Production & Supply Chain

This study comprehensively analyzes an integrated renewable energy system complementing offshore wind turbines (OWT) and floating solar photovoltaic (FPV) technology designed for producing electric power and green hydrogen. The research explores the technical feasibility techno-economic performance and optimal sizing of the system components. The system integrates OWT farms FPV arrays water electrolyzer and hydrogen storage tank to minimize the levelized cost of energy (LCOE) loss of power supply probability (LPSP) and excess energy. A novel optimization approach Dung Beetle Optimization (DBO) algorithm is utilized and compared with the Grey Wolf Optimizer (GWO) for performance validation. To ensure the robustness of the proposed DBO algorithm it is thoroughly tested on two system configurations: a standalone OWT hydrogen production system and a hybrid FPV/OWT hydrogen production system. The results showed that the DBO algorithm outperforms the GWO algorithm in terms of system efficiency cost-effectiveness and reliability. The optimization findings reveal that the FPV/OWT hybrid system optimized with the DBO algorithm leads to a more cost-effective configuration with the OWT component contributing 45.96% of the total costs. Moreover the optimized FPV/OWT system achieves a lower levelized cost of energy (LCOE) of 0.5797 $/kWh compared to 0.8190 $/kWh for the standalone OWT system. Furthermore the hybrid FPV/OWT system maintains a levelized cost of hydrogen (COH) of 1.205 $/kg making it a competitive option for large-scale hydrogen production. Conclusively the findings demonstrate the technical feasibility and economic viability of the designated hybrid system for sustainable off-grid rural electrification and hydrogen production offering a robust solution to meet future energy demands.

Hydrogen energy as a medium for long-term energy storage needs to ensure the continuous and stable operation of the electrolyzer during the production of green hydrogen using wind energy. In this paper based on the overall model of a wind power hydrogen production system an integrated control strategy aimed at improving the quality of wind power generation smoothing the hydrogen production process and enhancing the stability of the system is proposed. The strategy combines key measures such as the maximum power point tracking control of the wind turbine and the adaptive coordinated control of the electrochemical energy storage system which can not only efficiently utilize the wind resources but also effectively ensure the stability of the bus voltage and the smoothness of the hydrogen production process. The simulation results show that the electrolyzer can operate at full power to produce hydrogen while the energy storage device is charging when wind energy is sufficient; the electrolyzer continuously produces hydrogen according to the wind energy when the wind speed is normal; and the energy storage device will take on the task of maintaining the operation of the electrolyzer when the wind speed is insufficient to ensure the stability and reliability of the system.

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.

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.

With green hydrogen gaining traction as a viable sustainable energyoption the present study explores the potential of producing greenhydrogen from wind and solar energy in Ghana. The study combinedthe use of geospatial multi-criteria approach and PEM electrolysisprocess to estimate the geographical and technical potential of theselected two renewable resources. The study also included anassessment of potential areas for grid integration. Technologyspecifications of a monocrystalline solar PV module and 1 MW windturbine module were applied. Results of the assessment show thatabout 85% of the total land area in the country is available for greenhydrogen projects. Technically capacities of ∼14196.21 Mt of greenhydrogen using solar and ∼10123.36 Mt/year from wind energy can beproduced annually in the country. It was also observed that someregions especially regions in the northern part of the country eventhough showed the most favourable locations for solar-based greenhydrogen projects with technical potential of over 1500 Mt/year theseregions may not qualify for a grid connected system based on thecurrent electrification policy of the country due to the regions’ lowpopulation density and distance from the power grid network threshold.

Hydrogen produced through natural gas reforming with carbon capture and storage (blue H2) is expected to supply up to 30 % of global low-carbon hydrogen by 2030. However wide variability in reported findings creates uncertainty about its future role. To address this the present techno-economic-environmental study from a lifecycle perspective evaluates whether blue hydrogen can meet carbon footprint thresholds (3 and 3.4 kg CO2 eq./ kg H2) required to qualify as low-carbon hydrogen. Several configurations of either chemical absorption or lowtemperature CO2 separation techniques integrated with auto-thermal reforming are modeled. Results show that low-temperature separation can achieve comparable or even superior energetic performance to conventional capture methods with cold gas and overall efficiencies reaching up to 80 % and 78 % respectively. The economic analysis estimates the levelized cost of blue hydrogen at 3.5–4 €/kg under 2024 EU average nonhousehold consumer natural gas and electricity prices and 2.4–2.8 €/kg under Italy’s 2024 wholesale prices. From an environmental standpoint life-cycle assessment indicates an average carbon footprint of 2.5 kg CO2 eq./ kg H2 assuming photovoltaic electricity for auxiliary power and excluding more carbon-intensive natural gas supply chains. The findings highlight that partial electrification of the CO2 separation unit use of renewable electricity and maximizing capture rates are key factors essential for producing compliant blue H2. Furthermore adopting ultra-low-emission natural gas supply chains could reduce blue H2′s carbon footprint to the level of green H2 suggesting that the introduction of certificate-of-origin schemes for natural gas can guarantee blue H2 with minimal emissions.

