Publications

The deployment of large installed power capacities from intermittent renewable energy sources requires balancing to ensure the steady and safe operation of the electrical grid. New methods of energy storage are essential to store excess electrical power when energy is not needed and later use it during high-demand periods both in the short and long term. Power-to-Gas (P2G) is an energy storage solution that uses electric power produced from renewables to generate gas fuels such as hydrogen which can be stored for later use. Hydrogen produced in this manner can be utilized in energy storage systems and in transportation as fuel for cars trams trains or buses. Currently most hydrogen is produced from fossil fuels. Solid-oxide electrolysis (SOE) offers a method to produce clean hydrogen without harmful emissions being the most efficient of all electrolysis methods. The objective of this work is to determine the optimal operational parameters of an SOE system such as lower heating value (LHV)-based efficiency and total input power based on calculations from a mathematical model. The results are provided for three different operating temperature levels and four different steam utilization ratios. The introductory chapter outlines the motivation and background of this work. The second chapter explains the basics of electrolysis and describes its different types. The third chapter focuses on solid-oxide electrolysis and electrolyzer systems. The fourth chapter details the methodology including the mathematical formulations and software used for simulations. The fifth chapter presents the results of the calculations with conclusions. The final chapter summarizes this work.

Sweden with its abundant access to low-cost fossil-free electricity is well-positioned to become a significant hydrogen exporter. This study presents a techno-economic analysis of different hydrogen carriers—compressed hydrogen methanol ammonia and liquid organic hydrogen carriers (LOHC)—for export applications. Using the Northern Green Crane Project as a reference for scale the analysis focuses on cost optimization for hydrogen production storage and transportation. A linear programming model is developed to optimize capacities and operational strategies for each carrier ensuring a fair basis for comparison. Results indicate that LOHC and ammonia are competitive with compressed hydrogen showing particular promise for larger-scale long-distance deliveries. These findings offer valuable insights for policymakers and industry stakeholders developing Sweden’s hydrogen export strategies.

The production of green hydrogen the cleanest energy source plays a crucial role in enhancing the efficiency of renewable energy systems by utilizing surplus energy that would otherwise be wasted. With the global shift towards sustainability and the rising adoption of renewable energy sources green hydrogen is gaining significant importance as both an energy carrier and a storage solution. However determining the optimal locations for green hydrogen production facilities remains a complex challenge due to the interplay of technical economic logistical and environmental factors. This study introduces the City Location Evaluation Optimization for Green Hydrogen (CELO_GH) algorithm a novel heuristic approach designed to address this challenge. Unlike conventional multi-criteria decision-making (MCDM) models CELO_GH dynamically evaluates cities by considering renewable energy surplus proximity to industrial hydrogen demand port and pipeline accessibility and economic viability. A case study conducted in Turkey demonstrates the effectiveness of the approach by identifying optimal cities for green hydrogen production based on real-world energy and infrastructure data. The problem was also solved with the genetic algorithm and the results were compared and it was seen that the proposed heuristic provides the lowest cost location selection. A geographically flexible methodology as the proposed algorithm can be applied globally to regions with high renewable energy potential ensuring scalability and adaptability for future energy transition strategies. The results provide valuable insights for policy-makers energy investors and industrial planners aiming to optimize green hydrogen infrastructure while ensuring cost efficiency and sustainability.

The increasing global demand for clean energy and sustainable industrial processes necessitates innovative approaches to energy production and chemical synthesis. This study proposed and simulated an innovative integrated system for the co-production of power hydrogen and dimethyl ether (DME) combining the high-efficiency Allam– Fetvedt cycle with co-electrolysis and indirect DME synthesis. The Allam–Fetvedt cycle generated electricity while capturing CO2 which along with water was used in solid oxide electrolyzers (SOEs) to produce syngas via co-electrolysis. The resulting syngas was converted to methanol and subsequently to DME. Aspen HYSYS was used to model and simulate the process and heat/mass integration strategies were implemented to reduce energy demand and optimize resource utilization. The proposed integrated process enabled an annual production of 980021 metric tons of DME 189435 metric tons of hydrogen and 7698.27 metric tons of methanol. The energy efficiency of the Allam–Fetvedt cycle reached 55% and heat integration reduced the system’s net energy demand by 14.22%. Despite the high energy needs of the electrolyzer system (81.28% of net energy) the overall energy requirement remained competitive with conventional methods. Carbon emissions per kilogram of DME were reduced from 1.16 to 0.77 kg CO2 through heat integration and can be further minimized to 0.0308 kg CO2/kg DME (near zero) with renewable electrification. Results demonstrated that 96% of CO2 was recycled within the Allam–Fetvedt cycle and the rest (the 4% of CO2) was captured and converted to syngas achieving net-zero carbon emissions. This work presents a scalable and sustainable pathway for integrated clean energy and chemical production advancing toward industrial net-zero targets.

Hydrogen (H2) production from biomass has emerged as a promising alternative to fossil-based pathways addressing the global demand for low-carbon energy solutions. This study compares the environmental impacts of two biomass-based H2 production processes biogas reforming and agricultural residue gasification through a life cycle assessment (LCA). Using real-world data from the literature the analysis considered key system boundaries for each process including biogas production reforming and infrastructure for the former and biomass cultivation syngas generation and offgas management for the latter. Environmental impacts were evaluated using SimaPro software (Version 9.4) and the ReCiPe midpoint (H) method. The results revealed that biogas reforming emits approximately 5.047 kg CO2-eq per kg of H2 which is 4.89 times higher than the emissions from agricultural residue gasification (1.30 kg CO2-eq/kg H2) demonstrating the latter’s superior environmental performance. Gasification consumes fewer fossil resources (3.20 vs. 10.42 kg oil-eq) and poses significantly lower risks to human health (1.51 vs. 23.28 kg 14-DCB-eq). Gasification water consumption is markedly higher (5.37 compared to biogas reforming (0.041 m3/kg H2)) which is an important factor to consider for sustainability. These findings highlight gasification as a more sustainable H2 production method and emphasize its potential as an eco-friendly solution. To advance sustainability in energy systems integrating socio-economic studies with LCA is recommended alongside prioritizing agricultural residue gasification for hydrogen production.

