Publications

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.

Due to its environmental impact the mobility system is increasingly under pressure. The challenges to cope with climate change air quality depleting fossil resources imply the need for a transition of the current mobility system towards a more sustainable one. Expectations and visions have been identified as crucial in the guidance of such transitions and more specifically of actor strategies. Still it remained unclear why the actors involved in transition activities appear to change their strategies frequently and suddenly. The empirical analysis of the expectations and strategies of three actors in the field of hydrogen and fuel cell technology indicates that changing actor strategies can be explained by rather volatile expectations related to different levels. Our case studies of the strategies of two large car manufacturers and the German government demonstrate that the car manufacturers refer strongly to expectations about the future regime while expectations related to the socio-technical landscape level appear to be crucial for the strategy of the German government.

Due to the simple structure and quick refueling process of the compressed hydrogen storage tank it is widely used in fuel cell vehicles at present. However temperature rise may lead to a safety problem during charging of a compressed hydrogen storage tank. To ensure the refueling safety the thermal effects need to be studied carefully during hydrogen refueling process. In this paper based on the mass and energy balance equations a general heat transfer model for refueling process of compressed hydrogen storage tank is established. According to the geometric model of the tank wall structure we have built three lumped parameter models: single-zone (hydrogen) dual-zone (hydrogen and tank wall) and triple-zone (hydrogen tank wall liner and shell) model. These three lumped parameter models are compared with U.S. Naval gas charging model and SAE MC method based refueling model. Under adiabatic and diathermic conditions four models are built in Matlab/Simulink software to simulate the hydrogen refueling process under corresponding conditions. These four models are: single-zone singletemperature (hydrogen) dual-zone single-temperature (hydrogen) dual-zone dual-temperature (hydrogen and tank wall temperatures) and triple-zone triple-temperature (hydrogen tank wall liner and tank wall shell temperatures). By comparing the analytical solution and numerical solution the temperature rise of the compressed hydrogen storage tank can be described. The analytical and numerical solutions on the heat transfer during hydrogen refueling process will provide theoretical guidance at actual refueling station so as to improve the refueling efficiency and to enhance the refueling safety.

The need to reduce the climate impact of the transport sector has led to an increasing interest in the utilisation of alternative fuels. Producing advanced fuels through the integration of anaerobic digestion and power-to-fuel technologies may offer a solution to reduce greenhouse gas emissions from difficult to decarbonise modes of transport such as heavy goods vehicles shipping and commercial aviation while also offering wider system benefits. This paper investigates the energy balance of power-to-fuel (power-to-methane power-to-methanol power-to-Fischer-Tropsch fuels) production integrated with a biogas facility co-digesting grass silage and dairy slurry. Through the integration of power-to-methane with anaerobic digestion an increase in system gross energy of 62.6% was found. Power-to-methanol integration with the biogas system increased the gross energy by 50% while power-to-Fischer-Tropsch fuels increased the gross energy yield by 32%. The parasitic energy demand for hydrogen production was highlighted as the most significant factor for integrated biogas and power-to-fuel facilities. Consuming electricity that would otherwise have been curtailed and optimising the anaerobic digestion process were identified as key to improving the energetic efficiency of all system configurations. However the broad cross-sectoral benefits of the overarching cascading circular economy system such as providing electrical grid stability and utilising waste resources must also be considered for a comprehensive perspective on the integration of anaerobic digestion and power-to-fuel.

Hydrogen-based technologies are among the most promising solutions to fulfill the zero-emission scenario and ensure the energy independence of many countries. Hydrogen is considered a green energy carrier which can be utilized in the energy transport and chemical sectors. However efficient and safe large-scale hydrogen storage is still challenging. The most frequently used hydrogen storage solutions in industry i.e. compression and liquefaction are highly energy-consuming. Underground hydrogen storage is considered the most economical and safe option for large-scale utilization at various time scales. Among underground geological formations salt caverns are the most promising for hydrogen storage due to their suitable physicochemical and mechanical properties that ensure safe and efficient storage even at high pressures. In this paper recent advances in underground storage with a particular emphasis on salt cavern utilization in Europe are presented. The initial experience in hydrogen storage in underground reservoirs was discussed and the potential for worldwide commercialization of this technology was analyzed. In Poland salt deposits from the north-west and central regions (e.g. Rogóźno Damasławek Łeba) are considered possible formations for hydrogen storage. The Gubin area is also promising where 25 salt caverns with a total capacity of 1600 million Nm3 can be constructed.

The safety factor of a composite structure in relation to its mechanical rupture is an important criterion for the safety of a 70 MPa composite pressure vessel for hydrogen storage particularly for on-board applications (car bus truck train…). After an introduction of Type IV technology the contribution of carbon fibre composite material structure manufacturing process of pressure vessels and environmental effects on the safety factor are commented. Thanks to an experimental-based evaluation on composite material and H2 composite pressure vessel the safety margins are addressed.

