Large-scale Storage Research Articles

Ammonia Driven Reversible Solid Oxide Cell As Large-Scale Grid Energy Storage System

The global agreement on the reduction of greenhouses entails increased use of intermittent renewable energy sources such as wind and solar. In this contest, there is a huge need for efficient and cost-effective energy storage systems. Currently, different types of grid energy storage systems are under operation worldwide. However, few of them have the capacity of storing several MWhs of electricity. Large-scale energy storage systems will play a vital role in grid stabilization by reducing imbalances between energy production and demand. Solid oxide cells (SOC) are promising and efficient technologies operating both on electrolyzer and fuel cell modes applicable for energy storage and production. The efficiency of SOC can be further increase by utilization of excess high temperature steam from other processes like ammonia synthesis when it is operating as electrolyzer. In this way, part of the energy needed for electrlozer is covered and less input energy is required, which leads to higher efficiency. This is the main reason behind combining solid oxide cells with the ammonia synthesis process. In the present work, we propose a large-scale electricity storage system operating with reversible solid oxide cells (RSOC) to store electricity as synthetic ammonia. Ammonia can be easily produced, when RSOC operates as an electrolyzer, and stored in the liquid form during off-peak demand. During the peak demand, stored ammonia can be fed into the RSOC, when RSOC operates as a fuel cell, to produce green electricity. Besides the RSOC, the proposed system mainly consists of an air separation unit (ASU) and a Haber-Bosch loop (HBL). Besides large-scale storing of grid electricity, such a system can create an efficient link between electricity and ammonia markets. The system performance is evaluated at a component level thermodynamic analysis showing that a round-trip storage efficiency higher than 50% is achievable.

Lorentz-Force-Mediated Zn Electrodeposition and Br- Ion Convection for Improved Performance in Aqueous Zn-Br2 Static Batteries

Redox flow batteries are one of the prominent electrochemical energy storage devices with large-scale storage and high energy density.1 The highly reversible Zn/Zn2+ (-0.76 V vs. RHE) and Br-/Br2 (1.08 V vs. RHE) redox couple have been employed in Zn-Br2 flow batteries (1.84 V vs. RHE). However, the dendritic growth of Zn electrodeposits during the repetitive discharge process triggers an internal short-circuit between the anode and the cathode.1 Besides this, cross-diffusion of the highly soluble Br- (Br3 -) ion causes a severe self-discharge of the system and reduced cycle life.2 Additives and ion-selective membranes have been employed to mitigate these challenges for improved cycle life and coulombic efficiency in Zn-Br2 batteries.3 Here, we fabricate an aqueous Zn-Br2 static battery with internally contained and moderate magnetic fields, (~ 30, 40, 50 and 60 mT) at the anode and cathode by incorporating 1 mm thick Nd permanent magnets. A solid complex of tetrapropylammonium tribromide was supported on activated carbon and employed as the positive electrode. Introducing a magnetic field can generate the Lorentz force (acting on Br- and Zn2+ ions), and create a controllable magnetohydrodynamic mass transport during the charge-discharge processes. Among the various magnetic fields, ~50 mT resulted in the highest coulombic efficiency (99 % for 100 cycles) and suppressed Zn dendritic growth. To rationalize the effect of magnetic fields on the efficiency and cycle life, Raman analysis, X-ray diffraction, scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry (for the calculation of diffusion coefficient of Br- ion) are performed on the positive and negative electrodes of Zn-Br2 battery.

Novel Anion-Exchange Blend Membranes Comprised of a Commercially Available & Water-Soluble Ionomer for All-Vanadium Redox Flow Batteries

