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The Australian transport sector is under increasing pressure to reduce carbon emissions whilst also managing a fuel supply chain that relies heavily on foreign import partners.



Transport in Australia equates to a significant proportion (approximately 18%) of the country’s total greenhouse gas emissions. Due to ongoing population growth these emissions have been steadily rising with the increase of cars on our roads and freight trucks in transit. Coupled with this the transport fuel supply chain is highly reliant on overseas partners – Australia currently imports 90% of its liquid fuel. These two challenges present an interesting dichotomy for the industry incentivising research and development into new technologies that can address one or both of these issues.



Hydrogen is one technology that has the potential to provide a reduction in greenhouse gas emissions as well as a more reliable domestic fuel supply. Hydrogen fuel cell electric vehicles (FCEVs) are an emerging zero-emission alternative for the transport sector which offer a variety of benefits.



Available from the Energy Ministers Website link here

Fischer-Tropsch synthesis (FTS) is an increasingly important approach for producing liquid fuels and chemicals via syngas—that is synthesis gas a mixture of carbon monoxide and hydrogen—generated from coal natural gas or biomass. In FTS dispersed transition metal nanoparticles are used to catalyze the reactions underlying the formation of carbon-carbon bonds. Catalytic activity and selectivity are strongly correlated with the electronic and geometric structure of the nanoparticles which depend on the particle size morphology and crystallographic phase of the nanoparticles. In this article we review recent works dealing with the aspects of bulk and surface sensitivity of the FTS reaction. Understanding the different catalytic behavior in more detail as a function of these parameters may guide the design of more active selective and stable FTS catalysts.

Proton exchange membrane (PEM) electrolysers (PEMEL) are key for converting and storing excess renewable energy. PEMEL water electrolysis offers benefits over alkaline water electrolysers including a large dynamic range high responsiveness and high current densities and pressures. High operating pressures are important because it contributes to reduce the costs and energy-use related to downstream mechanical compression. In this work the performance of a high-pressure PEMEL system has been characterized up to 180 bar. The electrolyser stack has been characterized with respect to electrochemical performance net H2 production rate and water crossover and the operability and performance of the thermal- and gas management systems of the test bench has been assessed. The tests show that the voltage increase upon pressurization from 5 to 30 bar is 30 % smaller than expected but further pressurization reduces performance. The study confirms that highpressure PEMEL has higher energy consumption than state-of-the-art electrolyser systems with mechanical compressors. However there can be a business case for high-pressure PEMEL if the trade-off between stack efficiency and system efficiency is balanced.

The deployment of low-emission alternative fuels is crucial to decarbonise the transport sector. A number of alternatives like hydrogen or dimethyl ether/methanol synthesised using CO2 as feedstock for fuel production (hereafter refer to “CO2-based fuels”) have been proposed to combat climate change. However the decarbonisation potential of CO2-based fuels is under debate because CO2 is re-emitted to the atmosphere when the fuel is combusted; and the majority of hydrogen still relies on fossil resources which makes its prospects of being a low-carbon fuel dependent on its manufacturing process. First this paper investigates the relative economic and environmental performance of hydrogen (produced from conventional steam methane reforming and produced via electrolysis using renewable energy) and CO2- based fuels (dimethyl ether and methanol) considering the full carbon cycle. The results reveal that hydrogen produced from steam methane reforming is the most economical option and that hydrogen produced via electrolysis using renewables has the best environmental profile. Whereas the idea of CO2-based fuels has recently gained much interest it has for the foreseeable future rather limited practical relevance since there is no favourable combination of cost and environmental performance. This will only change in the long run and requires that CO2 is of non-fossil origin i.e. from biomass combustion or captured from air. Second this paper address unresolved methodological issues in the assessment of CO2-based fuels such as the possible allocation of emissions to the different sectors involved. The outcomes indicate that implementing different allocation approaches substantially influences the carbon footprint of CO2-based fuels. To avoid allocation issues expanding the boundaries including the entire system and is therefore recommended.

