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HyDeploy2: Network Information and Maps
Jun 2021
Publication
Winlaton site was chosen as the site for the HyDeploy 2 North East trial as it was seen as the site that offered a high degree of variability with regards materials on the network size of network and statistical representation of housing. The Winlaton trial network is an estate of the wider Winlaton gas network situated in Blaydon near Gateshead. The Winlaton trial network has been isolated from the wider Winlaton gas network where it was previously supplied from and will be supplied with the blended gas from NGN’s Low Thornley gas depot with the installation of a brand-new pressure regulating district governor.<br/>The data contained within this report outlines the expected seasonal gas demand on the Winlaton trial network and the associated leakage and repair history for the network. No unusual repairs or leakage behaviour has been observed on this network. A DSEAR assessment has been conducted on the governor station ensuring ATEX compliance. The network isolation and reinforcement requirements are also given in this report highlighting the necessary actions to isolate the trial network from the wider Winlaton gas network. The NGN Safety Case outlines the risks associated with the operation of a gas grid and the ALARP mitigations developed to minimise them and what response is necessary in case such risks are realised. The existing safety case will be amended to account for the infrastructural operational and commercial changes associated with the HyDeploy 2 project. The report also contains a detailed register of all the assets on the Winlaton trial network this data set was used to inform the scientific research programme and specifically to allow an assessment to be carried out with regards to the operability of the existing and newly installed assets on the Winlaton trial network with respect to the blended gas.<br/>Click on supplement tab to view the other documents from this report
Renewable Power-to-Gas: A Technological and Economic Review
Aug 2015
Publication
The Power-to-Gas (PtG) process chain could play a significant role in the future energy system. Renewable electric energy can be transformed into storable methane via electrolysis and subsequent methanation. This article compares the available electrolysis and methanation technologies with respect to the stringent requirements of the PtG chain such as low CAPEX high efficiency and high flexibility. Three water electrolysis technologies are considered: alkaline electrolysis PEM electrolysis and solid oxide electrolysis. Alkaline electrolysis is currently the cheapest technology; however in the future PEM electrolysis could be better suited for the PtG process chain. Solid oxide electrolysis could also be an option in future especially if heat sources are available. Several different reactor concepts can be used for the methanation reaction. For catalytic methanation typically fixed-bed reactors are used; however novel reactor concepts such as three-phase methanation and micro reactors are currently under development. Another approach is the biochemical conversion. The bioprocess takes place in aqueous solutions and close to ambient temperatures. Finally the whole process chain is discussed. Critical aspects of the PtG process are the availability of CO2 sources the dynamic behaviour of the individual process steps and especially the economics as well as the efficiency.
Techno-Economic Analysis of a Novel Hydrogen-Based Hybrid Renewable Energy System for Both Grid-Tied and Off-Grid Power Supply in Japan: The Case of Fukushima Prefecture
Jun 2020
Publication
After the Great East Japan Earthquake energy security and vulnerability have become critical issues facing the Japanese energy system. The integration of renewable energy sources to meet specific regional energy demand is a promising scenario to overcome these challenges. To this aim this paper proposes a novel hydrogen-based hybrid renewable energy system (HRES) in which hydrogen fuel can be produced using both the methods of solar electrolysis and supercritical water gasification (SCWG) of biomass feedstock. The produced hydrogen is considered to function as an energy storage medium by storing renewable energy until the fuel cell converts it to electricity. The proposed HRES is used to meet the electricity demand load requirements for a typical household in a selected residential area located in Shinchi-machi in Fukuoka prefecture Japan. The techno-economic assessment of deploying the proposed systems was conducted using an integrated simulation-optimization modeling framework considering two scenarios: (1) minimization of the total cost of the system in an off-grid mode and (2) maximization of the total profit obtained from using renewable electricity and selling surplus solar electricity to the grid considering the feed-in-tariff (FiT) scheme in a grid-tied mode. As indicated by the model results the proposed HRES can generate about 47.3 MWh of electricity in all scenarios which is needed to meet the external load requirement in the selected study area. The levelized cost of energy (LCOE) of the system in scenarios 1 and 2 was estimated at 55.92 JPY/kWh and 56.47 JPY/kWh respectively
Instantaneous Hydrogen Production from Ammonia by Non-thermal Arc Plasma Combining with Catalyst
Jul 2021
Publication
Owing to the storage and transportation problems of hydrogen fuel exploring new methods of the realtime hydrogen production from ammonia becomes attractive. In this paper non-thermal arc plasma (NTAP) combining with NiO/Al2O3 catalyst is developed to produce hydrogen from ammonia with high efficiency and large scale. The effects of ammonia gas flow rate and discharge power on the gas temperature electron density the hydrogen production rate and energy efficiency were investigated. Experimental results show that the optical emission spectrum of NTAP working with pure ammonia medium was dominated by the atom spectrum of Hα Hβ and molecular spectrum of NH component. Under the optimum experimental condition of plasma discharge the highest energy efficiency of hydrogen production reached 783.4 L/kW·h at NH3 gas flow rate of 30 SLM. When the catalyst was added and heated by the NTAP simultaneously the energy efficiency further increased to 1080.0 L/kW·h.
