Publications

This article presents a 3D model of a yellow hydrogen generation system that uses the electricity produced by a photovoltaic carport. The 3D models of all key system components were collected and their characteristics were described. Based on the design of the 3D model of the photovoltaic carport the amount of energy produced monthly was determined. These quantities were then applied to determine the production of low-emission hydrogen. In order to increase the amount of low-emission hydrogen produced the usage of a stationary energy storage facility was proposed. The Metalog family of probability distributions was adopted to develop a strategic model for low-emission hydrogen production. The hydrogen economy of a company that uses small amounts of hydrogen can be based on such a model. The 3D modeling and calculations show that it is possible to design a compact low-emission hydrogen generation system using rapid prototyping tools including the photovoltaic carport with an electrolyzer placed in the container and an energy storage facility. This is an effective solution for the climate and energy transition of companies with low hydrogen demand. In the analytical part the Metalog probability distribution family was employed to determine the amount of monthly energy produced by 6.3 kWp photovoltaic systems located in two European countries: Poland and Italy. Calculating the probability of producing specific amounts of hydrogen in two European countries is an answer to a frequently asked question: In which European countries will the production of low-emission hydrogen from photovoltaic systems be the most profitable? As a result of the calculations for the analyzed year 2023 in Poland and Italy specific answers were obtained regarding the probability of monthly energy generation and monthly hydrogen production. Many companies from Poland and Italy are taking part in the European competition to create hydrogen banks. Only those that offer low-emission hydrogen at the lowest prices will receive EU funding.

With the adjustment of energy structure the utilization of hydrogen energy has been widely attended. China’s carbon neutrality targets make it urgent to change traditional coal-fired power generation. The paper investigates the combustion of pulverized coal blended with hydrogen to reduce carbon emissions. In terms of calorific value the pulverized coal combustion with hydrogen at 1% 5% and 10% blending ratios is investigated. The results show that there is a significant reduction in CO2 concentration after hydrogen blending. The CO2 concentration (mole fraction) decreased from 15.6% to 13.6% for the 10% hydrogen blending condition compared to the non-hydrogen blending condition. The rapid combustion of hydrogen produces large amounts of heat in a short period which helps the ignition of pulverized coal. However as the proportion of hydrogen blending increases the production of large amounts of H2O gives an overall lower temperature. On the other hand the temperature distribution is more uniform. The concentrations of O2 and CO in the upper part of the furnace increased. The current air distribution pattern cannot satisfy the adequate combustion of the fuel after hydrogen blending.

This work investigated hydrogen production from biomass feedstocks (i.e. glucose starch lignin and cellulose) using a 100 mL h-type proton exchange membrane electrolysis cell. Biomass electrolysis is a promising process for hydrogen production although low in technology readiness level but with a series of recognised advantages: (i) lower-temperature conditions (compared to thermochemical processes) (ii) minimal energy consumption and low-cost post-production (iii) potential to synthesise high-volume H2 and (iv) smaller carbon footprint compared to thermochemical processes. A Lewis acid (FeCl3 ) was employed as a charge carrier and redox medium to aid in the depolymerisation/oxidation of biomass components. A comprehensive analysis was conducted measuring the H2 and CO2 emission volume and performing electrochemical analysis (i.e. linear sweep voltammetry and chronoamperometry) to better understand the process. For the first time the influence of temperature on current density and H2 evolution was studied at temperatures ranging from ambient temperature (i.e. 19 ◦C) to 80 ◦C. The highest H2 volume was 12.1 mL which was produced by FeCl3 -mediated electrolysis of glucose at ambient temperature which was up to two times higher than starch lignin and cellulose at 1.20 V. Of the substrates examined glucose also showed a maximum power-to-H2 -yield ratio of 30.99 kWh/kg. The results showed that hydrogen can be produced from biomass feedstock at ambient temperature when a Lewis acid (FeCl3 ) is employed and with a higher yield rate and a lower electricity consumption compared to water electrolysis.

