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Pathways toward a Decarbonized Future—Impact on Security of Supply and System Stability in a Sustainable German Energy System
Jan 2021
Publication
Pathways leading to a carbon neutral future for the German energy system have to deal with the expected phase-out of coal-fired power generation in addition to the shutdown of nuclear power plants and the rapid ramp-up of photovoltaics and wind power generation. An analysis of the expected impact on electricity market security of supply and system stability must consider the European context because of the strong coupling—both from an economic and a system operation point of view—through the cross-border power exchange of Germany with its neighbors. This analysis complemented by options to improve the existing development plans is the purpose of this paper. We propose a multilevel energy system modeling including electricity market network congestion management and system stability to identify challenges for the years 2023 and 2035. Out of the results we would like to highlight the positive role of innovative combined heat and power (CHP) solutions securing power and heat supply the importance of a network congestion management utilizing flexibility from sector coupling and the essential network extension plans. Network congestion and reduced security margins will become the new normal. We conclude that future energy systems require expanded flexibilities in combination with forward planning of operation.
Techno-economic Analysis of Hydrogen Electrolysis from Off-Grid Stand-Alone Photovoltaics Incorporating Uncertainty Analysis
Oct 2020
Publication
Solar-driven electrolysis of water to generate hydrogen is emerging as a viable strategy to decarbonize the global energy economy. However this direction is more expensive than traditional fossil fuel generation of hydrogen and effective pathways to lower this cost need to be identified. Here we report a Monte Carlo approach to explore a wide range of input assumptions to identify key cost drivers targets and localized conditions necessary for competitive stand-alone dedicated PV powered hydrogen electrolysis. We determine the levelized cost of hydrogen (LCOH) considering historical weather data for specific locations to model our PV system and optimize its size compared to the electrolyzer. This analysis and its methods show the potential for green hydrogen production using off-grid PV shows the merits of remote systems in areas of high solar resource and provides cost and performance targets for electrolyzer technologies.
Experimental Investigations Relevant for Hydrogen and Fission Product Issues Raised by the Fukushima Accident
Jan 2015
Publication
The accident at Japan's Fukushima Daiichi nuclear power plant in March 2011 caused by an earthquake and a subsequent tsunami resulted in a failure of the power systems that are needed to cool the reactors at the plant. The accident progression in the absence of heat removal systems caused Units 1-3 to undergo fuel melting. Containment pressurization and hydrogen explosions ultimately resulted in the escape of radioactivity from reactor containments into the atmosphere and ocean. Problems in containment venting operation leakage from primary containment boundary to the reactor building improper functioning of standby gas treatment system (SGTS) unmitigated hydrogen accumulation in the reactor building were identified as some of the reasons those added-up in the severity of the accident. The Fukushima accident not only initiated worldwide demand for installation of adequate control and mitigation measures to minimize the potential source term to the environment but also advocated assessment of the existing mitigation systems performance behavior under a wide range of postulated accident scenarios. The uncertainty in estimating the released fraction of the radionuclides due to the Fukushima accident also underlined the need for comprehensive understanding of fission product behavior as a function of the thermal hydraulic conditions and the type of gaseous aqueous and solid materials available for interaction e.g. gas components decontamination paint aerosols and water pools. In the light of the Fukushima accident additional experimental needs identified for hydrogen and fission product issues need to be investigated in an integrated and optimized way. Additionally as more and more passive safety systems such as passive autocatalytic recombiners and filtered containment venting systems are being retrofitted in current reactors and also planned for future reactors identified hydrogen and fission product issues will need to be coupled with the operation of passive safety systems in phenomena oriented and coupled effects experiments. In the present paper potential hydrogen and fission product issues raised by the Fukushima accident are discussed. The discussion focuses on hydrogen and fission product behavior inside nuclear power plant containments under severe accident conditions. The relevant experimental investigations conducted in the technical scale containment THAI (thermal hydraulics hydrogen aerosols and iodine) test facility (9.2 m high 3.2 m in diameter and 60 m3 volume) are discussed in the light of the Fukushima accident.