The Implications of Ambitious Decarbonisation of Heat and Road Transport for Britain’s Net Zero Carbon Energy Systems
Oct 2021
Publication
Decarbonisation of heating and road transport are regarded as necessary but very challenging steps on the pathway to net zero carbon emissions. Assessing the most efficient routes to decarbonise these sectors requires an integrated view of energy and road transport systems. Here we describe how a national gas and electricity transmission network model was extended to represent multiple local energy systems and coupled with a national energy demand and road transport model. The integrated models were applied to assess a range of technologies and policies for heating and transport where the UK’s 2050 net zero carbon emissions target is met. Overall annual primary energy use is projected to reduce by between 25% and 50% by 2050 compared to 2015 due to ambitious efficiency improvements within homes and vehicles. However both annual and peak electricity demands in 2050 are more than double compared with 2015. Managed electric vehicle charging could save 14TWh/year in gas-fired power generation at peak times and associated emissions whilst vehicle-to-grid services could provide 10GW of electricity supply during peak hours. Together managed vehicle charging and vehicle-to-grid supplies could result in a 16% reduction in total annual energy costs. The provision of fast public charging facilities could reduce peak electricity demand by 17GW and save an estimated £650 million annually. Although using hydrogen for heating and transport spreads the hydrogen network costs between homeowners and motorists it is still estimated to be more costly overall compared to an all-electric scenario. Bio-energy electricity generation plants with carbon capture and storage are required to drive overall energy system emissions to net zero utilisation of which is lowest when heating is electrified and road transport consists of a mix of electric and hydrogen fuel-cell vehicles. The analysis demonstrates the need for an integrated systems approach to energy and transport policies and for coordination between national and local governments.
Reforming Processes for Syngas Production: A Mini-review on the Current Status, Challenges, and Prospects for Biomass Conversion to Fuels
Mar 2022
Publication
Dedicated bioenergy combined with carbon capture and storage are important elements for the mitigation scenarios to limit the global temperature rise within 1.5 °C. Thus the productions of carbon-negative fuels and chemicals from biomass is a key for accelerating global decarbonisation. The conversion of biomass into syngas has a crucial role in the biomass-based decarbonisation routes. Syngas is an intermediate product for a variety of chemical syntheses to produce hydrogen methanol dimethyl ether jet fuels alkenes etc. The use of biomass-derived syngas has also been seen as promising for the productions of carbon negative metal products. This paper reviews several possible technologies for the production of syngas from biomass especially related to the technological options and challenges of reforming processes. The scope of the review includes partial oxidation (POX) autothermal reforming (ATR) catalytic partial oxidation (CPO) catalytic steam reforming (CSR) and membrane reforming (MR). Special attention is given to the progress of CSR for biomass-derived vapours as it has gained significant interest in recent years. Heat demand and efficiency together with properties of the reformer catalyst were reviewed more deeply in order to understand and propose solutions to the problems that arise by the reforming of biomass-derived vapours and that need to be addressed in order to implement the technology on a big scale.
Everything About Hydrogen Podcast: A New Hope for Hydrogen?