Transition to a sustainable energy supply is essential for addressing the challenges of climate change and achieving a low-carbon future. Green hydrogen produced from solar photovoltaic (PV) systems presents a promising solution in Ghana where energy demands are increasing rapidly. The levelized cost of hydrogen (LCOH) is considered a critical metric to evaluate hydrogen production techniques cost competitiveness and economic viability. This study presents a comprehensive analysis of LCOH from solar PV systems. The study considered a 5 MW green hydrogen production plant in Ghana’s capital Accra as a proposed system. The results indicate that the LCOH is about $9.49/kg which is comparable to other findings obtained within the SubSaharan Africa region. The study also forecasted that the LCOH for solar PV-based hydrogen produced will decrease to $5–6.5/kg by 2030 and $2–2.5/kg by 2050 or lower making it competitive with fossil fuel-based hydrogen. The findings of this study highlight the potential of green hydrogen as a sustainable energy solution and its role in driving the country’s net-zero emissions agenda in relation to its energy transition targets. The study’s outcomes are relevant to policymakers researchers investors and energy stakeholders in making informed decisions regarding deploying decentralised green hydrogen technologies in Ghana and similar contexts worldwide.

The need to reduce the carbon footprint of conventional energy sources has made green hydrogen a promising solution for the energy transition. The most environmentally friendly way to produce hydrogen is through water-based production using renewable energy. However the availability of fresh water is limited so switching to wastewater instead of fresh water is the key solution to this problem. In response to this issue the present review reports the main findings of the research studies dealing with the feasibility of hydrogen production from wastewater using various technologies including biological electrochemical and advanced oxidation routes. These methods have been studied in a large number of experiments with the aim of investigating and improving the potential of each method. On the other hand the maturity of solar energy technologies has led researchers to focus on the possibility of harnessing this source and combining it with wastewater treatment techniques for the production of green hydrogen. Therefore the present review pays special attention to solar driven hydrogen production from wastewater by highlighting the potential of several technologies for simultaneous water treatment and green hydrogen production from wastewater. Recent results limitations challenges possible improvements and techno-economic assessments reported by several authors as well as future directions of research and industrial implementation in this field are reported.

Currently there is a growing interest in increasing the power range of air-cooled fuel cells (ACFCs) as they are cheaper easier to use and maintain than water-cooled fuel cells (WCFCs). However air-cooled stacks are only available up to medium power (<10 kW). Therefore a good solution may be the development of ACFCs consisting of several stacks until the required power output is reached. This is the concept of air-cooled multi-stack fuel cell (AC-MSFC). The objective of this work is to develop a turnkey solution for the integration of AC-MSFCs in renewable microgrids specifically those with high-voltage DC (HVDC) bus. This is challenging because the AC-MSFCs must operate in the microgrid as a single ACFC with adjustable power depending on the number of stacks in operation. To achieve this the necessary power converter (ACFCs operate at low voltages so high conversion rates are required) and control loops must be developed. Unlike most designs in the literature the proposed solution is compact forming a system (AC-MSFCS) with a single input (hydrogen) and a single output (high voltage regulated power or voltage) that can be easily integrated into any microgrid and easily scalable depending on the power required. The developed AC-MSFCS integrates stacks balance of plant data acquisition and instrumentation power converters and local controllers. In addition a virtual instrument (VI)has been developed which connected to the energy management system (EMS) of the microgrid allows monitoring of the entire AC-MSFCS (operating temperature purging cell voltage monitoring for degradation evaluation stacks operating point control and alarm and event management) as well as serving as a user interface. This allows the EMS to know the degradation of each stack and to carry out energy distribution strategies or specific maintenance actions which improves efficiency lifespan and of course saves costs. The experimental results have been excellent in terms of the correct operation of the developed AC-MSFCS. Likewise the accumulated degradation of the stacks was quantified showing cells with a degradation of >80%. The excellent electrical and thermal performance of the developed power converter was also validated which allowed the correct and efficient supply of regulated power (average efficiency above 90%) to the HVDC bus according to the power setpoint defined by the EMS of the microgrid.

