Publications

Concerns about climate change air pollution and the depletion of oil resources have prompted authorities to enforce increasingly strict rules in the automotive sector. There are several benefits to implementing fuel cell hybrid vehicles (FCHV) in the transportation sector including the ability to assist in reducing greenhouse gas emissions by replacing fossil fuels with hydrogen as energy carriers. This paper examines different control strategies for optimizing the power split between the battery and PEM fuel cell in order to maximize the PEM fuel cell system efficiency and reduce fuel consumption. First the vehicle and fuel cell system models are described. A forward approach is considered to model the vehicle dynamics while a semi-empirical and quasi-static model is used for the PEM fuel cell. Then different rule-based control strategies are analyzed with the aim of maximizing fuel cell system efficiency while ensuring a constant battery state of charge (SOC). The different methods are evaluated while the FCHV is performing both low-load and high-load drive cycles. The hydrogen consumption and the overall fuel cell system efficiency are considered for all testing conditions. The results highlight that in both low-load cycles and high-load cycles the best control strategies achieve a fuel cell system efficiency equal or greater to 33% while achieving a fuel consumption 30% less with respect to the baseline control strategy in low-load drive cycles.

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!

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Hydrogen has received tremendous global attention as an energy carrier and an energy storage system. Hydrogen carrier introduces a power to hydrogen (P2H) and power to hydrogen to power (P2H2P) facility to store the excess energy in renewable energy storage systems with the facts of large-scale storage capacity transportability and multiple utilities. This work examines the techno-economic feasibility of hybrid solar photovoltaic (PV)/hydrogen/fuel cell-powered cellular base stations for developing green mobile communication to decrease environmental degradation and mitigate fossil-fuel crises. Extensive simulation is carried out using a hybrid optimization model for electric renewables (HOMER) optimization tool to evaluate the optimal size energy production total production cost per unit energy production cost and emission of carbon footprints subject to different relevant system parameters. In addition the throughput and energy efficiency performance of the wireless network is critically evaluated with the help of MATLAB-based Monte-Carlo simulations taking multipath fading system bandwidth transmission power and inter-cell interference (ICI) into consideration. Results show that a more stable and reliable green solution for the telecommunications sector will be the macro cellular basis stations driven by the recommended hybrid supply system. The hybrid supply system has around 17% surplus electricity and 48.1 h backup capacity that increases the system reliability by maintaining a better quality of service (QoS). To end the outcomes of the suggested system are compared with the other supply scheme and the previously published research work for justifying the validity of the proposed system.

In the present scenario much importance has been provided to hydrogen energy systems (HES) in the energy sector because of their clean and green behavior during utilization. The developments of novel techniques and materials have focused on overcoming the practical difficulties in the HES (production storage and utilization). Comparatively considerable attention needs to be provided in the hydrogen storage systems (HSS) because of physical-based storage (compressed gas cold/cryo compressed and liquid) issues such as low gravimetric/volumetric density storage conditions/parameters and safety. In material-based HSS a high amount of hydrogen can be effectively stored in materials via physical or chemical bonds. In different hydride materials Mg-based hydrides (Mg–H) showed considerable benefits such as low density hydrogen uptake and reversibility. However the inferior sorption kinetics and severe oxidation/contamination at exposure to air limit its benefits. There are numerous kinds of efforts like the inclusion of catalysts that have been made for Mg–H to alter the thermodynamic-related issues. Still those efforts do not overcome the oxidation/contamination-related issues. The developments of Mg–H encapsulated by gas-selective polymers can effectively and positively influence hydrogen sorption kinetics and prevent the Mg–H from contaminating (air and moisture). In this review the impact of different polymers (carboxymethyl cellulose polystyrene polyimide polypyrrole polyvinylpyrrolidone polyvinylidene fluoride polymethylpentene and poly(methyl methacrylate)) with Mg–H systems has been systematically reviewed. In polymer-encapsulated Mg–H the polymers act as a barrier for the reaction between Mg–H and O2/H2O selectively allowing the H2 gas and preventing the aggregation of hydride nanoparticles. Thus the H2 uptake amount and sorption kinetics improved considerably in Mg–H.

Germany’s energy transition known as ‘Energiewende’ was always very progressive. However it came technically to a halt at the question of large-scale seasonal energy storage for wind and solar which was not available. At the end of the 2000s we combined our knowledge of both electrical and process engineering imitated nature by copying photosynthesis and developed Power-to-Gas by combining water electrolysis with CO2 -methanation to convert water and CO2 together with wind and solar power to synthetic natural gas. Storing green energy by coupling the electricity with the gas sector using its vast TWh-scale storage facility was the solution for the biggest energy problem of our time. This was the first concept that created the term ‘sector coupling’ or ‘sectoral integration’. We first implemented demo sites presented our work in research industry and ministries and applied it in many macroeconomic studies. It was an initial idea that inspired others to rethink electricity as well as eFuels as an energy source and energy carrier. We developed the concept further to include Power-to-Liquid Power-to-Chemicals and other ways to ‘convert’ electricity into molecules and climate-neutral feedstocks and named it ‘Power-to-X’ at the beginning of the 2010s.