The All-Vanadium Redox Flow Battery is a promising technology for solving the problem of cost-efficient and safe large-scale storage of renewable energies [1]. One key component of the batteries, which alters the performance and long-term stability of those systems, is the membrane. For this purpose, Nafion based membranes are often used. However, these membranes are high in cost and show a significant capacity fading and reduction of coulombic efficiency mainly due to crossover of vanadium species [2]. One way around this is to use commercially available, low-cost materials with positively charged ammonium groups, which can effectively repel positively charged vanadium species due to the Donnan exclusion effect [3, 4].In this work we present novel anion-exchange blend membranes comprised of a commercially available and water-soluble ionomer and a PBI blend matrix, which can be used in All-Vanadium Redox Flow batteries. For this approach the water-soluble ionomer was modified to achieve solubility in organic solvents and miscibility with the matrix polymer. The resulting membranes show good mechanical properties even at high IECs and can be modified in a wide range of properties by adjusting the amounts of ionomer and matrix polymer and/or by the addition of crosslinking agents.The above-mentioned membranes were characterised ex-situ by using EIS, NMR spectroscopy, IR spectroscopy, DMA, TGA, tensile tests and permeability tests. In addition, first promising in-situ characterisations were performed in a VRFB single-cell test station.Literature[1] Fan, X; Liu, B; Liu, J; Ding, J; Han, X; Deng, Y; Lv, X; Xie, Y; Chen, B; Hu, W; Zhong, C.: Battery Technologies for Grid-Level Large-Scale Electrical Energy Storage. Trans. Tianjin Univ. 2020, 92 – 103.[2] Düerkop, D; Widdecke, H; Schilde, C; Kunz, U; Schmiemann, A.: Polymer Membranes for All-Vanadium Redox Flow Batteries: A Review. Membranes 2021.[3] Xi, J; Wu, Z; Teng, X; Zhao, Y; Chen, L; Qiu, X.: Self-assembled polyelectrolyte multilayer modified Nafion membrane with suppressed vanadium ion crossover for vanadium redox flow batteries. J. Mater. Chem. 2008, 1232.[4] Mohammadi, T; Kazacos, M.: Modification of anion-exchange membranes for vanadium redox flow battery applications. Journal of Power Sources 1996, 179 – 186.

(Digital Presentation) Hydrogen Peroxide Electrolyzer and Reversible Hydrogen Peroxide Cycle Cell for Renewable Energy Storage

The rapid increase of intermittent renewable energy such as wind and solar powers requires large-scale, efficient, economic, and zero-emission systems for energy storage.1,2 Energy storage based on the H2-water cycle realized by water electrolyzers and fuel cells has been proposed for large-scale energy storage and grid-balancing.1,3,4 However, the energy efficiency of H2-water cycle is restricted by the sluggish kinetics of the electrochemical oxygen evolution and oxygen reduction reactions in water electrolyzers and fuel cells, respectively.5-7 In this presentation, we will discuss the concept of distributed generation and energy storage systems based on the highly efficient electrochemical cycle of hydrogen peroxide (H2O2).8 In this concept, H2O2 can be electrolyzed to H2 and O2 to store the energy in the short term and then be regenerated via the two-electron oxygen reduction reaction in a fuel cell-type device to generate power. We will also discuss the techno-economical analysis of large-scale, long-term hydrogen and energy storage using H2O2 as the storage media.As a proof of concept, we will summarize our work on proton exchange membrane hydrogen peroxide electrolyzer (PEM-HPEL), which employs platinum group metal-free (PGM-free) catalysts for hydrogen peroxide oxidation reaction at the anode.8 The prototypes of PEM HPEL showed low onset cell voltage of ca. 0.7 to 0.8 V with 0 to 0.1 V overpotentials and a high voltage efficiency of over 90%. We will also present our work on unitized regenerative hydrogen peroxide cycle cells (UR-HPCC) based on PGM-free bifunctional oxygen electrode catalyst.9 This UR-HPCC operates in either HPEL mode or fuel cell mode for energy storage and power generation, with an ultralow overpotential and an extremely high round-trip voltage efficiency of over 90%. The minimal system cost, low power consumption, and high energy efficiency render the above H2O2 electrochemical cycle systems highly attractive for short- and long-term energy/hydrogen storage.