Legislation regulating the sustainability requirements for hydrogen technologies relies more and more on life cycle assessments (LCAs). Due to different scopes and development processes different pieces of EU legislation refer to different LCA methodologies with differences in the way multifunctional processes (i.e. co-productions recycling and energy recovery) are treated. These inconsistencies arise because incentive mechanisms are not standardized across sectors even though the end product hydrogen remains the same. The goal of this paper is to compare the life-cycle greenhouse gas (GHG) emissions of hydrogen from four production pathways depending on the multifunctional approach prescribed by the different EU policies (e.g. using substitution or allocation). The study reveals a large variation in the LCA results. For instance the life-cycle GHG emissions of hydrogen co-produced with methanol is found to vary from 1 kg CO2-equivalent/kg H2 (when mass allocation is considered) to 11 kg CO2-equivalent/kg H2 (when economic allocation is used). These inconsistencies could affect the market (e.g. hydrogen from a certain pathway could be considered sustainable or unsustainable depending on the approach) and the environment (e.g. pathways that do not lead to a global emission reduction could be promoted). To mitigate these potential negative effects we urge for harmonized and strict guidelines to assess the life-cycle GHG emissions of hydrogen technologies in an EU policy context. Harmonization should cover international policies too to avoid the same risks when hydrogen will be traded based on its GHG emissions. The appropriate methodological approach for each production pathway should be chosen by policymakers in collaboration with the LCA community and stakeholders from the industry based on the potential market and environmental consequences of such choice.

Following the introduction of the EU’s Hydrogen Strategy in 2020 as part of the European Green Deal some EU member states have deployed a very active hydrogen diplomacy. Germany The Netherlands and Belgium have been the most active ones establishing no less than 40 bilateral hydrogen trade partnerships with 30 potential export countries in the last three years. However concerns have been voiced about whether such hydrogen trade relationships can be economically feasible geopolitically wise environmentally sustainable and socially just. This article therefore evaluates these partnerships considering three risk dimensions: economic political and sustainability (covering both environmental and justice) risks. The analysis reveals that the selection of partner countries entails significant trade-offs. Four groups of partner countries can be identified based on their respective risk profile: “Last Resorts” “Volatile Ventures” “Strategic Gambits” and “Trusted Friends”. Strikingly less than one-third of the agreements are concluded with countries that fall within the “Trusted Friends” category which have the lowest overall risk profile. These findings show the need for policy makers to think much more strategically about which partnerships to pursue and to confront tough choices about which risks and trade-offs they are willing to accept.

Proton Exchange Membrane (PEM) electrolysis an advanced technique for producing hydrogen with efficiency and environmental friendliness signifies the forefront of progress in this domain. Compared to alkaline cells these electrolytic cells offer numerous advantages such as lower operating temperatures enhanced hydrogen production efficiency and eliminating the need for an aqueous solution. However PEM electrolysis still faces limitations due to the high cost of materials used for the membrane and catalysts resulting in elevated expenses for implementing large-scale systems. The pivotal factor in improving PEM electrolysis lies in the Platinum catalyst present on the membrane surface. Enhancing catalytic efficiency through various methods and advancements holds immense significance for the progress of this technology. This study investigates the use of patterned membranes to improve the performance of PEM electrolytic cells toward green hydrogen production. By increasing the Platinum loading across the membrane surface and enhancing catalytic performance these patterned membranes overcome challenges faced by conventionally fabricated counterparts. The findings of this research indicate that membranes with modified surfaces not only exhibit higher current draw but also achieve elevated rates of hydrogen production.

Hydrogen is a promising energy carrier for a low-carbon future energy system as it can be stored on a megaton scale (equivalent to TWh of energy) in subsurface reservoirs. However safe and efficient underground hydrogen storage requires a thorough understanding of the geomechanics of the host rock under fluid pressure fluctuations. In this context we summarize the current state of knowledge regarding geomechanics relevant to carbon dioxide and natural gas storage in salt caverns and depleted reservoirs. We further elaborate on how this knowledge can be applied to underground hydrogen storage. The primary focus lies on the mechanical response of rocks under cyclic hydrogen injection and production fault reactivation the impact of hydrogen on rock properties and other associated risks and challenges. In addition we discuss wellbore integrity from the perspective of underground hydrogen storage. The paper provides insights into the history of energy storage laboratory scale experiments and analytical and simulation studies at the field scale. We also emphasize the current knowledge gaps and the necessity to enhance our understanding of the geomechanical aspects of hydrogen storage. This involves developing predictive models coupled with laboratory scale and field-scale testing along with benchmarking methodologies.