Hydrogen has seen unprecedented development in the year 2020. From innovative niche technology it is fast becoming a systemic element in the European Union’s (EU) efforts to transition to a climate-neutral society in 2050. It will become a crucial energy vector and the other leg of the energy transition – alongside renewable electricity – by replacing coal oil and gas across different segments of the economy. The rapid development of hydrogen is important for meeting the EU’s climate objectives and preserving and enhancing the EU’s industrial and economic competitiveness securing jobs and value creation in this high-tech sector.

Europe is currently leading in hydrogen technology and European companies and knowledge institutions can be instrumental in advancing technological developments and industrial scale-up. It is imperative that Europe maintains this leadership position and seizes the current momentum for hydrogen technologies. The EU is well placed to become the birthplace of a global hydrogen economy denominated in Euro currency.

It is time that hydrogen moves from an afterthought to a central pillar of the energy system. The “Fit for 55 Package” presents a unique opportunity to begin putting into place a concrete and fit for purpose framework for the development of a clean hydrogen economy. In this paper you will find Hydrogen Europe’s recommendations on how hydrogen can:

• Unleash the potential of renewables.
• Bring “efficiency” to the energy “system” of the future.
• Enable a carbon-neutral transport system.

The Oxford Institute for Energy Studies held a Workshop on “The Future of Gas Networks” to examine decarbonisation plans and the impact of the potential growth in the use of renewable and decarbonised gases in Europe. Participants included representatives from nine European gas network companies (both transmission and distribution) technical experts in decarbonisation regulators government officials and academics. This document summarises the seven key issues for debate arising from the Workshop discussions:

• The major gas networks recognise the need to prepare for and facilitate decarbonisation.
• The route to decarbonisation can take many forms though hydrogen is likely to feature in most networks. In larger countries solutions are likely to be regional rather than national.
• There are a number of pilot projects and targets/aspirations for 2050 – there is less clarity on how the targets will be achieved or on who will lead.
• Regulation is a key issue. In most countries existing regulatory objectives may need changing in order to align with government decarbonisation aspirations and the achievement of targets.
• There is a lack of consensus on whether and how market models might need to adapt.
• Detailed stakeholder analysis – and in particular customer attitudes – will be required.
• There are a range of important technical issues including standardisation data quality and transparency verification and certification to be considered.

Link to document on Oxford Institute for Energy Studies website

Due to the low density of hydrogen gas under ambient temperature and atmospheric pressure conditions the high-pressure gaseous hydrogen storage method is widely employed. With high-pressure characteristics of hydrogen storage rigorous safety precautions are required such as filling of compressed gas in a hydrogen tank to achieve reliable operational solutions. Especially for the large-sized tanks (above 150 L) safety operation of hydrogen storage should be considered. In the present study the compressed hydrogen gas behavior in a large hydrogen tank of 175 L is investigated for its filling. To validate the numerical approach used in this study numerical models for the adaptation of the gas and turbulence models are examined. Numerical parametric studies on hydrogen filling for the large hydrogen tank of 175 L are conducted to estimate the hydrogen gas behavior in the hydrogen tank under various conditions of state of charge of pressure and ambient temperature. From the parametric studies the relationship between the initial SOC pressure condition and the maximum temperature rise of hydrogen gas was shown. That is the maximum temperature rise increases as the ambient temperature decreases and the rise increases as the SOC decreases.