An Exploration of Nitrogen-Rich Fused Heteroaromatic Quinones for Redox Flow Battery Applications

The growing need to transition from fossil fuels to renewable energy sources will require innovative development of grid-level electrochemical energy storage.1 Suitable grid-level storage must provide a high cycle number durability, long calendar life, high efficiency, low cost and fast response time.2–4 Redox flow batteries (RFBs) are one potential solution boasting a decoupled power and capacity scaling.1,4,5 However, the low energy density1,6,7 and high capital costs6,7 of current systems preclude wide-scale deployment of this technology. Increasing energy density can be achieved in various ways: expanding the voltage window or by minimising the mass and/or volume per electron transferred.8 These offer potential strategies for electrolyte exploration but the challenge is to minimise the cost while providing as much electrical energy storage as possible.Current electrolyte systems for RFBs rely on a variety of metal-based systems (vanadium,9 iron,10 chromium10)1,11 and a range of organic molecules (nitroxide radicals,12 phenazines,12–14 viologens,15 and quinones16–18).4,5 Quinones offer fast kinetics, high tunability and low cost.5 Of these, higher order quinones offer increased chemical and electrochemical stability.5 In this work, an exploration of nitrogen-rich fused heteroaromatic quinones was carried out to investigate new avenues for electrolyte development. The electrolytes were screened using electrochemical techniques and the most promising candidate was tested in a lab-scale flow battery as an anolyte under aqueous conditions. Sitting at -0.7 V(SHE), a capacity fade rate of 0.004%.cycle-1 was found in symmetric cycling. In situ UV-Vis, NMR19,20 and EPR19 spectroscopy were used to investigate the electrochemical stability and nature of the charged species involved during operation, complemented by density functional theory modelling. These studies indicate that fused systems of this type may be promising candidates for aqueous RFBs. Alotto, P., Guarnieri, M. & Moro, F. Redox flow batteries for the storage of renewable energy: A review. Renew. Sustain. Energy Rev. 29, 325–335 (2014).Weber, A. Z. et al. Redox flow batteries: A review. J. Appl. Electrochem. 41, 1137–1164 (2011).Gyuk, I. et al. Grid Energy Storage. (2013).Cao, J., Tian, J., Xu, J. & Wang, Y. Organic Flow Batteries: Recent Progress and Perspectives. Energy and Fuels 34, 13384–13411 (2020).Ding, Y., Zhang, C., Zhang, L., Zhou, Y. & Yu, G. Molecular engineering of organic electroactive materials for redox flow batteries. Chem. Soc. Rev. 47, 69–103 (2018).Potash, R. A., McKone, J. R., Conte, S. & Abruña, H. D. On the Benefits of a Symmetric Redox Flow Battery. J. Electrochem. Soc. 163, A338–A344 (2016).Wang, W. et al. Recent progress in redox flow battery research and development. Adv. Funct. Mater. 23, 970–986 (2013).Armand, M. & Tarascon, J. M. Building better batteries. Nature 451, 652–657 (2008).Ulaganathan, M. et al. Recent Advancements in All-Vanadium Redox Flow Batteries. Adv. Mater. Interfaces 3, (2016).Sun, C. & Zhang, H. A review of the development of the first‐generation redox flow battery : iron chromium system. ChemSusChem (2021). doi:10.1002/CSSC.202101798Noack, J., Roznyatovskaya, N., Herr, T. & Fischer, P. The Chemistry of Redox-Flow Batteries. Angew. Chemie - Int. Ed. 54, 9776–9809 (2015).Winsberg, J. et al. Aqueous 2,2,6,6-Tetramethylpiperidine-N-oxyl Catholytes for a High-Capacity and High Current Density Oxygen-Insensitive Hybrid-Flow Battery. ACS Energy Lett. 2, 411–416 (2017).Kwon, G. et al. Multi-redox Molecule for High-Energy Redox Flow Batteries. Joule 2, 1771–1782 (2018).Romadina, E. I., Komarov, D. S., Stevenson, K. J. & Troshin, P. A. New phenazine based anolyte material for high voltage organic redox flow batteries. Chem. Commun. 57, 2986–2989 (2021).Hu, S. et al. Phenylene-Bridged Bispyridinium with High Capacity and Stability for Aqueous Flow Batteries. Adv. Mater. 33, 2005839 (2021).Suo, L. et al. Advanced High-Voltage Aqueous Lithium-Ion Battery Enabled by “Water-in-Bisalt” Electrolyte. Angew. Chemie - Int. Ed. 55, 7136–7141 (2016).Shimizu, A. et al. Liquid Quinones for Solvent-Free Redox Flow Batteries. Adv. Mater. 29, 1606592 (2017).Yang, Z. et al. Alkaline Benzoquinone Aqueous Flow Battery for Large-Scale Storage of Electrical Energy. Adv. Energy Mater. 8, 1702056 (2018).Zhao, E. W. et al. Coupled in Situ NMR and EPR Studies Reveal the Electron Transfer Rate and Electrolyte Decomposition in Redox Flow Batteries. J. Am. Chem. Soc. 143, 1885–1895 (2021).Zhao, E. W. et al. In situ NMR metrology reveals reaction mechanisms in redox flow batteries. Nature 579, 224–228 (2020). Figure 1

