Publications

Concerns about the competitiveness of European industry led to the publication of the Draghi report. One of his recommendations is to install regional green industrial clusters around energy-intensive companies. The report identifies three benefit categories each corresponding to typical industrial symbiosis cases: improved investment cases by shared local low-carbon energy generation improved investment cases by shared infrastructure and improved energy flows for increased resource efficiency. Industrial clusters hold untapped potential to advance the energy transition and climate neutrality. However it is still unknown how and if this potential will ever be reached nor how scalable and replicable the benefits will be. This review paper aims to take a first step in exploring the potential role of industrial clusters in the energy system by exposing the research state of the art in academic literature. A literature review is performed in line with the three benefit categories according to Draghi to understand the enablers and barriers of potential synergies and their impact on the energy system. Afterwards the scalability is assessed by positioning the European industrial clusters in the larger renewable energy landscape. To illustrate the global interest a brief reflection is made on references to industrial clusters in the policy of non-European regions. The work concludes with interesting leads for future research to further advance knowledge on the importance of industrial clusters in the energy system and to stimulate the implementation of energy synergies.

This paper investigates the performance and economic viability of Combined Cycle Gas Turbines (CCGT) operating on natural gas (NG) and hydrogen within the context of evolving electricity markets. The study is structured into several sections beginning with a benchmark analysis to establish baseline performance metrics including break-even prices and price margins for CCGTs running on NG. The research then explores various base cases and sensitivity analyses focusing on different CCGT capacity factors and the uncertainties surrounding key parameters. The study also compares the performance of CCGTs across different European countries highlighting the impact of increased price fluctuations in forecasted electricity markets. Additionally the paper examines Power-to-X-to-Power (P2X2P) configurations assessing the economic feasibility of hydrogen production and its integration into CCGT operations. The analysis considers scenarios where hydrogen is sourced externally or produced on-site using renewable energy or grid electricity during off-peak hours. The results provide insights into the competitiveness and adaptability of CCGTs in a transitioning energy landscape emphasizing the potential role of hydrogen as a flexible and sustainable energy carrier.

This study presents a comprehensive framework that integrates high-resolution energy forecasting and technoeconomic modeling to assess green hydrogen production potential in Flanders Belgium. Using 15-min interval data from the Elia Group four deep learning models (LSTM BiLSTM GRU and CNN-LSTM) were developed to forecast regional photovoltaic (PV) and onshore wind energy generation. These forecasts informed the estimation of hydrogen yields and the evaluation of the levelized cost of hydrogen (LCOH) under different configurations. Results show that wind-powered hydrogen production achieves the lowest LCOH (6.63 €/kg) due to higher annual operating hours. Among electrolysis technologies alkaline electrolysis (AEL) offers the lowest cost while proton exchange membrane (PEMEL) provides greater flexibility for intermittent power sources. The hybrid PVwind system demonstrated seasonal complementarity increasing annual hydrogen yield and improving production stability. The proposed framework supports regional planning and highlights strategic investment opportunities for cost-effective green hydrogen deployment.

A potential strategy to promote the use of clean energy is the development of catalyst-coated cathodic electrodes that are economical effective and sustainable to enhance the generation of hydrogen (H2) through the electrolysis process. This study investigates the unique design and use of stainless steel (SS) coated with a CuNiZnFeOx catalyst as both anode and cathode electrodes in the alkaline electrolysis process. The electrode exhibits an improved electrochemical behavior achieving a current density of 92 mA/cm2 at an applied voltage of 2.5 V with a surface area of 36 cm2 in 1 M KOH electrolyte at 25 ◦C. Furthermore the H2 production is systematically investigated by varying electrolyte concentration applied voltage and temperature. The results demonstrate that H2 production increases significantly with enhanced electrolyte concentration (3102 mL at 2 M KOH) applied voltage (3468 mL at 3.0 V) and temperature (3202 mL at 60 ◦C) over a 300 min electrolysis time. However optimal operating conditions are determined to be 1 M KOH 2.5 V and 25 ◦C balancing performance and energy efficiency. The improved performance is primarily attributed to enhanced ionic conductivity reduced internal resistance and the synergistic catalytic activity of the Cu-integrated NiZnFeOx coating.

Hydrogen plays a central role in ensuring the fulfillment of the climate and energy goals established in the Paris Agreement. To implement sustainable and resilient hydrogen economies it is essential to analyze the entire hydrogen value chain following a Life Cycle Assessment (LCA) methodology. To determine the current methodologies approaches and research tendencies adopted when performing LCA of hydrogen energy systems a systematic literature analysis is carried out in the present study. The choices regarding the “goal and scope definition” “life cycle inventory analysis” and “life cycle impact assessment” in 70 scientific papers were assessed. Based on the collected information it was concluded that there are no similar LCA studies since specificities introduced in the system boundaries functional unit production storage transportation end-use technologies geographical specifications and LCA methodological approaches among others introduce differences among studies. This lack of harmonization triggers the need to define harmonization protocols that allow for a fair comparison between studies; otherwise the decision-making process in the hydrogen energy sector may be influenced by methodological choices. Although initial efforts have been made their adoption remains limited and greater promotion is needed to encourage wider implementation.