It is essential to promote the study of non-conventional forms of electrical energy generation to create a resilient society with awareness of and the capacity for development and experimentation to face environmental conservation challenges especially from secondary education. From a mixed methodological approach this study presents workshops with hydrogen cells to strengthen educational skills and boost the interest of 44 high school students. The methodology followed five main points: carrying out a pre-evaluation to measure prior knowledge an induction related to concepts of electronics and hydrogen cells tests with a hydrogen kit the presentation of final projects post-evaluation of knowledge and the application of a survey of motivation. Observation experimentation analysis and dissemination of results helped strengthen students’ theoretical practical and scientific knowledge. These activities awakened their interest in this type of technology as evidenced in the results of the evaluations surveys and project quality. This demonstrates the validity of hydrogen cell workshops as a valuable technique to enhance learning and motivate students to study unconventional forms of electrical energy generation.

This review paper presents an overview of fuel cell electrochemical systems that can be used for clean large-scale power generation and energy storage as global energy concerns regarding emissions and greenhouse gases escalate. The fundamental thermochemical and operational principles of fuel cell power generation and electrolyzer technologies are discussed with a focus on high-temperature solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) that are best suited for grid scale energy generation. SOFCs and SOECs share similar promising characteristics and have the potential to revolutionize energy conversion and storage due to improved energy efficiency and reduced carbon emissions. Electrochemical and thermodynamic foundations are presented while exploring energy conversion mechanisms electric parameters and efficiency in comparison with conventional power generation systems. Methods of converting hydrocarbon fuels to chemicals that can serve as fuel cell fuels are also presented. Key fuel cell challenges are also discussed including degradation thermal cycling and long-term stability. The latest advancements including in materials selection research design and manufacturing methods are also presented as they are essential for unlocking the full potential of these technologies and achieving a sustainable near zero-emission energy future.

This paper presents a comprehensive thermo-economic analysis of a novel Power-to-X (P2X) polygeneration system designed for the production of hydrogen ammonia and methanol with near-zero CO2 emissions. The system integrates an air separation unit (ASU) a direct oxy-combustor (DOC) powered by natural gas combined with a supercritical carbon dioxide (sCO2) power cycle water electrolyzer (WE) a Haber-Bosch process (HBP) and a methanol production unit (MPU). The system is investigated in four configurations: ASU + DOC-sCO2 (S1) ASU + DOC-sCO2 + WE (S2) ASU + DOC-sCO2 + WE + HBP (S3) and ASU + DOC-sCO2 + WE + HBP + MPU (S4) each contributing to improve energy efficiency and reduced emissions. Simulation results show that the overall system efficiency reaches 56 % improving from 45 % to 56 % across different configurations. The system’s levelized cost of hydrogen (LCOH) decreases significantly from $1.70/kg to $0.80/kg and the levelized cost of electricity (LCOE) decreases from 4.30 ¢/kWh to 3.30 ¢/kWh. CO2 emissions are reduced from 200 gCO2/ MWe to 145 gCO2/MWe with the CO2 reduction rate improving from 89 % to 94 %. These results demonstrate the economic viability and environmental sustainability of the proposed P2X system paving the way for industrial decarbonization and large-scale deployment in future energy infrastructures.

Hydrogen has become an important component of the global transition to zero-carbon economies. Low-carbon and green hydrogen gas and fuel cell technology for domestic household use will depend on skilled practi tioners particularly gasfitters to convert install and maintain hydrogen-based appliances. Upskilling gasfitters to work with hydrogen is critical to transitioning from natural gas to hydrogen for heating and cooking. Yet limited research exists on training and upskilling trade practitioners in the context of renewable energy and lowcarbon technologies. This paper makes a novel contribution to research on upskilling for renewable and lowcarbon technologies by drawing on the findings from a survey of 1001 plumbers in Australia. The survey designed using the Theory of Planned Behavior aimed to predict behaviors regarding hydrogen training and ascertain social and structural enablers for such behavior. The results show that plumbers have limited awareness of hydrogen yet have positive attitudes towards upskilling to work with the low-carbon fuel. Perceived benefits to business sustainability customer service and safety underpin the positive attitudes. The research shows that while plumbers are enthusiastic about upskilling for hydrogen upskilling policies and programs must ensure key stakeholders who inform plumbers’ ongoing practice are on board and informed about hydrogen training opportunities.

Materials-based H2 storage plays a critical role infacilitating H2 as a low-carbon energy carrier but there remainslimited guidance on the technical performance necessary for specificapplications. Metal−organic framework (MOF) adsorbents haveshown potential in power applications but need to demonstrateeconomic promises against incumbent compressed H2 storage.Herein we evaluate the potential impact of material propertiescharge/discharge patterns and propose targets for MOFs’ deploy-ment in long-duration energy storage applications including backupload optimization and hybrid power. We find that state-of-the-artMOF could outperform cryogenic storage and 350 bar compressedstorage in applications requiring ≤8 cycles per year but need ≥5 g/Lincrease in uptake to be cost-competitive for applications thatrequire ≥30 cycles per year. Existing challenges include manufacturing at scale and quantifying the economic value of lower-pressure storage. Lastly future research needs are identified including integrating thermodynamic effects and degradation mechanisms.