GIS-based solar and wind resource assessment and least-cost 100 % renewable electricity modelling for Bolivia

Rapid cost reductions of solar photovoltaics and wind offer a pathway to deep decarbonization of energy at low cost. Off-river pumped hydro energy storage provides mature, cheap and very large-scale storage that helps to balance variable generation and demand while avoiding environmental and social impacts. Many developing countries, especially those in the sunbelt, have the opportunity to adopt this pathway and bypass additional fossil fuel capacities while developing their economies. This study investigates the feasibility of such pathway for Bolivia, a country that relies heavily on fossil gas for both domestic energy consumption and export income. The current reliance on fossil gas, however, is untenable in the long-term due to the worldwide transition to low carbon energy, and the potential growth in per capita energy demand. Instead, a GIS-based resource assessment presented in this study identifies massive low-cost solar photovoltaic, wind and pumped hydro potential that are far more than needed to supply and balance the future electricity demand in Bolivia. A 10-year hourly energy balance model is presented of a future Bolivian electricity system with 100 % renewable electricity supplied by solar, wind and hydroelectricity, and balanced by off-river pumped hydro and high voltage transmission. It is found that the levelized cost of electricity is in the range $44–53/MWh across all scenarios, which is lower than the cost of electricity from new hydroelectricity or gas plants. Importantly, the costs modelled in this study are upper bounds because only technologies that are already deployed in large quantities worldwide are included.

Ultrafast and Long-Cycle Stable Aluminum Polyphenylene Batteries.

Rechargeable aluminum-ion batteries (RAIBs) are highly sought after due to the extremely high resource reserves and theoretical capacity (2980 mA h/g) of metal aluminum. However, the lack of ideal cathode materials restricts its practical advancement. Here, we report a conductive polymer, polyphenylene, which is produced by the polymerization of molecular benzene as a cathode material for RAIBs with an excellent electrochemical performance. In electrochemical redox, polyphenylene is oxidized and loses electrons to form radical cations and intercalates with [AlCl4]- anion to achieve electrical neutrality and realize electrochemical energy storage. The stable structure of polyphenylene makes its discharge specific capacity reach 92 mA h/g at 100 mA/g; the discharge plateau is about 1.4 V and exhibits an excellent rate performance and long cycle stability. Under the super high current density of 10 A/g (∼85 C), the charging can be completed in 25 s, and the capacities have almost no decay after 30,000 cycles. Aluminum polyphenylene batteries have the potential to be used as low-cost, easy-to-process, lightweight, and high-capacity superfast rechargeable batteries for large-scale stationary power storage.

Real-Time and Rapid Food Quality Monitoring Using Smart Sensory Films with Image Analysis and Machine Learning

Detecting and reporting the quality of packaged food to the consumer in real-time can reduce the consumption of poor-quality food products. Current food quality detection and reporting technologies of perishable foods are usually expensive, complicated, and take a significantly long time to convey results. Herein, a real-time, simple, and user-friendly food freshness detection prototype was developed by combining a glycerol-based sensory film with unique visual color analysis and the k-nearest neighbors algorithm (KNN). We established the quantitative relationship between the pH, organic acid level, digital color variance, and food storage time. By measuring the color variations of sensor films as a function of food storage time, we demonstrate a technology to record the quantitative “RGB” values of sensory films to represent real-time and precise pH changes of the food sample and trace the real-time food spoilage degree (e.g., pork loin spoilage). Next, a quick-response (QR) reader with a center sensor film was designed to eliminate the environmental effects on the color variation in real time Furthermore, the KNN was implemented to classify food quality by training data from different sources. This study provides a technology well suited for large-scale food storage applications by combining a smart sensor film with a QR code design followed by image analysis and KNN. This real-time and rapid food quality monitoring technology will ultimately lead to a reduction in food waste and loss (FLW).

