The focus of the proposal is the use of hydrogen to store excess electrical energy generated off-peak from a renewable energy plant and its use for the generation of electricity at peak demand, that is, chemical energy storage.
Hydrogen is produced through electrolysis and photoelectrolysis, stored on site and used to generate electricity in a fuel cell. Our aim is to increase the cost-competitiveness of chemical energy storage using hydrogen by reducing the end-to-end costs of electricity produced from renewable sources, and the costs of electrolysis, storage and fuel cell technologies. At the same time, the objective is to increase efficiency and minimise the environmental impact. The ultimate objective of Unite!Energy is to prepare a new generation of creative, entrepreneurial, innovative researchers who can develop a successful career in the integration of hydrogen in the energy field. Researchers will be exposed to scientific and technological excellence, in highly reputed European technological universities.
The programme will be developed in an attractive institutional environment, shared by more than 200k students in Europe, with interdisciplinary research options, from more fundamental science to research in hybrid academic-industrial state-of-the-art facilities.
Quality assurance procedures will be implemented following those of the participating universities whose long relationship assures strong international networking among universities, research centres and industries (both large and SME) and sound training on transferable skills, which has become one of the pillars of education and innovation in partner academic institutions.
Objectives
To decrease the cost and environmental impact of the electrolyser-photoelectrolyser system (WP1) and fuel cell stack (WP2) maintaining or increasing their performances and stability.
To prepare a well-trained workforce with particular attention to the material science, design and sustainability assessment of processes (WP5).
To design and optimize system components to increase their efficiency and durability, considering safety-related aspects and by-products recycling (WP3).
To produce and disseminate high-quality scientific knowledge about chemical storage using hydrogen, and to increase social acceptance in hydrogen-based technologies (WP6).
To assess the environmental impacts, sustainability, and criticalities of the PtP solution and of each technology involved (WP4).
To create a strong university network based on the existing Unite! alliance and to reinforce the partnership with industrial entities that seek synergies between academia and stakeholders (WP7).
WORK PACKAGES
Three individual research projects (DCs 1-3) will focus on materials for electrolysers and functional techniques for their preparation, and one IRP (DC4) will study photoelectrocatalytic materials, using innovative low-energy techniques for their synthesis (WP1).
Three projects (DCs 5-7) will research the catalysts used in electrodes of a fuel cell and their processing (WP2). Four projects (DCs 8-11) will design and optimize the parts that comprise a PtP system (WP3).
Finally, one project (DC12) will evaluate the sustainability of the PtP solution (WP4). Through this doctoral network, the foundations will be built for an international doctoral school focused on innovation for energy storage using hydrogen.
WP1 Materials for H2 production
The capital expenditure (CAPEX) of green hydrogen production technologies is significantly higher than that of competitive state-of-the-art technologies. To achieve parity with fossil-based hydrogen, CAPEX should be reduced at least 35%[1], to decrease the price of green hydrogen from the current level of 4-7 €/kg to below 3 €/kg (assuming a feedstock 40 €/MWh and 4000 full load hours of operation). Green hydrogen can be produced from a variety of routes, the main one being electrolysis supported by various ways to exploit direct sunlight, e.g., photocatalysis.
[1] Green Hydrogen Cost Reduction: Scaling up Electrolysers to Meet the 1.5⁰C Climate Goal, International Renewable Energy Agency (IRENA), 2020.
The high cost of these techniques is due to high energy consumption and critical raw materials – platinum or platinum group metals (PGMs) – used to manufacture the components. These components also increase the life-cycle environmental impact of the produced hydrogen, so that in some cases it can be comparable to that of hydrogen produced using fossil fuels.