The computational thermodynamic analysis of a samarium oxide-based two-step solar thermochemical water splitting cycle is reported. The analysis is performed using HSC chemistry software and databases. The first (solar-based) step drives the thermal reduction of Sm2O3 into Sm and O2. The second (non-solar) step corresponds to the production of H2 via a water splitting reaction and the oxidation of Sm to Sm2O3. The equilibrium thermodynamic compositions related to the thermal reduction and water splitting steps are determined. The effect of oxygen partial pressure in the inert flushing gas on the thermal reduction temperature (TH) is examined. An analysis based on the second law of thermodynamics is performed to determine the cycle efficiency (ηcycle) and solar-to-fuel energy conversion efficiency (ηsolar´to´fuel) attainable with and without heat recuperation. The results indicate that ηcycle and ηsolar´to´fuel both increase with decreasing TH due to the reduction in oxygen partial pressure in the inert flushing gas. Furthermore the recuperation of heat for the operation of the cycle significantly improves the solar reactor efficiency. For instance in the case where TH = 2280 K ηcycle = 24.4% and ηsolar´to´fuel = 29.5% (without heat recuperation) while ηcycle = 31.3% and ηsolar´to´fuel = 37.8% (with 40% heat recuperation).

To limit the global temperature change to no more than 2 ◦C by reducing global emissions the European Union (EU) set up a goal of a 20% improvement on energy efficiency a 20% cut of greenhouse gas emissions and a 20% share of energy from renewable sources by 2020 (10% share of renewable energy (RE) specifically in the transport sector). By 2030 the goal is a 27% improvement in energy efficiency a 40% cut of greenhouse gas emissions and a 27% share of RE. However the integration of RE in energy system faces multiple challenges. The geographical distribution of energy supply changes significantly the availability of the primary energy source (wind solar water) and is the determining factor rather than where the consumers are. This leads to an increasing demand to match supply and demand for power. Especially intermittent RE like wind and solar power face the issue of energy production unrelated to demand (issue of excess energy production beyond demand and/or grid capacity) and forecast errors leading to an increasing demand for grid services like balancing power. Megawatt electrolyzer units (beyond 3 MW) can provide a technical solution to convert large amounts of excess electricity into hydrogen for industrial applications substitute for natural gas or the decarbonization of the mobility sector. The demonstration of successful MW electrolyzer operation providing grid services under dynamic conditions as request by the grid can broaden the opportunities of new business models that demonstrate the profitability of an electrolyzer in these market conditions. The aim of this work is the demonstration of a technical solution utilizing Pressurized Alkaline Electrolyzer (PAE) technology for providing grid balancing services and harvesting Renewable Energy Sources (RES) under realistic circumstances. In order to identify any differences between local market and grid requirements the work focused on a demonstration site located in Austria deemed as a viable business case for the operation of a largescale electrolyzer. The site is adapted to specific local conditions commonly found throughout Europe. To achieve this this study uses a market-based solution that aims at providing value-adding services and cash inflows stemming from the grid balancing services it provides. Moreover the work assesses the viability of various business cases by analyzing (qualitatively and quantitatively) additional business models (in terms of business opportunities/energy source potential grid service provision and hydrogen demand) and analyzing the value and size of the markets developing recommendations for relevant stakeholder to decrease market barriers.

Owing to their extremely high energy density single-bonded polymeric nitrogen and atomic metallic hydrogen are generally regarded as the ultimate energetic materials. Although their syntheses normally require ultrahigh pressures of several hundred gigapascals (GPa) which prohibit direct materials application research on their stability metastability and fundamental properties are valuable for seeking extreme energetic materials through alternative synthetic routes. Various crystalline and amorphous polymeric nitrogens have been discovered between 100 and 200 GPa. Metastability at ambient conditions has been demonstrated for some of these phases. Cubic-gauche and black-phosphorus polymorphs of single-bonded nitrogen are two particularly interesting phases. Their large hystereses warrant further application-inspired basic research of nitrogen. In contrast although metallic hydrogen contains the highest-estimated energy density its picosecond lifetime and picogram quantity make its practical material application impossible at present. “Metallic hydrogen” remains a curiosity-driven basic research pursuit focusing on the pressure-induced evolution of the molecular hydrogen crystal and its electronic band structure from a low-density insulator with a very wide electronic band gap to a semiconductor with a narrow gap to a dense molecular metal and atomic metal and eventually to a previously unknown exotic state of matter. This great experimental challenge is driving relentless advancement in ultrahigh-pressure science and technology.