Advanced anion-selective membranes with pendant quaternary ammonium for neutral aqueous supporting redox flow battery

Neutral aqueous organic redox flow battery (NAORFB) stands out as one of the most prospective mass energy storage options. The main limitations of large-scale storage regarding the NAORFB lie in the low Na+/Cl− conductivity of membrane in pH7 systems, which leads to a lower voltage efficiency. Herein, quaternary ammonium functionalized fluorinated poly (arylene ether) (QAFPAE-x) anion exchange membrane with hydrophilic and hydrophobic blocks was designed successfully. The results demonstrated that the grafting of quaternary ammonium and fluorine-containing block enables QAFPAE-x membrane low swelling, high Cl− conductivity, and promising chemical stability characteristics. The voltage efficiency of QAFPAE-100 membrane (93.8%–60.7%) is much higher than the AMVN membrane (88.4%–37.8%) at 20–160 mA cm−2. Furthermore, the NAORFB with the QAFPAE-100 membrane steadily runs at 60 mA cm−2 over 1500 cycles. Therefore, the ionic highway induced excellent performance of QAFPAE-100 membrane to render this material a promising candidate for practical NAORFB applications.

Ldasip: A Lightweight Dynamic Audit Approach for Sensitive Information Protection in Cloud Storage

How to audit the integrity of data stored on the cloud with incomplete trust is an important problem that restricts the development of cloud storage. Although there are several data integrity audit schemes in cloud storage, the increased need to protect sensitive information and support large-scale data storage and dynamic update will result in a significant increase in audit cost, which seriously affects the efficiency of existing cloud audit systems. To solve this problem, we propose Ldasip, a lightweight dynamic auditing method that supports sensitive information protection in cloud storage. Exploiting identity-based data integrity audit, a data masking technology is introduced into to protect user’s sensitive information. At the same time, an improved multibranch tree structure is proposed to realize dynamic audit and reduce communication overhead in the verification process. Theoretical analysis and comprehensive experiments have been conducted, which demonstrate the effectiveness of Ldasip. The results show that Ldasip can ensure the correctness of the audit, protect the sensitive information in the user's stored content, and support the dynamic update of data with less audit time and communication overhead.

Promising material for large-scale H2 storage and efficient H2-CO2 separation

Hydrogen is a clean energy source which can replace fossil fuels in a hydrogen economy, thereby drastically mitigating climate change. However, hydrogen storage – due to the high volatility of hydrogen – and H2-CO2 separation (a key requirement in the industrial hydrogen production) are currently the main obstacles in implementing such a hydrogen economy.We thus developed an advanced material which is highly efficient in terms of H2 storage, but also H2 separation fom CO2 streams. We thus modified sub-bituminous coal by incorporating different concentrations of nano-sized CaO nanofluid into the coal. The raw and modified coals (sub-bituminous-1, sub-bituminous-2 and sub-bituminous-3) were characterized and tested for their hydrogen storage capacity and H2-CO2 separation efficiency.Indeed, sub-bituminous-2 reached a very high H2 adsorption capacity (up to 0.866 mol.kg−1) and clearly can therefore store large quantities of H2. In addition, sub-bituminous-3 demonstrated excellent H2-CO2 separation efficiency (CO2-H2 adsorption selectivities of up to 4.1 were measured). This work therefore illustrates new highly cost-effective and technically efficient materials for H2 storage and H2 production, thus aiding in the industrial-scale implementation of a hydrogen economy.