Hydrogen will play a pivotal role in achieving an affordable clean and prosperous economy. Hydrogen allows for cost-efficient bulk transport and storage of renewable energy and can decarbonise energy use in all sectors.

The European Union together with North Africa Ukraine and other neighbouring countries have a unique opportunity to realise a green hydrogen system. Europe including Ukraine has good renewable energy resources while North Africa has outstanding and abundant resources. Europe can re-use its gas infrastructure with interconnections to North-Africa and other countries to transport and store hydrogen. And Europe has a globally leading industry for clean hydrogen production especially in electrolyser manufacturing.

If the European Union in close cooperation with its neighbouring countries wants to build on these unique assets and create a world leading industry for renewable hydrogen production the time to act is now. Dedicated and integrated multi GW green hydrogen production plants will thereby unlock the vast renewable energy potential.

We the European hydrogen industry are committed to maintaining a strong and world-leading electrolyser industry and market and to producing renewable hydrogen at equal and eventually lower cost than low-carbon (blue) hydrogen. A prerequisite is that a 2x40 GW electrolyser market in the European Union and its neighbouring countries (e.g. North Africa and Ukraine) will develop as soon as possible.

A roadmap for 40 GW electrolyser capacity in the EU by 2030 shows a 6 GW captive market (hydrogen production at the demand location) and 34 GW hydrogen market (hydrogen production near the resource). A roadmap for 40 GW electrolyser capacity in North Africa and Ukraine by 2030 includes 7.5 GW hydrogen production for the domestic market and a 32.5 GW hydrogen production capacity for export.

If a 2x40 GW electrolyser market in 2030 is realised alongside the required additional renewable energy capacity renewable hydrogen will become cost competitive with fossil (grey) hydrogen. GW-scale electrolysers at wind and solar hydrogen production sites will produce renewable hydrogen cost competitively with low-carbon hydrogen production (1.5-2.0 €/kg) in 2025 and with grey hydrogen (1.0-1.5 €/kg) in 2030.

By realizing 2x40 GW electrolyser capacity producing green hydrogen about 82 million ton CO₂  emissions per year could be avoided in the EU. The total investments in electrolyser capacity will be 25-30 billion Euro creating 140000- 170000 jobs in manufacturing and maintenance of 2x40 GW electrolysers.

The industry needs the European Union and its member states to design create and facilitate a hydrogen market infrastructure and economy. Crucial is the design and realisation of new unique and long-lasting mutual co-operation mechanisms on political societal and economic levels between the EU and North Africa Ukraine and other neighbouring countries.

The unique opportunity for the EU and its neighbouring countries to develop a green hydrogen economy will contribute to economic growth the creation of jobs and a sustainable affordable and fair energy system. Building on this position Europe and its neighbours can become world market leaders for green hydrogen production technologies.

The UK is investigating supplying hydrogen to homes and businesses instead of natural gas by “repurposing” the gas network. It presents a major engineering challenge which has never been done anywhere else in the world.

In a new report titled ‘Transitioning to hydrogen’ experts from a cross-professional engineering institution (PEI) working group including the IET have assessed the engineering risks and uncertainties and concluded there is no reason why repurposing the gas network to hydrogen cannot be achieved. But there are several engineering risks and uncertainties which need to be addressed.

Through the combustion of fossil fuels the transport sector is responsible for 20-30% of global CO2 emissions. We can support the net-zero one ambition by decarbonising transport modes using green hydrogen fuelled options – hydrogen generated from renewable energy sources such as offshore wind.<br/><br/>We have been working with clients across the hydrogen industry for several years specifically around the generation dispatch and use of hydrogen within energy systems. However interest is swiftly moving to wider hydrogen based solutions including within the fleet rail aviation and maritime sectors.<br/><br/>Our latest ‘Future of Energy’ series explores the opportunity for green fuelled hydrogen transport. We look at each industry in detail the barriers to uptake market conditions and look at how the transport industry could adapt and develop to embrace a net-zero future.

In this review we primarily analyze the hydrogen production technologies based on water and biomass including the economic technological and environmental impacts of different types of hydrogen production technologies based on these materials and comprehensively compare them. Our analyses indicate that all renewable energy-based approaches for hydrogen production are more environmentally friendly than fossil-based hydrogen generation approaches. However the technical ease and economic efficiency of hydrogen production from renewable sources of energy needs to be further improved in order to be applied on a large scale. Compared with other renewable energy-based methods hydrogen production via biomass electrolysis has several advantages including the ease of directly using raw biomass. Furthermore its environmental impact is smaller than other approaches. Moreover using a noble metal catalyst-free anode for this approach can ensure a considerably low power consumption which makes it a promising candidate for clean and efficient hydrogen production in the future.