Publications

Hungary’s National Hydrogen Strategy (hereinafter referred to as: Strategy) is ambitious but provides a realistic vision of the future as it opens the way for the establishment of a hydrogen economy therefore contributing to the achievement of decarbonisation goals and providing an opportunity for Hungary to become an active participant of the European hydrogen sector. On the long term the Strategy focuses on “green” hydrogen but in addition to hydrogen based on electricity generated using renewable resources primarily solar energy Hungary does not ignore opportunities for hydrogen production based on carbon-free energy accessed either through a nuclear basis or from the network. Additionally in the short and medium term a rapid reduction in emissions and the establishment of a viable hydrogen market will also require low-carbon hydrogen.

Density functional theory (DFT) calculations have been performed to investigate the hydrogen dissociation and diffusion on Mg (0001) surface with Ni incorporating at various locations. The results show that Ni atom is preferentially located inside Mg matrix rather than in/over the topmost surface. Further calculations reveal that Ni atom locating in/over the topmost Mg (0001) surface exhibits excellent catalytic effect on hydrogen dissociation with an energy barrier of less than 0.05 eV. In these cases the rate-limiting step has been converted from hydrogen dissociation to surface diffusion. In contrast Ni doping inside Mg bulk not only does little help to hydrogen dissociation but also exhibits detrimental effect on hydrogen diffusion. Therefore it is crucial to stabilize the Ni atom on the surface or in the topmost layer of Mg (0001) surface to maintain its catalytic effect. For all the case of Ni-incorporated Mg (0001) surfaces the hydrogen atom prefers firstly immigrate along the surface and then penetrate into the bulk. It is expected that the theoretical findings in the present study could offer fundamental guidance to future designing on efficient Mg-based hydrogen storage materials.

This study presents an overview of the economic analysis and environmental impact of natural gas conversion technologies. Published articles related to economic analysis and environmental impact of natural gas conversion technologies were reviewed and discussed. The economic analysis revealed that the capital and the operating expenditure of each of the conversion process is strongly dependent on the sophistication of the technical designs. The emerging technologies are yet to be economically viable compared to the well-established steam reforming process. However appropriate design modifications could significantly reduce the operating expenditure and enhance the economic feasibility of the process. The environmental analysis revealed that emerging technologies such as carbon dioxide (CO2) reforming and the thermal decomposition of natural gas offer advantages of lower CO2 emissions and total environmental impact compared to the well-established steam reforming process. Appropriate design modifications such as steam reforming with carbon capture storage and utilization the use of an optimized catalyst in thermal decomposition and the use of solar concentrators for heating instead of fossil fuel were found to significantly reduced the CO2 emissions of the processes. There was a dearth of literature on the economic analysis and environmental impact of photocatalytic and biochemical conversion processes which calls for increased research attention that could facilitate a comparative analysis with the thermochemical processes.

Photocatalytic water splitting which directly converts solar energy into hydrogen is one of the most desirable solar-energy-conversion approaches. The ultimate target of photocatalysis is to explore efficient and stable photocatalysts for solar water splitting. Tantalum (oxy)nitride-based materials are a class of the most promising photocatalysts for solar water splitting because of their narrow bandgaps and sufficient band energy potentials for water splitting. Tantalum (oxy)nitride-based photocatalysts have experienced intensive exploration and encouraging progress has been achieved over the past years. However the solar-to-hydrogen (STH) conversion efficiency is still very far from its theoretical value. The question of how to better design these materials in order to further improve their water-splitting capability is of interest and importance. This review summarizes the development of tantalum (oxy)nitride-based photocatalysts for solar water spitting. Special interest is paid to important strategies for improving photocatalytic water-splitting efficiency. This paper also proposes future trends to explore in the research area of tantalum-based narrow bandgap photocatalysts for solar water splitting.

Combined cycle biomass calcium looping gasification is proposed for a hydrogen and electricity production (CLGCC–H) system. The process simulation Aspen Plus is used to conduct techno-economic analysis of the CLGCC–H system. The appropriate detailed models are set up for the proposed system. Furthermore a dual fluidized bed is optimized for hydrogen production at 700 °C and 12 bar. For comparison calcium looping gasification with the combined cycle for electricity (CLGCC) is selected with the same parameters. The system exergy and energy efficiency of CLGCC–H reached as high as 60.79% and 64.75% while the CLGCC system had 51.22% and 54.19%. The IRR and payback period of the CLGCC–H system based on economic data are calculated as 17.43% and 7.35 years respectively. However the CLGCC system has an IRR of 11.45% and a payback period of 9.99 years respectively. The results show that the calcium looping gasification-based hydrogen and electricity coproduction system has a promising market prospect in the near future.