Apr 2020
Publication
On this weeks episode the team discuss the Hydrogen Council the global stakeholder forum that has been at the forefront of efforts to advance the role of hydrogen and fuel cell technologies globally. We are excited to have as our guests Pierre-Etienne Franc Vice President for the Hydrogen Energy World Business Unit at Air Liquide and Stephan Herbst General Manager at Toyota Motor Europe. On the show we discuss why Air Liquide and Toyota decided to engage with the Council its strategy vision and perspective on the role that hydrogen can play in the energy transition and how companies can work with policymakers to enable this process. All this and more on the show!
The podcast can be found on their website
The podcast can be found on their website
Hydrogen and Hydrogen-derived Fuels through Methane Decomposition of Natural Gas – GHG Emissions and Costs
May 2020
Publication
Hydrogen can be produced from the decomposition of methane (also called pyrolysis). Many studies assume that this process emits few greenhouse gas (GHG) because the reaction from methane to hydrogen yields only solid carbon and no CO2. This paper assesses the life-cycle GHG emissions and the levelized costs for hydrogen provision from methane decomposition in three configurations (plasma molten metal and thermal gas). The results of these configurations are then compared to electrolysis and steam methane reforming (SMR) with and without CO2capture and storage (CCS). Under the global natural gas supply chain conditions hydrogen from methane decomposition still causes significant GHG emissions between 43 and 97 g CO2-eq./MJ. The bandwidth is predominately determined by the energy source providing the process heat i.e. the lowest emissions are caused by the plasma system using renewable electricity. This configuration shows lower GHG emissions compared to the “classical” SMR (99 g CO2-eq./MJ) but similar emissions to the SMR with CCS (46 g CO2-eq./MJ). However only electrolysis powered with renewable electricity leads to very low GHG emissions (3 g CO2-eq./MJ). Overall the natural gas supply is a decisive factor in determining GHG emissions. A natural gas supply with below-global average GHG emissions can lead to lower GHG emissions of all methane decomposition configurations compared to SMR. Methane decomposition systems (1.6 to 2.2 €/kg H2) produce hydrogen at costs substantially higher compared to SMR (1.0 to 1.2 €/kg) but lower than electrolyser (2.5 to 3.0 €/kg). SMR with CCS has the lowest CO2abatement costs (24 €/t CO2-eq. other > 141 €/t CO2-eq.). Finally fuels derived from different hydrogen supply options are assessed. Substantially lower GHG emissions compared to the fossil reference (natural gas and diesel/gasoline) are only possible if hydrogen from electrolysis powered by renewable energy is used (>90% less). The other hydrogen pathways cause only slightly lower or even higher GHG emissions.
Development of Liquid Hydrogen Leak Frequencies Using a Bayesian Update Process
Sep 2021
Publication
To quantify the risk of an accident in a liquid hydrogen system it is necessary to determine how often a leak may occur. To do this representative component leakage frequencies specific to liquid hydrogen can be determined as a function of the normalized leak size. Subsequently the system characteristics (e.g. system pressure) can be used to calculate accident consequences. Operating data (such as leak frequencies) for liquid hydrogen systems are very limited; rather than selecting a single leak frequency value from a literature source data from different sources can be combined using a Bayesian model. This approach provides leakage rates for different amounts of leakage distributions for leakage rates to propagate through risk assessment models to establish risk result uncertainty and a means for incorporating liquid hydrogen-specific leakage data with leakage frequencies from other fuels. Specifically other cryogenic fluids like liquefied natural gas are used as a baseline for the Bayesian analysis. This Bayesian update process is used to develop leak frequency distributions for different system component types and leak sizes. These leak frequencies can be refined as liquid hydrogen data becomes available and may then inform safety code requirements based on the likelihood of liquid hydrogen release for different systems.
Development of Renewable Energy Multi-energy Complementary Hydrogen Energy System (A Case Study in China): A Review
Aug 2020
Publication
The hydrogen energy system based on the multi-energy complementary of renewable energy can improve the consumption of renewable energy reduce the adverse impact on the power grid system and has the characteristics of green low carbon sustainable etc. which is currently a global research hotspot. Based on the basic principles of hydrogen production technology this paper introduces the current hydrogen energy system topology and summarizes the technical advantages of renewable energy complementary hydrogen production and the complementary system energy coordination forms. The problems that have been solved or reached consensus are summarized and the current status of hydrogen energy system research at home and abroad is introduced in detail. On this basis the key technologies of multi-energy complementation of hydrogen energy system are elaborated especially in-depth research and discussion on coordinated control strategies energy storage and capacity allocation energy management and electrolysis water hydrogen production technology. The development trend of the multi-energy complementary system and the hydrogen energy industry chain is also presented which provides a reference for the development of hydrogen production technology and hydrogen energy utilization of the renewable energy complementary system.