This paper presents an experimental study of a hydrogen fusible link developed for use in the detection of hydrogen and in the activation of passive ventilation or other safety systems. Fusible links are commonly used to passively close fire dampers in the event of a fire; they generally consist of two pieces of metal joined together by a low temperature alloy to form a single device. When exposed to fire the link will heat up and eventually melt the alloy causing the metal pieces to separate. The same principle has been adopted for the hydrogen fusible link in which hydrogen recombiner catalyst was coated onto small rectangular brass plates. These plates were then soldered together to create prototypes of the hydrogen fusible link. When the resulting link is exposed to a hydrogen-air mixture an exothermic reaction occurs on the catalyst surface that will heat up the link and melt the solder separating the two sections of the hydrogen fusible link. A series of experiments was performed to characterize the thermal response of the hydrogen fusible links to various hydrogen-air mixtures. The effect of both hydrogen concentration and its rate of accumulation on the increase of catalyst temperature was examined. This study demonstrated the applicability of the hydrogen fusible link for managing hydrogen risk.

The demand for hydrogen has grown more than threefold since 1975 [1] and price is expected to significantly decrease by 2030 [2] concluding in an expected continual increase in demand. HyLaw defined by Hydrogen Europe lays out recommendations for hydrogen applications using identified Legal and Administrative Processes (LAPs) across 18 European countries. Regarding site location HyLaw refers to the land use plan. This defines the production and storage of hydrogen as an industrial activity and therefore regardless of the specific site methods of production or use the hydrogen site must be within a permitted industrial zone or under specific condition commercial areas [3]. Local authorities fire departments and other concerned parties may need to be consulted on site suitability for the project. Risktec explores a range of considerations for siting and layout of hydrogen developments including co-location with other assets for example with renewable energy sources hazardous facilities or public structures. Good practice tools and assessment techniques are presented to mitigate the risks associated with the production storage and use of hydrogen not just the surrounding site and environment but the operatives of the facility.

Maritime transport accounts for around 3% of global anthropogenic Greenhouse gas (GHG) emissions (Well-to-Wake) and these emissions must be reduced with at least 50% in absolute values by 2050 to contribute to the ambitions of the Paris agreement (2015). Zero carbon fuels made from renewable sources (hydro wind or solar) are by many seen as the most promising option to deliver the desired GHG reductions. For the maritime sector these fuels come in two forms: First as E-Hydrogen or E-Ammonia; Second as Hydrocarbon E-fuels in the form of E-Diesel E-LNG or E-Methanol. We evaluate emissions energy use and cost for E-fuels and find that the most robust path to these fuels is through dual-fuel engines and systems to ensure flexibility in fuel selection to prepare for growing supplies and lower risks. The GHG reduction potential of E-fuels depends entirely on abundant renewable electricity.

This study shows the results for the first time of an glycerol alkaline-acid electrolyzer. Such a configuration allows spontaneous operation producing energy and hydrogen simultaneously as a result of the utilization of the neutralization and fuel chemical energy. The electroreformer—built with a 20 wt% Pd/C anode and cathode and a Na+ -pretreated Nafion® 117—can simultaneously produce hydrogen and electricity in the low current density region whereas it operates in electrolysis mode at high current densities. In the spontaneous region the maximum power densities range from 1.23 mW cm−2 at 30 ◦C to 11.9 mW cm−2 at 90 ◦C with a concomitant H2 flux ranging from 0.0545 STP m−3 m−2 h −1 at 30 ◦C to 0.201 STP m−3 m−2 h −1 at 90 ◦C due to the beneficial effect of the temperature on the performance. Furthermore over a chronoamperometric test the electroreformer shows a stable performance over 12 h. As a challenge proton crossover from the cathode to the anode through the cation exchange Nafion® partially reduces the pH gradient responsible for the extra electromotive force thus requiring a less permeable membrane.

In Japan both CO2 (Carbon dioxide) emission reduction and energy security are the very important social issues after Fukushima Daiichi accident. On the other hand FCV (Fuel Cell Vehicle) using hydrogen will be on the market in 2015. Introducing large mass hydrogen energy is being expected as expanding hydrogen applications or solution to energy issues of Japan. And then the Japanese government announced the road map for introducing hydrogen energy supply chain in this June2014. Under these circumstances imported CO2 free hydrogen will be one of the solutions for energy security and CO2 reduction if the hydrogen price is affordable. To achieve this Kawasaki Heavy Industries Ltd. (KHI) performed a feasibility study on CO2-free hydrogen energy supply chain from Australian brown coal linked with CCS (Carbon dioxide Capture and Storage) to Japan. In the study hydrogen production systems utilizing brown coal gasification and LH2 (liquid hydrogen) systems as storing and transporting hydrogen are examined. This paper shows the possibility of realizing the CO2 free hydrogen supply chain the cost breakdown of imported hydrogen cost its cost competitiveness with conventional fossil and LH2 systems as key technologies of the hydrogen energy chain.