Assessment of an Innovative Way to Store Hydrogen in Vehicles
May 2019
Publication
The use of hydrogen as an alternative to fossil fuels for vehicle propulsion is already a reality. However due to its physical characteristics storage is still a challenge. There is an innovative way presented in this study to store hydrogen in conventional vehicles propelled by spark-ignition reciprocating engines and fuel cells using hydrogen as fuel; the storage of hydrogen will be at high pressure within small spheres randomly packed in a tank like the conventional tank of fuel used nowadays in current vehicles. Therefore the main purpose of the present study is to assess the performance of this storage system and compare it to others already applied by car manufacturers in their cars. In order to evaluate the performance of this storage system some parameters were taken into account: The energy stored by volume and stored by weight hydrogen leakage and compliance with current standards. This system is safer than conventional storage systems since hydrogen is stored inside small spheres containing small amounts of hydrogen. Besides its gravimetric energy density (GED) is threefold and the volumetric energy density (VED) is about half when compared with homologous values for conventional systems and both exceed the targets set by the U.S. Department of Energy. Regarding the leakage of hydrogen it complies with the European Standards provided a suitable choice of materials and dimensions is made.
Progress and Challenges on the Thermal Management of Electrochemical Energy Conversion and Storage Technologies: Fuel Cells, Electrolysers, and Supercapacitors
Oct 2021
Publication
It is now well established that electrochemical systems can optimally perform only within a narrow range of temperature. Exposure to temperatures outside this range adversely affects the performance and lifetime of these systems. As a result thermal management is an essential consideration during the design and operation of electrochemical equipment and can heavily influence the success of electrochemical energy technologies. Recently significant attempts have been placed on the maturity of cooling technologies for electrochemical devices. Nonetheless the existing reviews on the subject have been primarily focused on battery cooling. Conversely heat transfer in other electrochemical systems commonly used for energy conversion and storage has not been subjected to critical reviews. To address this issue the current study gives an overview of the progress and challenges on the thermal management of different electrochemical energy devices including fuel cells electrolysers and supercapacitors. The physicochemical mechanisms of heat generation in these electrochemical devices are discussed in-depth. Physics of the heat transfer techniques currently employed for temperature control are then exposed and some directions for future studies are provided.
Detection of Contaminants in Hydrogen Fuel for Fuel Cell Electrical Vehicles with Sensors—Available Technology, Testing Protocols and Implementation Challenges
Dec 2021
Publication
Europe’s low-carbon energy policy favors a greater use of fuel cells and technologies based on hydrogen used as a fuel. Hydrogen delivered at the hydrogen refueling station must be compliant with requirements stated in different standards. Currently the quality control process is performed by offline analysis of the hydrogen fuel. It is however beneficial to continuously monitor at least some of the contaminants onsite using chemical sensors. For hydrogen quality control with regard to contaminants high sensitivity integration parameters and low cost are the most important requirements. In this study we have reviewed the existing sensor technologies to detect contaminants in hydrogen then discussed the implementation of sensors at a hydrogen refueling stations described the state-of-art in protocols to perform assessment of these sensor technologies and finally identified the gaps and needs in these areas. It was clear that sensors are not yet commercially available for all gaseous contaminants mentioned in ISO14687:2019. The development of standardized testing protocols is required to go hand in hand with the development of chemical sensors for this application following a similar approach to the one undertaken for air sensors.
Renewable Hydrogen Potential for Low-carbon Retrofit of the Building Stocks
Dec 2015
Publication
Energy-related GHG emissions mainly from fossil fuels combustion account for around 70% of total emissions. Those emissions are the target of the recent sustainability policies. Indeed renewables exploitation is considered widely the weapon to deal with this challenge thanks to their carbon neutrality. But the biggest drawback is represented by the mismatching between their production and users consumption. The storage would be a possible solution but its viability consists of economic sustainability and energy process efficiency as well. The cutting edge technologies of batteries have not still solved these issues at the same time. So a paradigm shift towards the identification of an energy carrier as storage option the so called Power-to-Gas could be the viable solution. From viability to feasibility a mandatory step is required: the opportunity to integrate the new solution in the proven infrastructures system. Thus the recent studies on Hydrogen (H2) enrichment in Natural Gas demonstrating a lower environmental impact and an increase in energy performance are the base to build the hydrogen transition in the urban environment. The aim of this paper is to evaluate the environmental benefits at building and district scale.