Hydrogen storage in Majiagou carbonate reservoir in China: Geochemical modelling on carbonate dissolution and hydrogen loss

Underground hydrogen storage (UHS) appears to be promising means for large-scale hydrogen storage. Carbonate reservoirs can play an important role in hydrogen storage in particular in Western China and Middle East region. However, little work has been done to address the potential risks and uncertainties associated with carbonate dissolution and hydrogen loss as a result of hydrogen-brine-carbonate geochemical reactions. We thus performed geochemical modelling to assess the potential of UHS in Majiagou carbonate formation, China. Kinetic models of the dissolution/precipitation of calcite, dolomite and quartz were developed to characterize hydrogen loss, mineral dissolution and water chemistry variations up to 500 years.The results show that the percentage of hydrogen loss due to fluid-rock interactions is only 6.6% for the first year, but could increase to 81.1% at the end of 500 years during UHS in Majiagou formation, indicating that carbonate reservoirs is suitable for hydrogen seasonal storage but may not be a good candidate for long-term storage. Meanwhile, totally 0.0646% of calcite would dissolve into formation brine over 500 years, bringing potential risks on caprock and wellbore stability and formation integrity. Besides, we observed a considerable amount of methane generated along with H2-brine-carbonate interactions. Our works provide a framework to assess the hydrogen storage capacity of carbonate reservoirs using geochemical modelling, and can be also applied to other types of storage deposits.

The influence of frequency containment reserve on the efficiency of a hybrid stationary large-scale storage system

Large-scale battery storage systems are predestined for balancing the fluctuating feed-in from renewable energies and supporting the electricity grid due to their high efficiency. As a result, large-scale storage has gained importance in the market for frequency support reserve (FCR). While the first LSS projects had to be planned without operational experience a couple of years ago, new LSS can benefit from the evaluation of measured field data. Especially the real-word efficiencies are key information for electricity procuring costs and arbitrage trading. To contribute filling this information gap, this paper investigates the efficiency of the hybrid LSS, its transformers, its inverters, the individual battery technologies (two types of lead-acid and three types of lithium-ion batteries) and the influence of FCR provision on efficiency. High-resolution field measurements of the hybrid 6 MW/7.5 MWh battery storage system “M5BAT” at the FCR market over several years serve as the basis. The data-based efficiency analysis reveals a high round-trip efficiency of 72.8% (with self-consumption: 66.2%) for the LSS in operation. In this context, the lithium-ion batteries have a higher round-trip efficiency of 97.4% than the lead-acid batteries with 85%. Low load on the transformers and the inverters leads to an average power-weighted power efficiency of less than 95%. The results presented can be used to model LSS and its various system components and battery technologies in order to further analyse the participation in chosen energy markets.

The influence of frequency containment reserve on the cycles of a hybrid stationary large-scale storage system

Europe's aim of climate neutrality by 2050 places higher demands on the electricity grid due to the expansion of renewable energies with fluctuating feed-in. With their high flexibility and reaction speed, large-scale storage systems (LSS) are predestined to compensate the fluctuating feed-in from renewable energies and to support the electricity grid. For this reason, LSS are gaining importance on the market for frequency containment reserve (FCR) as well as in research. The majority of publications investigating the interaction between storage and FCR are based on simulations and, field measurements are rare. This paper presents the analyses of multi-year, high-resolution field measurements of the hybrid 6 MW/7.5MWh battery storage “M5Bat” to address this issue. This paper analyses and compares the cycles of the LSS and its individual battery technologies (two types of lead-acid and three types of lithium-ion batteries) after four years of FCR operation. An estimation of the cyclic ageing of the individual batteries is determined by referring to the equivalent full cycles (EFC) specified by the manufacturer. The data-based cycle analysis of the LSS and its individual battery technologies reveals that the participation in the reserve market exposes the storage system to a high number of cycles with a low average cycle depth of 1.69%. The EFC are small with an average of 0.278 and result in an average remaining number of EFC of the battery units after four years of 83.2%. The high number of residual cycles compared to the SOH of the battery units demonstrates the dominance of calendar ageing compared to cyclic ageing. The quality of the control software of the hybrid LSS as well as the individual battery units is decisive for the age-optimised operation of the storage system on the reserve market. The presented results can be used to investigate and model the influence of FCR operation on the ageing and state variable of the different battery technologies.