Modelling and Experimental Analysis of a Polymer Electrolyte Membrane Water Electrolysis Cell at Different Operating Temperatures
Nov 2018
Publication
In this paper a simplified model of a Polymer Electrolyte Membrane (PEM) water electrolysis cell is presented and compared with experimental data at 60 ◦C and 80 ◦C. The model utilizes the same modelling approach used in previous work where the electrolyzer cell is divided in four subsections: cathode anode membrane and voltage. The model of the electrodes includes key electrochemical reactions and gas transport mechanism (i.e. H2 O2 and H2O) whereas the model of the membrane includes physical mechanisms such as water diffusion electro osmotic drag and hydraulic pressure. Voltage was modelled including main overpotentials (i.e. activation ohmic concentration). First and second law efficiencies were defined. Key empirical parameters depending on temperature were identified in the activation and ohmic overpotentials. The electrodes reference exchange current densities and change transfer coefficients were related to activation overpotentials whereas hydrogen ion diffusion to Ohmic overvoltages. These model parameters were empirically fitted so that polarization curve obtained by the model predicted well the voltage at different current found by the experimental results. Finally from the efficiency calculation it was shown that at low current densities the electrolyzer cell absorbs heat from the surroundings. The model is not able to describe the transients involved during the cell electrochemical reactions however these processes are assumed relatively fast. For this reason the model can be implemented in system dynamic modelling for hydrogen production and storage where components dynamic is generally slower compared to the cell electrochemical reactions dynamics.
Optical, Electrical and Structural Study of Mg/Ti Bilayer Thin Film for Hydrogen Storage Applications
Apr 2021
Publication
Bilayer Mg/Ti (200 nm) thin films were successfully prepared by using D.C. magnetron sputtering unit. These films were vacuum annealed at 573 K temperature for one hour to obtain homogeneous and intermixed structure of bilayer. Hydrogenation of these thin film structures was made at different hydrogen pressure (15 30 & 45 psi) for 30 min to visualize the effect of hydrogen on film structure. The UV–Vis absorption spectra I-V characteristics and Raman spectroscopy were carried out to study the effect of hydrogen on optical electrical and structural properties of Mg/Ti bilayer thin films. The annealed thin film represents the semiconductor nature with the conductivity of the order of 10-5 Ώ−1-m−1 and it decreases as hydrogen pressure increases. The nonlinear dependence of resistivity on hydrogen pressure reveals inhomogeneous distribution of hydrogen in the thin film. Raman spectroscopy confirmed the presence of hydrogen in thin film where the intensity of peaks was found to be decreased with hydrogen pressure.
Toward Design of Synergistically Active Carbon-Based Catalysts for Electrocatalytic Hydrogen Evolution
Apr 2014
Publication
Replacement of precious catalyst with cost-effective alternatives would be significantly beneficial for hydrogen production via electrocatalytic hydrogen evolution reaction (HER). All candidates thus far are exclusively metallic catalysts which suffer inherent corrosion and oxidation susceptibility during acidic proton-exchange membrane electrolysis. Herein based on theoretical predictions we designed and synthesized nitrogen (N) and phosphorus (P) dual-doped graphene as a non-metallic electrocatalyst for sustainable and efficient hydrogen production. The N and Phetero-atoms could coactivate the adjacent C atom in the graphene matrix by affecting its valence orbital energy levels to induce a synergistically enhanced reactivity toward HER. As a result the dual-doped graphene showed higher electrocatalytic HER activity than single-doped ones and comparable performance to some of the traditional metallic catalysts.
