production of green hydrogen will become economically justified as the costs of energy obtained from renewable sources decrease and the costs of electrolysers decline. However the realisation of this vision depends on the progress of scientific research and technical innovations that will reduce the costs of hydrogen production. Government support mechanisms for the development of hydrogen infrastructure and technologies will also be of key importance.

This study develops a framework for designing hydrogen supply chains (HSC) in island territories using Mixed Integer Linear Programming (MILP) with a multi-period approach. The framework minimizes system costs greenhouse gas emissions and a risk-based index. Corsica is used as a case study with a Geographic Information System (GIS) identifying hydrogen demand regions and potential sites for production storage and distribution. The results provide an optimal HSC configuration for 2050 specifying the size location and technology while accounting for techno-economic factors. This work integrates the unique geographical characteristics of islands using a GIS-based approach incorporates technology readiness levels and utilizes renewable electricity from neighboring regions. The model proposes decentralized configurations that avoid hydrogen transport between grids achieving a levelized cost of hydrogen (LCOH) of €8.54/kg. This approach offers insight into future options and incentive mechanisms to support the development of hydrogen economies in isolated territories.

Hydrogen price significantly impacts its potential as a viable alternative in the sustainable energy transition. This study introduces a synergy-based Hydrogen Pricing Mechanism (HPM) within an integrated framework. The HPM leverages synergy between a Renewable-Penetrated Electric Power System (RP-EPS) and a Hydrogen Energy System (HES). Utilizing the Alternating Direction Method of Multipliers (ADMM) it facilitates data exchange quantifying integration levels and simplifying the complexities. The study assesses the HPM’s operational sensitivity across various scenarios of hydrogen generation transportation and storage. It also evaluates the benefits of synergy-based versus stand-alone HPMs. Findings indicate that the synergy-based HPM effectively integrates infrastructure and operational improvements from both EPS and HES leading to optimized hydrogen pricing.

If hydrogen fuel is available to support the transportation sector decarbonization its usage can be placed either directly onboard in a fuel cell vehicle or indirectly off-board by using a fuel cell power station to produce electricity to charge a battery electric vehicle. Therefore in this work the direct and indirect conversion scenarios of hydrogen to vehicle propulsion were investigated regarding energy efficiency. Thus in the first scenario hydrogen is the fuel for the onboard electricity production to propel a fuel cell vehicle while in the second hydrogen is the electricity source to charge the battery electric vehicle. When simulated for a drive cycle results have shown that the scenario with the onboard fuel cell consumed about 20% less hydrogen demonstrating higher energy efficiency in terms of driving range. However energy efficiency depends on the outside temperature when heat loss utilization is considered. For outside temperatures of − 5 ◦C or higher the system composed of the battery electric vehicle fueled with electricity from the off-board fuel cell was shown to be more energyefficient. For lower temperatures the system composed of the onboard fuel cell again presented higher total (heat + electricity) efficiency. Therefore the results provide valuable insights into how hydrogen fuel can be used for vehicle propulsion supporting the hydrogen economy development.

Hydrogen (2 ) has a big role to play in energy transition to achieve net-zero carbon emissions by 2050. For 2 to compete with other fuels in the energy market more research is required to mitigate key issues like greenhouse gas (GHG) emissions safety and end-use costs. For these reasons a software-supported technical overview of 2 production storage transportation and utilisation is introduced. Drawbacks and mitigation approaches for 2 technologies were highlighted. The recommended areas include solar thermal or renewable-powered plasma systems for feedstock preheating and oxy-hydrogen combustion to meet operating temperatures and heat duties due to losses; integration of electrolysis of 2 into hydrocarbon reforming methods to replace air separation unit (ASU); use of renewable power sources for electrical units and the introduction of thermoelectric units to maximise the overall efficiency. Furthermore a battolyser system for small-scale energy storage; new synthetic hydrides with lower absorption and desorption energy; controlled parameters and steam addition to the combustor/cylinder and combustors with fitted heat exchangers to reduce emissions and improve the overall efficiency are also required. This work also provided detailed information on any of these systems implementations based on location factors and established a roadmap for 2 production and utilisation. The proposed 2 production technologies are hybrid pyrolysis-electrolysis and integrated AD-MEC and DR systems using renewable bioelectrochemical and low-carbon energy systems. Production and utilisation of synthetic natural gas (NG) using renewablepowered electrolysis of 2 oxy-fuel and direct air capture (DAC) is another proposed 2 energy system for a sustainable 2 economy. By providing these factors and information researchers can work towards pilot development and further efficiency enhancement.