Engineering Poster E3: Developing Australia’s underground hydrogen storage through demonstration

Poster E3 For Australia to capitalise on the growing hydrogen (H2) economy, the current capability gap for large-scale, secure and cost-effective H2 storage must be addressed. Large-scale underground hydrogen storage (UHS) in porous reservoirs offers the required capacity to balance discrepancies between demand and supply over seasonal durations, and support decarbonisation and security in Australia’s energy system. This becomes essential for export and domestic markets from 2030 onwards. UHS in depleted gas fields can address the infrastructure and safety challenges, as well as supporting long-term supply security while decreasing delivery price through economies of scale. However, the technical readiness for Australia’s industries to undertake UHS is low, with scientific challenges around how stored H2 interacts with subsurface rocks and fluids, and how this impacts the storage efficiency. A commercially relevant demonstration of UHS is essential for providing the knowledge and confidence for large investment into commercial scale UHS. CO2CRC and CSIRO are collaboratively developing such a demonstration, utilising data and learnings from the Otway International Test Centre, as a proxy for commercial-scale UHS operations. To access the poster click the link on the right. To read the full paper click here

Concurrent 8. Presentation for: Collaborative development of the Northern Territory low-emissions carbon capture, utilisation and storage hub – a blueprint for the rapid decarbonisation of Northern Australia

Presented on Tuesday 17 May: Session 8 As the world increases its decarbonisation ambition, Australia is well placed to offer low emission intensity energy supplies to our region. Northern Australia’s plentiful resources mean that the region can be both an energy export and regional decarbonisation powerhouse. The Northern Territory has abundant natural gas and solar resources, significant carbon dioxide (CO2) storage capacity and proximity to international markets. This paper will summarise the development of the business case for a large-scale Carbon Capture, Utilisation and Storage (CCUS) hub based in the Northern Territory. The work is a result of a collaborative initiative to bring together experience and expertise from CSIRO, the Northern Territory Government, major gas industry emitters and engineering companies. The approach has been to develop a common vision of a low emission CCUS hub, develop an understanding of the key attributes of a hub, the development decisions, value drivers, market analysis and an understanding of potential economic outcomes that could be realised from its collaborative development. This work contemplates both initial and long-term economies of scale required to provide a pathway for decarbonisation of existing industries while providing opportunities for the development of new low-emission industries. To access the presentation click the link on the right. To read the full paper click here

Geological Hydrogen Storage: Geochemical Reactivity of Hydrogen with Sandstone Reservoirs.

The geological storage of hydrogen is necessary to enable the successful transition to a hydrogen economy and achieve net-zero emissions targets. Comprehensive investigations must be undertaken for each storage site to ensure their long-term suitability and functionality. As such, the systematic infrastructure and potential risks of large-scale hydrogen storage must be established. Herein, we conducted over 250 batch reaction experiments with different types of reservoir sandstones under conditions representative of the subsurface, reflecting expected time scales for geological hydrogen storage, to investigate potential reactions involving hydrogen. Each hydrogen experiment was paired with a hydrogen-free control under otherwise identical conditions to ensure that any observed reactions were due to the presence of hydrogen. The results conclusively reveal that there is no risk of hydrogen loss or reservoir integrity degradation due to abiotic geochemical reactions in sandstone reservoirs.

Concurrent 20. Presentation for: Suitability of depleted gas fields for underground hydrogen storage in Australia

Presented on Wednesday 18 May: Session 20 If there is a significant adoption of hydrogen in Australia as an energy carrier, it will be necessary to have storage options to buffer the fluctuations in supply and demand, both for domestic use and for export. For large-scale storage in a single location, underground hydrogen storage (UHS) is the preferred option for reasons of both cost and safety. The search for suitable sites for UHS will depend on the proximity to potential hydrogen generation, ports, and processing infrastructure, as well as CO2 storage options for blue hydrogen. Although UHS in salt caverns is an established technology, most of the suitable salt deposits in Australia (in the Canning Basin in WA, the Adavale Basin in Qld, and the Amadeus Basin in the NT) are not always well-located for production and transport. Depleted gas fields have been used previously for storage of hydrogen-rich gas mixtures as well as natural gas storage and appear to be the most promising and widely available UHS option in Australia. There appears to be sufficient storage capacity in depleted gas fields in most of the geographic areas with hydrogen production potential. However, there are still technical challenges to be addressed, such as the extent of possible contamination of the stored hydrogen with residual hydrocarbons, and the possible effects of geochemical reactions and microbial processes. To access the presentation click the link on the right. To read the full paper click here