Finding Synergy Between Renewables and Coal: Flexible Power and Hydrogen Production from Advanced IGCC Plants with Integrated CO2 Capture
Feb 2021
Publication
Variable renewable energy (VRE) has seen rapid growth in recent years. However VRE deployment requires a fleet of dispatchable power plants to supply electricity during periods with limited wind and sunlight. These plants will operate at reduced utilization rates that pose serious economic challenges. To address this challenge this paper presents the techno-economic assessment of flexible power and hydrogen production from integrated gasification combined cycles (IGCC) employing the gas switching combustion (GSC) technology for CO2 capture and membrane assisted water gas shift (MAWGS) reactors for hydrogen production. Three GSC-MAWGS-IGCC plants are evaluated based on different gasification technologies: Shell High Temperature Winkler and GE. These advanced plants are compared to two benchmark IGCC plants one without and one with CO2 capture. All plants utilize state-of-the-art H-class gas turbines and hot gas clean-up for maximum efficiency. Under baseload operation the GSC plants returned CO2 avoidance costs in the range of 24.9–36.9 €/ton compared to 44.3 €/ton for the benchmark. However the major advantage of these plants is evident in the more realistic mid-load scenario. Due to the ability to keep operating and sell hydrogen to the market during times of abundant wind and sun the best GSC plants offer a 6–11%-point higher annual rate of return than the benchmark plant with CO2 capture. This large economic advantage shows that the flexible GSC plants are a promising option for balancing VRE provided a market for the generated clean hydrogen exists.
Onboard Compressed Hydrogen Storage: Fast Filling Experiments and Simulations
Nov 2021
Publication
Technology safety represents a key enabling factor for the commercial use of hydrogen within the automotive industry. In the last years considerable pre-normative and normative research effort has produced regulations at national European and global level as well as international standards. Their validation is at the moment on going internationally. Additional research is required to improve this regulatory and standardization frame which is also expected to have a beneficial effect on cost and product optimization. The present paper addresses results related to the experimental assessment and modeling of safety performance of high pressure onboard storage. To simulate the lifetime of onboard hydrogen tanks commercial tanks have been subjected to filling-emptying cycles encompassing a fast-filling phase as prescribed by the European regulation on type-approval of hydrogen vehicles. The local temperature history inside the tanks has been measured and compared with the temperature outside at the tank metallic bosses which is the measurement location identified by the regulation. Experimental activities are complemented by computational fluid-dynamics (CFD) modeling of the fast-filling process by means of a numerical model previously validated. The outcome of these activities is a set of scientifically based data which will serve as input to future regulations and standards improvement.
Challenges in Hydrogen RCS’ Stakeholder Engagement in South Africa
Sep 2019
Publication
There is a great deal of knowledge and experience on the safe handling of hydrogen and the safe operation and management of hydrogen systems in South Africa. This knowledge and experience mostly sits within large gas supply companies and other large producers and consumers of hydrogen. However there appears to be less experience leading to a level of discomfort within regulatory bodies such as provincial and municipal fire departments and the national standards association. This compounded by a national policy of disallowing gas cylinders indoors has resulted in delays and indeed stalling in the process of obtaining permission to operate laboratories such as those of the national hydrogen programme HySA. In an effort to break this impasse two workshops were organised by HySA. The first was held at the CSIR’s facilities in Pretoria in October 2016. The second was held at the campus of the University of the Western Cape in Cape Town in May 2018. Four international experts and local experts in hydrogen regulations codes standards and safety addressed the 50-strong South African audiences via 5-way videoconferencing. This proved to be a very powerful tool to educate the audience and in particular the Tshwane (Pretoria) and Western Cape Fire Departments on the real issues risks and safety of hydrogen. The paper describes the South African Hydrogen RCS landscape the organisation and running of the workshops and the outputs achieved.
Hydrogen-based Systems for Integration of Renewable Energy in Power Systems: Achievements and Perspectives
Jul 2021
Publication
This paper is a critical review of selected real-world energy storage systems based on hydrogen ranging from lab-scale systems to full-scale systems in continuous operation. 15 projects are presented with a critical overview of their concept and performance. A review of research related to power electronics control systems and energy management strategies has been added to integrate the findings with outlooks usually described in separate literature. Results show that while hydrogen energy storage systems are technically feasible they still require large cost reductions to become commercially attractive. A challenge that affects the cost per unit of energy is the low energy efficiency of some of the system components in real-world operating conditions. Due to losses in the conversion and storage processes hydrogen energy storage systems lose anywhere between 60 and 85% of the incoming electricity with current technology. However there are currently very few alternatives for long-term storage of electricity in power systems so the interest in hydrogen for this application remains high from both industry and academia. Additionally it is expected that the share of intermittent renewable energy in power systems will increase in the coming decades. This could lead to technology development and cost reductions within hydrogen technology if this technology is needed to store excess renewable energy. Results from the reviewed projects indicate that the best solution from a technical viewpoint consists in hybrid systems where hydrogen is combined with short-term energy storage technologies like batteries and supercapacitors. In these hybrid systems the advantages with each storage technology can be fully exploited to maximize efficiency if the system is specifically tailored to the given situation. The disadvantage is that this will obviously increase the complexity and total cost of the energy system.<br/>Therefore control systems and energy management strategies are important factors to achieve optimal results both in terms of efficiency and cost. By considering the reviewed projects and evaluating operation modes and control systems new hybrid energy systems could be tailored to fit each situation and to reduce energy losses.