Transformers are generally considered to be the costliest assets in a power network. The lifetime of a transformer is mainly attributable to the condition of its solid insulation which in turn is measured and described according to the degree of polymerization (DP) of the cellulose. Since the determination of the DP index is complex and time-consuming and requires the transformer to be taken out of service utilities prefer indirect and non-invasive methods of determining the DP based on the byproduct of cellulose aging. This paper analyzes solid insulation degradation by measuring the furan concentration recently introduced methanol and dissolved gases like carbon oxides and hydrogen in the insulating oil. A group of service-aged distribution transformers were selected for practical investigation based on oil samples and different kinds of tests. Based on the maintenance and planning strategy of the power utility and a weighted combination of measured chemical indicators a neural network was also developed to categorize the state of the transformer in certain classes. The method proved to be able to improve the diagnostic capability of chemical indicators thus providing power utilities with more reliable maintenance tools and avoiding catastrophic failure of transformers.

The APPG on Hydrogen has published its report urging the Government to deliver beyond its existing net zero commitments and set ambitious hydrogen targets in forthcoming strategies to reach net zero by 2050.

The All-Party Parliamentary Group (APPG) on Hydrogen’s report on the role of ‘Hydrogen in powering industry’ sets out 10 recommendations to support and accelerate the growth of the UK’s hydrogen sector and enable a sustainable energy transition.

• The Government must continue to expand beyond its existing commitments of 5GW production in the forthcoming Hydrogen Strategy.
• Any forthcoming Government and devolved policies must be complementary of the wider UK low-carbon commitments.
• Industrial clusters should be prioritised for hydrogen use and will be the key catalyst for driving forward the UK’s decarbonisation of industry.
• The Government must commit to incentivising hydrogen production within the UK as opposed to importing this.
• The Government must align hydrogen production pathways with nuclear technology to enhance hydrogen production.
• The Government must develop a UK wide hydrogen network to support the transport sector including a larger-scale implementation of hydrogen refuelling stations.
• Regulators must act quickly to update energy regulations and guidance to support hydrogen’s role in powering industry.
• For hydrogen to expand in the UK a technology neutral approach is required for all types of energy systems.
• Significant and long-term financial support is required for the development deployment and operation of hydrogen technologies.
• Ofgem must ensure the hydrogen market is subject to effective competition to drive down prices for consumers.

This paper designs the integrated charging station of PV and hydrogen storage based on the charging station. The energy storage system includes hydrogen energy storage for hydrogen production and the charging station can provide services for electric vehicles and hydrogen vehicles at the same time. To improve the independent energy supply capacity of the hybrid charging station and reduce the cost the components are reasonably configured. To minimize the configuration cost of the integrated charging station and the proportion of power purchase to the demand of the charging station the energy flow strategy of the integrated charging station is designed and the optimal configuration model of optical storage capacity is constructed. The NSGA-II algorithm optimizes the non-inferior Pareto solution set and a fuzzy comprehensive evaluation evaluates the optimal configuration.

In the last two years or so there has been increasing interest in hydrogen as an energy source in Australia and around the world. Notably this is not the first time that hydrogen has caught our collective interest. Most recently the 2000s saw a substantial investment in hydrogen research development and demonstration around the world. Prior to that the oil crises of the 1970s also stimulated significant investment in hydrogen and earlier still the literature on hydrogen was not lacking. And yet the hydrogen economy is still an idea only.<br/>So what if anything might be different this time?<br/>This is an important question that we all need to ask and for which the author can only give two potential answers. First our need to make dramatic reductions in greenhouse gas (GHG) emissions has become more pressing since these previous waves of interest. Second renewable energy is considerably more affordable now than it was before and it has consistently outperformed expectations in terms of cost reductions by even its strongest supporters.<br/>While this dramatic and ongoing reduction in the cost of renewables is very promising our need to achieve substantial GHG emission reductions is the crucial challenge. Moreover meeting this challenge needs to be achieved with as little adverse social and economic impact as possible.<br/>When considering what role hydrogen might play we should first think carefully about the massive scale and complexity of our global energy system and the typical prices of the major energy commodities. This provides insights into what opportunities hydrogen may have. Considering a temperate country with a small population like Australia we see that domestic natural gas and transport fuel markets are comparable to and even larger than the electricity market on an energy basis.

To increase the share of renewable zero-emission energy sources such as wind and solar power in our energy supply the problem of their intermittency needs to be addressed. One way to do so is by buffering excess renewable energy via the production of hydrogen which can be stored for later use after re-electrification. Such a clean renewable energy cycle based on hydrogen is commonly referred to as the hydrogen economy. This review deals with cluster model systems of the three main components of the hydrogen economy i.e. hydrogen generation hydrogen storage and hydrogen re-electrification and their basic physical principles. We then present examples of contemporary research on few atom clusters both in the gas phase and deposited to show that by studying these clusters as simplified models a mechanistic understanding of the underlying physical and chemical processes can be obtained. Such an understanding will inspire and enable the design of novel materials needed for advancing the hydrogen economy.