High Energy Density Storage of Gaseous Marine Fuels: An Innovative Concept and its Application to a Hydrogen Powered Ferry
Apr 2020
Publication
The upcoming stricter limitations on both pollutant and greenhouse gases emissions represent a challenge for the shipping sector. The entire ship design process requires an approach to innovation with a particular focus on both the fuel choice and the power generation system. Among the possible alternatives natural gas and hydrogen based propulsion systems seem to be promising in the medium and long term. Nonetheless natural gas and hydrogen storage still represents a problem in terms of cargo volume reduction. This paper focuses on the storage issue considering compressed gases and presents an innovative solution which has been developed in the European project GASVESSEL® that allows to store gaseous fuels with an energy density higher than conventional intermediate pressure containment systems. After a general overview of natural gas and hydrogen as fuels for shipping a case study of a small Roll-on/Rolloff passenger ferry retrofit is proposed. The study analyses the technical feasibility of the installation of a hybrid power system with batteries and polymer electrolyte membrane fuel cells fuelled by hydrogen. In particular a process simulation model has been implemented to assess the quantity of hydrogen that can be stored on board taking into account boundary conditions such as filling time on shore storage capacity and cylinder wall temperature. The simulation results show that if the fuel cells system is run continuously at steady state to cover the energy need for one day of operation 140 kg of hydrogen are required. Using the innovative pressure cylinder at a storage pressure of 300 bar the volume required by the storage system assessed on the basis of the containment system outer dimensions is resulted to be 15.2 m3 with a weight of 2.5 ton. Even if the innovative type of pressure cylinder allows to reach an energy density higher than conventional intermediate pressure cylinders the volume necessary to store a quantity of energy typical for the shipping sector is many times higher than that required by conventional fuels today used. The analysis points out as expected that the filling process is critical to maximize the stored hydrogen mass and that it is critical to measure the temperature of the cylinder walls in order not to exceed the material limits. Nevertheless for specific application such as the one considered in the paper the introduction of gaseous hydrogen as fuel can be considered for implementing zero local emission propulsion system in the medium term.
Black TiO2 for Solar Hydrogen Conversion
Feb 2017
Publication
Titanium dioxide (TiO2 ) has been widely investigated for photocatalytic H2 evolution and photoelectrochemical (PEC) water splitting since 1972. However its wide bandgap (3.0–3.2 eV) limits the optical absorption of TiO2 for sufficient utilization of solar energy. Blackening TiO2 has been proposed as an effective strategy to enhance its solar absorption and thus the photocatalytic and PEC activities and aroused widespread research interest. In this article we reviewed the recent progress of black TiO2 for photocatalytic H2 evolution and PEC water splitting along with detailed introduction to its unique structural features optical property charge carrier transfer property and related theoretical calculations. As summarized in this review article black TiO2 could be a promising candidate for photoelectrocatalytic hydrogen generation via water splitting and continuous efforts are deserved for improving its solar hydrogen efficiency.
Polymer–Ceramic Composite Membranes for Water Removal in Membrane Reactors
Jun 2021
Publication
Methanol can be obtained through CO2 hydrogenation in a membrane reactor with higher yield or lower pressure than in a conventional packed bed reactor. In this study we explore a new kind of membrane with the potential suitability for such membrane reactors. Silicone–ceramic composite membranes are synthetized and characterized for their capability to selectively remove water from a mixture containing hydrogen CO2 and water at temperatures typical for methanol synthesis. We show that this membrane can achieve selective permeation of water under such harsh conditions and thus is an alternative candidate for use in membrane reactors for processes where water is one of the products and the yield is limited by thermodynamic equilibrium.
Russia’s Policy Transition to a Hydrogen Economy and the Implications of South Korea–Russia Cooperation
Dec 2021
Publication
Leading countries are developing clean energy to replace fossil fuels. In this context Russia is changing its energy policy towards fostering new energy resources such as hydrogen and helium. Hydrogen will not only contribute to Russia’s financial revenue by replacing natural gas but will also provide a basis for it to maintain its dominance over the international energy market by pioneering new energy markets. Russia is aiming to produce more than two million tons of hydrogen fuel for export to Europe and Asia by 2035. However it is facing many challenges including developing hydrogen fuel storage systems acquiring the technology required for exporting hydrogen and building trust in the fuel market. Meanwhile South Korea has a foundation for developing a hydrogen industry as it has the highest capacity in the world to produce fuel cells and the ability to manufacture LNG: (liquefied natural gas) carriers. Therefore South Korea and Russia have sufficient potential to create a new complementary and reciprocal cooperation model in the hydrogen fuel field. This study examines the present and future of Russia’s energy policy in this area as well as discusses South Korea and Russia’s cooperation plans in the hydrogen fuel sector and the related implications.
