Publications

Commercialization of proton exchange membrane fuel cells can only materials provided its performance is closely related to existing technologies useful in commercial application. Other critical parameters like the utilization of cheaper materials should be taken into account during the manufacturing of the cell. A key component in the cell that has direct correlation to the cell perfor‐ mance is the flow plate. The weight coupled with cost of the cell revolves around the flow plate used in the manufacturing of the cell. This study explores materials ideal for the manufacturing of fuel cells in order to improve the overall cell performance. The investigation highlights the critical impact of varying materials used in the manufacturing of flow plates for PEM fuel cells. Stainless steel (SS) aluminium (Al) and copper (Cu) were the materials considered. The flow plate designs considered were serpentine and open pore cellular foam channel. Machine learning using python for the validation of the results with Linear regression Ridge regression and Polynomial regression algorithm was carried out. The performance of both flow field channels was compared using dif‐ ferent bipolar plate materials. The results show that metal foam flow channels overall performance was better than serpentine flow channels with all the various bipolar plate material used and Al material outperformed Cu and SS material. There is a direct correlation in terms of the outcome of the study and literature based on the data generated experimentally. It can however be concluded that molecules of hydrogen are stable on aluminium plates compared to copper and stainless steel

With future regulations on the horizon port authorities and ship owners/operators are looking at alternative propulsion solutions to reduce emission. Fuel cell technology provides an attractive zeroemission solution to generate electric power on board using hydrogen as a fuel. Fuel cell systems are scalable from 200kW to multi-MW providing high efficiency dispatchable clean quiet power generation. Several innovative pilot projects are on the way to demonstrate the marine application of this proven technology. Electrification of propulsion systems is advancing and fuel cell technology provides the opportunity to produce on board large quantity of power with zero-emission using hydrogen as a fuel. We will present the value proposition of having a fuel cell power generator on board of an electric vessel while discussing the safety considerations with the fuel cell module and the onboard fuel storage. We will present some of our current fuel cell marine projects and review some of the product development considerations including system architecture and safety as well as hydrogen supply and on-board fuel storage.

This paper discusses the optimal control of pressure using the zero-gradient control (ZGC) approach. It is applied for the first time in the study to control the optimal pressure of hydrogen natural gas mixture in an inclined pipeline. The solution to the flow problem is first validated with existing results using the Taylor series approximation regression analysis and the Runge-Kutta method combined. The optimal pressure is then determined using ZGC where the optimal set points are calculated without having to solve the non-linear system of equations associated with the standard optimization problem. It is shown that the mass ratio is the more effective parameter compared to the initial pressure in controlling the maximum variation of pressure in a gas pipeline.

Hydrogen is seen as an important future energy carrier as part of the move away from traditional hydrocarbon sources. Delayed ignition of a hydrogen-air mixture formed from an accidental release of hydrogen in either a confined or congested environment can lead to the generation of overpressure impacting both people and assets. An understanding of the possible overpressures generated is critical in designing facilities and effective mitigation systems against hydrogen explosion hazards. This paper describes the numerical modelling of hydrogen deflagrations using a new application PDRFOAM-R that is part of the wider OpenFOAM open-source CFD package of routines for the solution of systems of partial differential equations. The PDRFOAM-R code solves momentum and continuity equations the combustion model is based on flame area transport and the turbulent burning velocity correlation is based on Markstein and Karlovitz numbers. PDRFOAM-R is derived from publicly available PDRFOAM tool and it resolves small and large obstacles unlike PDRFOAM which is based on the Porosity Distributed Resistance approach. The PDRFOAM-R code is validated against various unconfined-uncongested and semi-confined congested explosion experiments. The flame dynamics and pressure history predicted from the simulation show a reasonable comparison with the experiments.

Hydrogen is a carbon-free fuel that can be produced in many ways starting from different sources. Its use as a fuel in internal combustion engines could be a method of significantly reducing their environmental impact. In spark-ignition (SI) engines lean hydrogen–air mixtures can be burnt. When a gaseous fuel like hydrogen is port-injected in an SI engine working with lean mixtures supercharging becomes very useful in order not to excessively penalize the engine performance. In this work the performance of a turbocharged PFI spark-ignition engine fueled by hydrogen has been investigated by means of 1-D numerical simulations. The analysis focused on the engine behavior both at full and partial load considering low and medium engine speeds (1500 and 3000 rpm). Equivalence ratios higher than 0.35 have been considered in order to ensure acceptable cycle-to-cycle variations. The constraints that ensure the safety of engine components have also been respected. The results of the analysis provide a guideline able to set up the load control strategy of a SI hydrogen engine based on the variation of the air to fuel ratio boost pressure and throttle opening. Furthermore performance and efficiency of the hydrogen engine have been compared to those of the base gasoline engine. At 1500 and 3000 rpm except for very low loads the hydrogen engine load can be regulated by properly combining the equivalence ratio and the boost pressure. At 3000 rpm the gasoline engine maximum power is not reached but for each engine load lean burning allows the hydrogen engine achieving much higher efficiencies than those of the gasoline engine. At full load the maximum power output decreases from 120 kW to about 97 kW but the engine efficiency of the hydrogen engine is higher than that of the gasoline one for each full load operating point.