The increasing global wastewater generation and reliance on fossil fuels for energy production necessitate sustainable treatment and energy recovery solutions. This study explores supercritical water gasification (SCWG) of sewage sludge from municipal wastewater as a hydrogen production pathway focusing on the role of alkali catalysts (KOH K₂CO₃ Na₂CO₃). The effects of temperature (450–550◦C) reaction time (5–30 min) and catalyst type on gas yield and efficiency were analyzed. At 550◦C the highest carbon efficiency (61 %) gas efficiency (69 %) and hydrogen yield (41 mol/kg) were observed. After 30 min the gas composition reached H₂ (58 %) CO₂ (26 %) CH₄ (11.7 %) and CO (4 %). Among catalysts Na₂CO₃ exhibited superior H₂ yield (29 mol/kg) carbon efficiency (58 %) and gas efficiency (51 %). This study highlights SCWG as a viable technology for hydrogen-rich gas production contributing to sustainable energy solutions and wastewater valorization.

An increasing demand for energy coupled with rising pollution levels is driving the search for environmentally clean alternative energy resources to replace fossil fuels. Hydrogen has emerged as a promising clean energy carrier and raw material for various applications. However its environmental benefits depend on sustainable production methods. The rapid development of nanomaterials (NMs) has opened new avenues for the conversion and utilization of renewable energy (RE). NMs are becoming increasingly important in addressing challenges related to hydrogen (H₂) generation. This review provides an overview of current advancements in H₂ production from biomass via thermochemical (TC) and biological (BL) processes including associated costs and explores the applications of nanomaterials in these methods. Research indicates that biological hydrogen (BL-H₂) production remains costly. The challenges associated with the TC conversion process are examined along with potential strategies for improvement. Finally the technical and economic obstacles that must be overcome before hydrogen can be widely adopted as a fuel are discussed.

Green hydrogen plays a pivotal role in decarbonizing our energy system and achieving the Net-Zero Emissions goal by 2050. Offshore wind farms (OWFs) dedicated to green hydrogen production are currently recognized as the most feasible solution for scaling up the production of cost-effective electrolytic hydrogen. However the cost associated with distribution and transmission systems constitute a significant portion of the total cost in the large-scale wind-hydrogen system. This study pioneers the simultaneous optimization of the inter-array cable routing of OWFs and the location and capacity of offshore hydrogen production platforms (OHPPs) aiming to minimize the total cost of distribution and transmission systems. Considering the characteristics of hydrogen production efficiency this paper constructs a novel mathematical model for OHPPs across diverse wind scenarios. Subsequently we formulate the joint planning problem as a relaxed mixed-integer second-order cone programming (MISOCP) model and employ the Benders decomposition algorithm for the solution introducing three valid inequalities to expedite convergence. Through validation on real-world large-scale OWFs we demonstrate the validity and rapid convergence of our approach. Moreover we identify hydrogen production efficiency as a major bottleneck cost factor for the joint planning problem it decreases by 1.01% of total cost for every 1% increase in hydrogen production efficiency.

This study explores the potential of renewable seafood shell waste for sustainable energy conversion and longterm storage particularly for isolated communities. Despite its rich chitin and protein composition seafood shell waste is often neglected. The research evaluates and compares three advanced gasification technologies: biomass gasification plasma gasification and chemical looping to convert seafood shell waste into syngas and H2. The study uses validated Aspen Plus models to optimize feedstock blending ratios and operational parameters. Results show that feedstocks high in lobster and shrimp shells yield higher H2 outputs and improved syngas quality compared to clam-dominated blends. For instance biomass gasification at 1200 ◦C yielded approximately 500 kg/h of H2 from pure lobster or shrimp feeds while plasma gasification at 4500 ◦C achieved yields near 730 kg/ h. Plasma gasification when integrated with fuel cell conversion and heat recovery systems can generate over 10000 kWh during a 6-hour peak period enough to power over 1100 single-detached homes. Its levelized cost of hydrogen (LCOH) varies from $5.72-$8.37/kg H2 making it less expensive than chemical looping and biomass gasification. Plasma gasification also has the lowest global warming potential (GWP) at 6 kg CO2e/kg H2. Combining plasma gasification with carbon capture and storage may reduce GWP to 0.3 kg CO2e/kg H2 and can be further explored. These findings underscore the technical and economic viability of converting seafood shell renewable waste into H2 advancing sustainable energy transitions and supporting net-zero goals.