Everything About Hydrogen Podcast: Commercial Trucking at the Speed of Hydrogen
Jun 2021
Publication
The transportation and mobility sector is vast complex unwieldy and most excitingly an obvious area of focus for hydrogen fuel cell technology applications. Hydrogen FCEVs allow vehicles to run in a wide range of environments with zero tailpipe emissions and can do so without the need for extremely heavy battery cells and can be refueled in the same amount of time as a modern ICE vehicle. This makes hydrogen FCEVs an ideal fit for the heavy commercial transportation industry and is why Hyzon Motors has jumped at the opportunity to revolutionize the industry. The company has grabbed headlines all over the world with its ambitious plans for rolling out its trucks in the United States and other major markets. It has also made news with its recent announcement that the company is going public and has attracted significant investor interest. The EAH team is joined on this episode by Hyzon's CEO Craig Knight to talk about how the company is tackling some of the most significant challenges in decarbonizing transport and how it can make trucking a zero-emission operation.
The podcast can be found on their website
The podcast can be found on their website
Everything About Hydrogen Podcast: Giga-watt it Takes to Scale Green Hydrogen (and Ammonia)
Feb 2021
Publication
How do we get green hydrogen (and green ammonia) production to scale and make it cost competitive? It's a great question and we ask it all the time on the show. Well Alicia Eastman Co-founder & Managing Director of InterContinental Energy (ICE) may be one of the best authorities in the world on this topic and she joins us on this episode of EAH to tell the team all about her and ICE's work developing the Asian Renewable Energy Hub (AREH). Located in Western Australia the AREH when completed will be the largest renewable energy project by total generation capacity on the planet. At 26 GW it surpasses even the likes of the Three Gorges Dam and will act as a central production and distribution point for huge quantities of clean hydrogen and ammonia for offtakers and customers across APAC and beyond. The AREH is a truly massive project that has global implications for the global energy landscape of the future.
The podcast can be found on their website.
The podcast can be found on their website.
Everything About Hydrogen Podcast: Supplying the Building Blocks of an Energy Revolution
Apr 2021
Publication
On this episode of Everything About Hydrogen the team is joined by Sam French Business Development Director at JM who spent some time speaking with us about the transition from grey hydrogen to low-carbon generation technologies and what steps the UK - and countries all over the world - to use hydrogen as part of the pathway to a sustainable energy future.
The podcast can be found on their website
The podcast can be found on their website
Experimental Characterization of an Alkaline Electrolyser and a Compression System for Hydrogen Production and Storage
Aug 2021
Publication
Storing renewable energy in chemicals like hydrogen can bring various benefits like high energy density seasonal storability possible cost reduction of the final product and the potential to let renewable power penetrate other markets and to overcome their intermittent availability. In the last year’s production of this gas from renewable energy sources via electrolysis has grown its reputation as one feasible solution to satisfy future zero-emission energy demand. To extend the exploitation of Renewable Energy Source (RES) small-scale conversion plants seem to be an interesting option. In view of a possible widespread adoption of these types of plants the authors intend to present the experimental characterization of a small-scale hydrogen production and storage plant. The considered experimental plant is based on an alkaline electrolyser and an air-driven hydrogen compression and storage system. The results show that the hydrogen production-specific consumption is on average 77 kWh/kgH2 . The hydrogen compressor energy requirement is on average 15 kWh/kgH2 (data referred to the driving compressed air). The value is higher than data found in literature (4.4–9.3 kWh/kgH2 ) but the difference can be attributed to the small size of the considered compressor and the choice to limit the compression stages.