In 2021 only 6 hydrogen fuelling station have been built in Italy of which 3 are not operational and only 1 is open to the public while the rest are built in private or industrial areas. While fuelling station which store more than 5000 kg of hydrogen are subjected to the “Seveso Directive” the permitting procedure for refuelling station which store less than the threshold is supervised by the fire brigade command of the province where the station is built. Recently in the effort to easy the permitting procedure to establish new stations a Ministerial Decree was published in the official gazette of the Italian Republic which lists minimum safety features and safety distances that if respected guarantee the approval by the authority. Nevertheless the imposed distances are such that the land required to build the station constitute a barrier rather than a facilitation. Exploiting the possibility introduced by the Decree to calculate safety distances following a Fire Safety Engineering approach a method is proposed for calculation of safety distances. The present paper presents the Italian regulation and describes an approach to calculate the safety distances including an example applied on the dispenser.

Hydrogen is a crucial raw materials to other industries. Globally nearly 90% of the hydrogen or HyCO gas produced is consumed by the ammonia methanol and oil refining industries. In the future hydrogen could play an important role in the decarbonisation of transport fuel (i.e. use of fuel cell vehicles) and space heating (i.e. industrial commercial building and residential heating). This paper summarizes the results of the feasibility study carried out by Amec Foster Wheeler for the IEA Greenhouse Gas R&D Programme (IEA GHG) with the purpose of evaluating the performance and costs of a modern steam methane reforming without and with CCS producing 100000 Nm3 /h H2 and operating as a merchant plant. This study focuses on the economic evaluation of five different alternatives to capture CO2 from SMR. This paper provides an up-to-date assessment of the performance and cost of producing hydrogen without and with CCS based on technologies that could be erected today. This study demonstrates that CO2 could be captured from an SMR plant with an overall capture rate ranging between 53 to 90%. The integration of CO2 capture plant could increase the NG consumption by -0.03 to 1.41 GJ per Nm3 /h of H2. The amount of electricity exported to the grid by the SMR plant is reduced. The levelised cost of H2 production could increase by 2.1 to 5.1 € cent per Nm3 H2 (depending on capture rate and technology selected). This translates to a CO2 avoidance cost of 47 to 70 €/t.

The decarbonisation of waterborne transport is arguably the biggest challenge faced by the maritime industry presently. By 2050 the International Maritime Organization (IMO) aims to reduce greenhouse gas emissions from the shipping industry by 50% compared to 2008 with a vision to phase out fossil fuels by the end of the century as a matter of urgency. To meet such targets action must be taken immediately to address the barriers to adopt the various clean shipping options currently at different technological maturity levels. Green hydrogen as an alternative fuel presents an attractive solution to meet future targets from international bodies and is seen as a viable contributor within a future clean shipping vision. The cost of hydrogen fuel—in the shortterm at least—is higher compared to conventional fuel; therefore energy-saving devices (ESDs) for ships are more important than ever as implementation of rules and regulations restrict the use of fossil fuels while promoting zero-emission technology. However existing and emerging ESDs in standalone/combination for traditional fossil fuel driven vessels have not been researched to assess their compatibility for hydrogen-powered ships which present new challenges and considerations within their design and operation. Therefore this review aims to bridge that gap by firstly identifying the new challenges that a hydrogen-powered propulsion system brings forth and then reviewing the quantitative energy saving capability and qualitive additional benefits of individual existing and emerging ESDs in standalone and combination with recommendations for the most applicable ESD combinations with hydrogen-powered waterborne transport presented to maximise energy saving and minimise the negative impact on the propulsion system components. In summary the most compatible combination ESDs for hydrogen will depend largely on factors such as vessel types routes propulsion operation etc. However the mitigation of load fluctuations commonly encountered during a vessels operation was viewed to be a primary area of interest as it can have a negative impact on hydrogen propulsion system components such as the fuel cell; therefore the ESD combination that can maximise energy savings as well as minimise the fluctuating loads experienced would be viewed as the most compatible with hydrogen-powered waterborne transport.

Meeting the Paris Agreement's goal to limit global warming to well below 2 °C and pursuing efforts towards 1.5 °C is likely to require more rapid and fundamental energy system changes than the previously-agreed 2 °C target. Here we assess over 200 integrated assessment model scenarios which achieve 2 °C and well-below 2 °C targets drawn from the IPCC's fifth assessment report database combined with a set of 1.5 °C scenarios produced in recent years. We specifically assess differences in a range of near-term indicators describing CO2 emissions reductions pathways changes in primary energy and final energy across the economy's major sectors in addition to more detailed metrics around the use of carbon capture and storage (CCS) negative emissions low-carbon electricity and hydrogen.

Green hydrogen will be an essential part of the future 100% sustainable energy and industry system. Up to one-third of the required solar and wind electricity would eventually be used for water electrolysis to produce hydrogen increasing the cumulative electrolyzer capacity to about 17 TWel by 2050. The key method applied in this research is a learning curve approach for the key technologies i.e. solar photovoltaics (PV) and water electrolyzers and levelized cost of hydrogen (LCOH). Sensitivities for the hydrogen demand and various input parameters are considered. Electrolyzer capital expenditure (CAPEX) for a large utility-scale system is expected to decrease from the current 400 €/kWel to 240 €/kWel by 2030 and to 80 €/kWel by 2050. With the continuing solar PV cost decrease this will lead to an LCOH decrease from the current 31–81 €/ MWhH2LHV (1.0–2.7 €/kgH2) to 20–54 €/MWhH2LHV (0.7–1.8 €/kgH2) by 2030 and 10–27 €/MWhH2LHV (0.3–0.9 €/kgH2) by 2050 depending on the location. The share of PV electricity cost in the LCOH will increase from the current 63% to 74% by 2050.