The growing demand for air connectivity coupled with the forecasted increase in passengers by 2040 implies an exigency in the aviation sector to adopt sustainable approaches for net zero emission by 2050. Sustainable Aviation Fuel (SAF) is currently the most promising short-term solution; however ensuring its overall sustainability depends on reducing the life cycle carbon footprints. A key challenge prevails in hydrogen usage as a reactant for the approved ASTM routes of SAF. The processing conversion and refinement of feed entailing hydrodeoxygenation (HDO) decarboxylation hydrogenation isomerisation and hydrocracking requires substantial hydrogen input. This hydrogen is sourced either in situ or ex situ with the supply chain encompassing renewables or non-renewables origins. Addressing this hydrogen usage and recognising the emission implications thereof has therefore become a novel research priority. Aside from the preferred adoption of renewable water electrolysis to generate hydrogen other promising pathways encompass hydrothermal gasification biomass gasification (with or without carbon capture) and biomethane with steam methane reforming (with or without carbon capture) owing to the lower greenhouse emissions the convincing status of the technology readiness level and the lower acidification potential. Equally imperative are measures for reducing hydrogen demand in SAF pathways. Strategies involve identifying the appropriate catalyst (monometallic and bimetallic sulphide catalyst) increasing the catalyst life in the deoxygenation process deploying low-cost iso-propanol (hydrogen donor) developing the aerobic fermentation of sugar to 14 dimethyl cyclooctane with the intermediate formation of isoprene and advancing aqueous phase reforming or single-stage hydro processing. Other supportive alternatives include implementing the catalytic and co-pyrolysis of waste oil with solid feedstocks and selecting highly saturated feedstock. Thus future progress demands coordinated innovation and research endeavours to bolster the seamless integration of the cutting-edge hydrogen production processes with the SAF infrastructure. Rigorous technoeconomic and life cycle assessments alongside technological breakthroughs and biomass characterisation are indispensable for ensuring scalability and sustainability

This work develops a replicable method for designing the optimal renewable hydrogen production facility applicable to any site and based on technical parameters and actual equipment costs. The solution is based on the integration of photovoltaic (PV) energy with lithium-ion battery storage systems which maximizes electrolyzer operating hours and significantly reduces the Levelized Cost of Hydrogen (LCOH). This study shows that increasing the inclination of the photovoltaic modules reduces the need for storage optimizing operation and extending the electrolyzer’s annual operating hours. In the Seville case study with current costs and efficiencies a minimum LCOH of €4.43/kg was achieved a value well below market benchmarks opening the door to a potentially competitive industrial business. The analysis confirms that electrolyzer efficiency—particularly specific power consumption—is the most important factor in reducing costs while technological progress in photovoltaics storage and equipment promises further reductions in the coming years. Overall the proposed methodology offers a practical and scalable tool to accelerate the economic viability of green hydrogen in a variety of contexts.

The increasing global demand for clean energy highlights hydrogen as a strategic energy carrier due to its high energy density and carbon-free utilization. Currently steam methane reforming (SMR) is the most widely applied method for hydrogen production; however its high CO2 emissions undermine the environmental benefits of hydrogen. Blue hydrogen production integrates carbon capture and storage (CCS) technologies to overcome this drawback in the SMR process significantly reducing greenhouse gas emissions. This study integrated a MATLAB-R2025b-based plug flow reactor (PFR) model for SMR kinetics with an Aspen HYSYS-based CCS system. The effects of reformer temperature (600–1000 ◦C) and steam-to-carbon (S/C) ratio (1–5) on hydrogen yield and CO2 emission intensity were investigated. Results show that hydrogen production increases with temperature reaching maximum conversion at 850–1000 ◦C while the optimum performance is achieved at S/C ratios of 2.5–3.0 balancing high hydrogen yield and minimized methane slip. Conventional SMR generates 9–12 kgCO2/kgH2 emissions whereas SMR + CCS reduces this to 2–3 kgCO2/kgH2 achieving more than 75% reduction. The findings demonstrate that SMR + CCS integration effectively mitigates emissions and provides a sustainable bridging technology for blue hydrogen production supporting the transition toward lowcarbon energy systems.

The paper studies and analyzes electric vehicle engines powered by hydrogen under the WLTP standard driving protocol. The driving range extension is estimated using a specific protocol developed for FCEV compared with the standard value for battery electric vehicles. The driving range is extended by 10 km averaging over the four protocols with a maximum of 11.6 km for the FTP-75 and a minimum of 7.7 km for the WLTP. This driving range extension represents a 1.8% driving range improvement on average. Applying the FCEV current weight the driving range is extended to 18.9 km and 20.4 km on average when using power source energy capacity standards for BEVs and FCEVs.

Blue hydrogen technology generated from natural gas through carbon capture and storage (CCS) technology is a promising solution to mitigate greenhouse gas emissions and meet the growing demand for clean energy. To improve the sustainability of blue hydrogen it is crucial to explore alternative feedstocks production methods and improve the efficiency and economics of carbon capture storage and utilization strategies. Two established technologies for hydrogen synthesis are Steam Methane Reforming (SMR) and Autothermal Reforming (ATR). The choice between SMR and ATR depends on project specifics including the infrastructure energy availability environmental goals and economic considerations. ATR-based facilities typically generate hydrogen at a lower cost than SMR-based facilities except in cases where electricity prices are elevated or the facility has reduced capacity. Both SMR and ATR are methods used for hydrogen production from methane but ATR offers an advantage in minimizing CO2 emissions per unit of hydrogen generated due to its enhanced energy efficiency and unique process characteristics. ATR provides enhanced utility and flexibility regarding energy sources due to its autothermal characteristics potentially facilitating integration with renewable energy sources. However SMR is easier to run but may lack flexibility compared to ATR necessitating meticulous management. Capital expenditures for SMR and ATR hydrogen reactors are similar at the lower end of the capacity spectrum but when plant capacity exceeds this threshold the capital costs of SMR-based hydrogen production surpass those of ATR-based facilities. The less profitably scaled-up SMR relative to the ATR reactor contributes to the cost disparity. Additionally individual train capacity constraints for SMR CO2 removal units and PSA units increase the expenses of the SMR-based hydrogen facility significantly.