A Review at the Role of Storage in Energy Systems with a Focus on Power to Gas and Long-term Storage
Aug 2017
Publication
A review of more than 60 studies (plus m4ore than 65 studies on P2G) on power and energy models based on simulation and optimization was done. Based on these for power systems with up to 95% renewables the electricity storage size is found to be below 1.5% of the annual demand (in energy terms). While for 100% renewables energy systems (power heat mobility) it can remain below 6% of the annual energy demand. Combination of sectors and diverting the electricity to another sector can play a large role in reducing the storage size. From the potential alternatives to satisfy this demand pumped hydro storage (PHS) global potential is not enough and new technologies with a higher energy density are needed. Hydrogen with more than 250 times the energy density of PHS is a potential option to satisfy the storage need. However changes needed in infrastructure to deal with high hydrogen content and the suitability of salt caverns for its storage can pose limitations for this technology. Power to Gas (P2G) arises as possible alternative overcoming both the facilities and the energy density issues. The global storage requirement would represent only 2% of the global annual natural gas production or 10% of the gas storage facilities (in energy equivalent). The more options considered to deal with intermittent sources the lower the storage requirement will be. Therefore future studies aiming to quantify storage needs should focus on the entire energy system including technology vectors (e.g. Power to Heat Liquid Gas Chemicals) to avoid overestimating the amount of storage needed.
On the Climate Impacts of Blue Hydrogen Production
Nov 2021
Publication
Natural gas based hydrogen production with carbon capture and storage is referred to as blue hydrogen. If substantial amounts of CO2 from natural gas reforming are captured and permanently stored such hydrogen could be a low-carbon energy carrier. However recent research raises questions about the effective climate impacts of blue hydrogen from a life cycle perspective. Our analysis sheds light on the relevant issues and provides a balanced perspective on the impacts on climate change associated with blue hydrogen. We show that such impacts may indeed vary over large ranges and depend on only a few key parameters: the methane emission rate of the natural gas supply chain the CO2 removal rate at the hydrogen production plant and the global warming metric applied. State-of-the-art reforming with high CO2 capture rates combined with natural gas supply featuring low methane emissions does indeed allow for substantial reduction of greenhouse gas emissions compared to both conventional natural gas reforming and direct combustion of natural gas. Under such conditions blue hydrogen is compatible with low-carbon economies and exhibits climate change impacts at the upper end of the range of those caused by hydrogen production from renewable-based electricity. However neither current blue nor green hydrogen production pathways render fully “net-zero” hydrogen without additional CO2 removal.
Photocatalytic Hydrogen Production by Photo-Reforming of Methanol with One-pot Synthesized Pt-containing TiO2 Photocatalysts
Jul 2019
Publication
Functionalization of semiconductors by metallic nanoparticle is considered to be one of the most effective procedure to improve photocatalytic hydrogen production. Photodeposition is frequently used for functionalization but particle sizes and dispersions are still difficult to control. Here Pt functionalization is achieved in a one-pot synthesis. The as-prepared samples are compared to reference materials prepared by conventional photodeposition and our results confirm that small and well-dispersed nanoparticles with superior stability are obtained by one-pot synthesis. The enhanced stability is attributed to a limited leaching of Pt nanoparticles during illumination likely caused by the preferable interaction of small well dispersed Pt nanoparticles with the TiO2 support material. In addition our results demonstrate that Na-residues are detrimental for the photocatalytic performance and washing in acidic solution is mandatory to effectively reduce the sodium contamination.
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