Water Oxidation in the Presence of a Nickel Coordination Compound: Decomposition Products, Fe Impurity in the Electrolyte, and a Candidate as a Catalyst

Sustainable energy sources require a large-scale storage system. Water electrolysis toward hydrogen formation is a remarkable method for energy storage. However, oxygen-evolution reaction (OER) through water-oxidation reaction is a bottleneck in water-splitting systems. Different Ni-based molecular structures have been claimed to be OER catalysts. However, the impact of Ni (hydr)oxides formed by the degradation of Ni-based molecular structures on OER is a challenging issue. The effect of electrolyte impurity on OER in the presence of metal coordination compounds is rarely investigated. In this study, five important questions are considered regarding OER in the presence of a Ni coordination compound: (i) In which potential does the coordination compound start to be decomposed? (ii) After how many CVs does the decomposition occur? (iii) What is the effect of Fe impurity on OER in the presence of the Ni coordination compound? (iv) What is the product of the decomposition of the Ni coordination compound? (v) What is the true catalyst for OER in the presence of the Ni coordination compound? The roles of both the Fe impurity in the electrolyte and the Ni (hydr)oxide formed in the presence of a Ni coordination compound are investigated. The experiments showed that in the presence of the Ni coordination compound, Ni (hydr)oxide and Fe impurity in KOH formed a Ni–Fe oxide-based catalyst during OER, which is an efficient catalyst for OER. Fe impurity is a key contributor to observing OER in the presence of this Ni coordination compound.

Initial and residual trapping of hydrogen and nitrogen in Fontainebleau sandstone using nuclear magnetic resonance core flooding

Hydrogen is among a few promising energy carriers of the future mainly due to its zero-emission combustion nature. It also plays an important role in the transition from fossil fuel to renewable. Hydrogen technology is relatively immature and serious knowledge gaps do exist in its production, transport, storage, and utilization. Although the economical generation of hydrogen to the scale required for such transition is still the biggest technical and environmental challenge, unlocking the large-scale but safe storage is similarly important. It is difficult to store hydrogen in solid and liquid states and storing it in the gaseous phase requires a huge volume which is just available in subsurface porous media. Sandstone is the most abundant and favourable medium for such storage as carbonate rock might not be suitable due to potential geochemical reactions.It is well established in the literature that interaction of the host rock-fluid and injected gas plays a crucial role in fluid flow, residual trapping, withdrawal, and more generally storing capacity. Such data for the hydrogen system is extremely rare and are generally limited to contact angle measurements, while being not representative of the reality of rock-brine-hydrogen interaction(s). Therefore, we have conducted, for the first time, a series of core flooding experiments using Nuclear Magnetic Resonance (NMR) to monitor hydrogen (H2) and Nitrogen (N2) gas saturations during the drainage and imbibition stages under pressure and temperature that represent shallow reservoirs. To avoid any geochemical reaction during the test, we selected a clean sandstone core plug of 99.8% quartz (Fontainebleau with a gas porosity of 9.7% and a permeability of 190 mD).Results show significantly low initial and residual H2 saturations in comparison with N2, regardless of whether the injection flow rate or capillary number were the same or not. For instance, when the same injection flow rate was used, H2 saturation during primary drainage was 4% and it was <2% after imbibition. On other hand, N2 saturation during the primary drainage was 26% and it was 17% after imbibition. However, when the same capillary number of H2 was utilised for the N2 experiment, the N2 saturation values were ∼15% for initial gas saturation and 8% for residual gas saturation. Our results promisingly support the idea of hydrogen underground storage; however, we should emphasise that more sandstone rocks of different clay mineralogy should be investigated before reaching a conclusive outcome.