We will study possible solutions to decrease the price and the environmental footprint of hydrogen production through Task 1.1, investigating the replacement/decrease of PGM content in electrodes using carbon-based catalysts; Task 1.2, analysing the preparation route of the catalytic layer to decrease the energy required for electrodes manufacture and increase the efficient use of the catalytic layer; and Task 1.3, studying alternative electrolysers to commercial ones that are more efficient, such as protonic conducting ceramic steam electrolysers (PCC). These electrolysers are highly suitable for a PtP application as they allow to recirculate the steam generated in the fuel cell (by-product), which increases the overall process efficiency. The recirculation of heat (as steam) reduces needed energy for ensuring constant-temperature operation in the electrolyser. In parallel, we will study photocatalytic materials targeting to a solar conversion ratio higher than 10%, and effective lifetimes that are longer than 10 years (Task 1.4).
State-of-the-art
Novel solutions / Ambition of Unite!Energy
Task 1.1: Preparation and test of electrocatalytic materials for water splitting DC1 / PWR, TUDa (Heraeus)
IRP1 Carbon nanomaterials with encapsulated metal nanoparticles as electrocatalysts for water splitting
High PGMs content in electrolysers.
Metal nanoparticles tend to leach in the conditions of electrochemical reactions.
The interaction between metals and carbon is not well understood today.
Use of hybrid materials consisting of a carbon and a metallic phase, with low PGMs content.
Metal nanoparticles can be encapsulated in carbon structures, to protect them from degradation.
Comprehensive knowledge of the effects of metal nanoparticles and the carbon structure on activity, and the physical and chemical origins of interaction between carbon and metal phases.
Task 1.2: Catalyst layer optimisation DC2 / TU GRAZ, FAU (Heraeus)
IRP2 Catalyst layer optimisation for reducing noble metal contents in PEMEC
A high amount of energy is required for electrode manufacture.
The thickness of the catalyst layer significantly influences the overall resistance of the cell.
Focus on advanced techniques to reduce manufacturing times and enhancing the assembly process.
Development of a new measurement protocol with a porous transport electrode (PTE) to study technically relevant current density anode and cathode catalyst layers with a high experimental throughput.
Task 1.3 Study of innovative alternatives to commercial electrolysers DC3 / PoliTo, UPC (Snam)
IRP3 Proton ceramic cells (PCC) stacks for ultra-pure hydrogen productio
Reports of steam electrolysis with PCC are scarce and earlier ones were often limited to laboratory-scale button cells (<1 cm2).
Increase the TRL from 2 to 5 focusing on a stack level.
Task 1.4 Preparation and test of photoelectrocatalytic materials DC4 / UPC, PoliTo (Solaronix)
IRP4 Photoelectrocatalytic materials prepared by mechanochemical methods as photoelectrodes for hydrogen production
Known photocatalysts to date render hydrogen production yields in the range of sunlight that are too low to meet large-scale industrial requirements.
Mechanochemical synthesis of photoelectrocatalysts based on our previous studies with heterostructures of compounds of titanates or bismuth oxide.
WP2 Materials for energy generation
Currently, like hydrogen production, the use of hydrogen for energy generation cannot compete in costs with the price of electricity produced using fossil fuels. The CAPEX of a proton exchange membrane fuel cell (PEMFC) is now between 6000 (installation of a capacity up to 5 kWe) and 1900 €/kW (51-500 kWe), depending on the size of the application. The EU suggests a target CAPEX between 5000 and 1200 €/kW for 2024. Again, the high costs are caused by PGMs and energy needed to manufacture the fuel cell components. Thus, we have designed three IRPs.
[2] Table 21: KPIs for low temperature PEM stationary fuel cells (PEMFC), Clean Hydrogen JU, Strategic Research and Innovation Agenda 2021 – 2027.
The first in Task 2.1, studies lowering the platinum content or replacing/partially exchanging it with low-impact, cost-effective materials.
IRP in Task 2.2 explores surface coating processes (e.g., 3D-printing) for more efficient electrode manufacture, allowing higher current density and efficiency. The third individual project (Task 2.3) focuses on an innovative fuel cell (anion-exchange membrane fuel cell) using earth-abundant-element-based materials.