Modeling Hydrogen Refueling Infrastructure to Support Passenger Vehicles
May 2018
Publication
The year 2014 marked hydrogen fuel cell electric vehicles (FCEVs) first becoming commercially available in California where significant investments are being made to promote the adoption of alternative transportation fuels. A refueling infrastructure network that guarantees adequate coverage and expands in line with vehicle sales is required for FCEVs to be successfully adopted by private customers. In this paper we provide an overview of modelling methodologies used to project hydrogen refueling infrastructure requirements to support FCEV adoption and we describe in detail the National Renewable Energy Laboratory’s scenario evaluation and regionalization analysis (SERA) model. As an example we use SERA to explore two alternative scenarios of FCEV adoption: one in which FCEV deployment is limited to California and several major cities in the United States; and one in which FCEVs reach widespread adoption becoming a major option as passenger vehicles across the entire country. Such scenarios can provide guidance and insights for efforts required to deploy the infrastructure supporting transition toward different levels of hydrogen use as a transportation fuel for passenger vehicles in the United States.
Everything About Hydrogen Podcast: Could Electrolysers Replicate Moore's Law?
Apr 2020
Publication
On this weeks episode the team are talking all things hydrogen with Sebastian-Justus Schmidt Chairman of Enapter and Thomas Chrometzka Head of Strategy at Enapter. On the show we discuss Enapter’s Anion Exchange Membrane (AEM) electrolyser and why Enapter believe that their modular electrolyser approach will revolutionise the cost of green hydrogen. We also discuss the wide array of use cases and sectors that Enapter are already working with to provide their solution as well as their view on where the current barriers exist for the hydrogen market. All this and more on the show!
The podcast can be found on their website
The podcast can be found on their website
An Experimental Study of Propagating Spherical Flames in Unconfined Hydrogen-oxygen Explosions
Sep 2021
Publication
The study to understand the flame propagation behaviors of hydrogen-oxygen explosions is required to make a precise risk assessment. Moreover although research has investigated the propagating spherical flames in unconfined hydrogen-air explosions no study to date has examined the hydrogen-oxygen explosions. The spherical flame propagation in unconfined hydrogen-oxygen explosions have been investigated using a soap bubble method. In the present experiments hydrogen-oxygen mixtures were filled in a 10 cm diameter soap bubble and ignited by an electric spark at the center. The flame propagation behaviors were measured by a high-speed Schlieren photography. The laminar burning velocities and critical flame radii for the onset of flame acceleration in unconfined hydrogen-oxygen explosions were estimated. Results demonstrated that the laminar burning velocities of hydrogenoxygen mixtures were much faster than those of hydrogen-air mixtures. In addition the shift value of maximum laminar burning velocity for hydrogen-oxygen mixtures towards a leaner equivalence ratio is observed. The experimental flame speeds for all experiments were increased owing to diffusionalthermal and Darrieus-Landau instabilities although the measured flame radii were small. The critical flame radius corresponding to the onset of flame acceleration decreased with the decrease in equivalence ratio.
Effect of Hydrogen on Very High Cycle Fatigue Behavior of a Low-strength Cr-Ni-Mo-V Steel Containing Micro-defects
Dec 2017
Publication
The role of hydrogen in fatigue failure of low strength steels is not as well understood as of high strength steels in very high cycle fatigue regime. In this work axially cyclic tests on a low strength Cr-Ni-Mo-V steel with charged hydrogen were carried out up to the very high cycle fatigue regime under ultrasonic frequency to examine the degradation of fatigue strength and associated failure mechanisms. Results show that the S-N curves show a continuously decreasing mode and hydrogen-charged specimens have lower fatigue strength and shorter fatigue lifetime as compared with as-received specimens. It is concluded that the hydrogen trapped by inclusions drives interior micro-defects as dominant crack initiation site and has a clear link to the initiation and early growth of interior fatigue cracks.
Hydrogen-induced Failure of TiNi Based Alloy with Coarse-grained and Ultrafine-grained Structure
Jul 2016
Publication
The objective of this work is to investigate the effect of hydrogen-induced fracture of TiNi-based alloy. In this report we performed the first studies comparing inelastic properties and fracture of the specimens of the binary alloy of TiNi wire under the action of hydrogen with coarse-grained (CG) and ultrafine-grained (UFG) microstructure. It is shown that hydrogen embrittlement (HE) occurs irrespective of the grain size in the studied specimens at approximately equal strain values. However compared to the specimens with CG structure those with UFG structure accumulate two to three times more hydrogen for the same hydrogenation time. It is found that hydrogen has a much smaller effect on the inelastic properties of specimens with UFG structure as compared to those with CG structure.
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