State-of-the-art
Novel solutions / Ambition of Unite!Energy
Task 2.1 Preparation and test of electrocatalytic materials for fuel cells DC5 / TUDa, PoliTo (Heraeus)
IRP5 Optimisation of FeNC catalysts for fuel cell application
Pt/C the bench-mark catalyst used in fuel cell (PEMFC), contributes about 50% to the costs of a FC stack.
To reach high current densities using FeNC, large catalyst loadings are required. This improves the reaction activity, but it causes problems in mass transport at high current densities.
Catalysts containing only earth abundant elements, FeNC (iron-nitrogen-carbon) can reach activities comparable with low-content Pt/C catalysts.
Overcoming this problem, e.g., by boosting FeNC catalyst performance with small quantities of precious metals, could provide a possible solution that still enables target values for commercialization to be met.
Task 2.2 Preparation and test of structured gas diffusion layers and carbon electrodes DC6 / INP GRENOBLE, PoliTo (CEA Grenoble) IRP6 Use of natural wood and biobased polymers as base materials for the elaboration of fuel cells components by additive manufacturing
Despite widespread use as both structural and functional materials in conventional devices (capacitors, batteries, etc.), biobased polymers still have a marginal role in additive manufacturing (AM). Since these materials have not been integrated in easily up-scalable production processes, their full potential for large-scale use is still to be demonstrated.
To design and create new composite materials adapted to liquid deposition modelling (LDM). Recent preliminary studies showed that structured carbon electrodes fabricated by 3D-printing followed by a carbonization step can provide a 5-fold increase in the current density generated by fuel cell electrodes. This paves the way for new high-performance devices with a tuneable shape and performance.
Task 2.3 Study of innovative alternatives to commercial fuel cells: alkaline membrane fuel cells DC7 / Aalto, KTH (Powercell) IRP7 Development of novel catalysts for hydrogen fuelled alkaline membrane fuel cells
Potentially the alkaline environment in AEMFC allow less noble catalyst compared to PEMFC. However, while for Pt/C electrodes the ORR activity in AEMFC is comparable with the ORR in PEMFC, the HOR is more sluggish in AEMFC.
More research is needed to enhance the development of the catalyst layer composition and structure to gain better electrode utilization and performance durability.
To find alternative HOR electrocatalysts with notable reduced PGMs content obtaining a high current density and after accelerated stability test the activity decrease is lower than 10%. We have recently obtained a significant improvement in AEM’s ion-conductivity and stability.
Establishing best interaction between catalyst and ionomer, and water management, enhancing technology and reach fuel cell activity of 2 A/cm2.
WP3 Systems design
By increasing the efficiency and service time of the technologies, it is possible to lower the total costs of a PtP application and to improve its total efficiency. Currently, the hydrogen production by using the surplus of renewable energy is considered an industrial activity, so there is no discount for electricity consumption. As a result, the operating expense (OPEX) are significantly higher than the competitive present technologies related to hydrogen production and power generation.
To increase the efficiency and useful life of the hydrogen production electrolyser stack-based system, its reliability should be improved by using advanced control systems effectively exploiting the time-varying renewable electricity supply; we will study this in Task 3.1.
Then the same concept will apply to the whole system (Task 3.2). As the efficiency of PtP is strongly related to the safety of hydrogen-related technologies, we aim to develop trust and acceptance of new technologies in this field.
Recently, several projects, like Preslhy, HySEA, H2Sense or HyTunnel-CS, have created the basis for hydrogen safety-related advances, especially hydrogen behaviour in accidental releases and their consequences. We will study innovative materials (Task 3.3) and configurations (Task 3.4) to avoid self-ignition in leakage.
State-of-the-art
Novel solutions / Ambition of Unite!Energy
Task 3.1 Design and optimisation of the electrolyser system DC8 / Aalto, PoliTo (ABB)
IRP8 Design and optimisation of converter-fed electrolyser system
Electrolyser stacks are supplied by thyristor converters, which results in very high harmonic distortion in the grid and electrolyser currents.
To develop a control method aimed at minimizing harmonics in the AC or DC bus.
The conventional topology is non-modular, so the available degrees of freedom for controlling and monitoring the electrolyser stack are very limited.
To design a new electrolyser concept, consisting of multiple stacks with their own dedicated power converters, which would improve the efficiency, lifetime, flexibility, and scalability.
Task 3.2 Design and optimisation of the whole system DC9 / UPC, KTH (eRoots)
IRP9 Green H2-electrolyser based industrial systems for supporting future power system
The progressive disconnection of conventional synchronous-based generation will require fast, innovative and reliable services to maintain the system frequency and voltage within the required limits under different contingencies and scenarios.
To develop intelligent algorithms to operate, control and coordinate electrolyser-based production facilities studying their future supporting role in the renewable-energy stabilisation
Task 3.3 Design and optimisation of safe materials for hydrogen storage DC10 / Aalto, UPC (EOS)
IRP10 Physics-informed artificial intelligence for assessing and designing safe materials for hydrogen storage
Despite their excellent mechanical properties, metallic materials drastically deteriorate due to H2 embrittlement (HE).
To understand this phenomenon and to design innovative hydrogen-resistant systems for the safe and large-scale use of hydrogen.
Establishing an understanding of the HE mechanisms required for hydrogen-tolerant materials development mainly utilises expensive and time-consuming advanced multiscale characterization techniques. This approach makes material development economically inefficient.
To complement these experimental techniques with digital tools, such as multiscale materials modelling to understand HE mechanisms comprehensively and efficiently apply artificial intelligence, to extract valuable knowledge for hydrogen-tolerant materials development.
Task 3.4 Ensuring safety operation for hydrogen storage DC11 / TUDa, UPC (BSC)
IRP11 Ensuring hydrogen safety operation through high performance computing and high-fidelity modelling
Hydrogen gas can self-ignite without the aid of an external energy source from leakages of pipes and tanks.
To design safe storage systems and safety protocols. We will prepare a simulation that can contribute to further establishing safe protocols for hydrogen operation.
WP4 Sustainability
In Unite!Energy, assessment of the sustainability of the technologies studied in the individual projects (Task 4.1) and of the total application (Task 4.2) are considered fundamental.
State-of-the-art
Novel solutions / Ambition of Unite!Energy
Task 4.1 Analyse environmental impacts and sustainability of the solution proposed by Unite!Energy (PoliTo/UPC)
More research is needed in the hydrogen sector on its sustainability and circularity, to define the effective reduction of impacts of the proposed solutions compared to state-of-the-art technologies with similar technical characteristics.
To analyse the impacts and sustainability of the solution proposed in each IRP and to compare them with those of related commercial technologies. A training system will be organized to provide PhD students with the theoretical bases and knowledge on life cycle assessment (LCA) and sustainability analysis, and a mentoring system.
Task 4.2 Assess the sustainability of the whole application DC12 / UPC, INP GRENOBLE (EIT InnoEnergy)
IRP12 A sustainable path towards the innovative deployment of low-carbon H2 technology
Large volume of data for LCA studies, which influences the quality of the life cycle inventory (LCI) and LCA study overall.
To create a LCA database related to the technologies studied for open LCA software, which will enable users to reduce time, efforts and resources for data collection, reflect supply chains they have no direct control over, and identify critical levers to conduct an eco-design approach.
For emerging technologies, e.g., innovative electrolysers and fuel cells, the challenge of dealing with uncertainty is great because these technologies have not been tested in a real operating environment.
To evaluate and compare scenarios based on the best quality of data, allowing a design choice based on sustainability.
Outputs, outcomes and impacts of Unite!Energy
