Applications & Pathways

While renewable energy deployment has accelerated in recent years fossil fuels continue to play a dominant role in electricity generation worldwide. This necessitates the development of transitional strategies to mitigate greenhouse gas emissions from this sector while gradually reducing reliance on fossil fuels. This study investigates the potential of blending green hydrogen with natural gas as a transitional solution to decarbonize Jordan’s electricity sector. The research presents a comprehensive techno-economic and environmental assessment evaluating the compatibility of the Arab Gas Pipeline and major power plants with hydrogen–natural gas mixtures considering blending limits energy needs environmental impacts and economic feasibility under Jordan’s 2030 energy scenario. The findings reveal that hydrogen blending between 5 and 20 percent can be technically achieved without major infrastructure modifications. The total hydrogen demand is estimated at 24.75 million kilograms per year with a reduction of 152.7 thousand tons of carbon dioxide per annum. This requires 296980 cubic meters of water per year equivalent to only 0.1 percent of the National Water Carrier’s capacity indicating a negligible impact on national water resources. Although technically and environmentally feasible the project remains economically constrained requiring a carbon price of $1835.8 per ton of carbon dioxide for economic neutrality.

The increasing penetration of renewable energy sources in power systems poses significant challenges for maintaining grid reliability mainly due to the variability and uncertainty of solar and demand profiles. Microgrids equipped with diverse storage technologies have emerged as a promising solution to address these issues.This paper proposes an integrated day-ahead and real-time power scheduling approach for grid-connected microgrids equipped with both conventional and hydrogen-based ESSs. While existing strategies often address day-ahead and real-time scheduling separately or rely on a single storage technology this work introduces a unified framework that exploits the complementary characteristics of batteries and hydrogen systems. The proposed approach is based on a novel two-stage stochastic optimization model embedded within a hierarchical optimization framework to address these two intertwined problems efficiently. For the day-ahead scheduling a two-stage stochastic programming energy management model is solved to optimize the microgrid schedule based on forecasted load demand and PV production profiles. Building upon the day-ahead schedule another optimization model is solved which addresses real-time power imbalances caused by deviations in actual PV production and load demand power profiles with respect to the forecasted ones with the aim of minimizing operational disruptions. Simulation results demonstrate the validity of the proposed approach achieving both cost reductions and minimal power imbalances. By dynamically adjusting energy flows and using both conventional batteries and hydrogen systems the proposed approach ensures improved reliability reduced operational costs and enhanced integration of RES in microgrids. These findings highlight the potential of the proposed hierarchical framework to support the large-scale deployment of RES while ensuring resilient and cost-effective microgrid operations.

Achieving net zero by 2050 will require decarbonising stand-alone energy applications. Hydrogen is increasingly viewed as a promising energy carrier but its economic viability remains uncertain due to the lack of consensus on future demand and limited deployment of key components such as fuel cells in stationary stand-alone applications. This study investigates whether hybridising batteries with hydrogen can deliver meaningful cost benefits under future cost trajectories. Using a Monte Carlo framework we simulate 8000 scenarios across constant and seasonal load profiles varying the capital costs of batteries fuel cells electrolysers and hydrogen tanks based on 2025 estimates and 2050 projections. Our results show that hydrogen integration only becomes economically attractive when multiple component costs decline simultaneously. The fuel cell-to-battery power capital cost ratio emerges as the dominant driver of levelised cost of energy (LCOE) improvements. For constant loads median LCOE savings remain below 12 % with more than 5 % savings only achieved when the fuel cell cost is less than 7 times that of the battery. Seasonal nighttime loads offer a wider theoretical LCOE savings range (0–156 %) but substantial gains occur only under unrealistic cost mixes where battery costs remain high and fuel cell costs fall sharply. These findings highlight the sensitivity of hydrogen viability to load profile characteristics and cost interdependencies. They underscore the need for targeted cost reduction strategies particularly for fuel cells to justify added system complexity. These findings are important considerations for future investment and policy decisions.

Single Atom Catalysts (SACs) are an emerging frontier in heterogeneous electrocatalysis. They are made of metal atoms atomically dispersed on a matrix. A lot of attention has been dedicated to the study of Hydrogen Evolution Reaction (HER) mechanism due to its relevance in energy conversion technologies both with computational and experimental methods. The classical HER mechanism can be described by a Volmer–Heyrovsky–Tafel mechanism where the two desorption steps are competitive. The Volmer-Heyrovsky mechanism is conventionally proposed for single-atom catalysts. It has been computationally demonstrated that hydrogen complexes can form on SACs due to their analogy with homogeneous catalysts. Unfortunately it is hard to “visualize” these species experimentally. Electrochemical Impedance Spectroscopy (EIS) could be the most promising approach to study electrocatalytic mechanisms. In this work we present microkinetic and Electrochemical Impedance Spectroscopy models for HER on SACs describing Volmer-Heyrovsky and a mechanism mediated by the formation of hydrogen complexes. Our simulated data applied to a case study based on Pd@TiN show that Tafel plots will not suffice in the visualization of hydrogen complexes formation and will need the support of electrochemical impedance spectra in order to clarify the correct mechanism.

Decarbonizing industrial heat is critical for achieving climate targets. This study evaluates the economic viability of technologies for decarbonizing industrial heat in Europe through a techno-economic analysis. High-temperature heat pumps (HTHPs) and electric hydrogen and biomass boilers are compared in terms of levelized cost of heat (LCOH) under various scenarios including the impact of thermal storage leveraging dynamic electricity prices. In scenarios for the year 2030 we show that HTHPs leveraging free excess heat achieve LCOH values at least 30% to 60% lower than hydrogen boilers and up to 37% lower than biomass boilers. Integrating daily thermal storage reduces LCOH by up to 15% for heat pumps and 27% for electric boilers. By 2050 anticipated cost and efficiency improvements further enhance the competitiveness of heat pumps. These results highlight the economic advantage of HTHPs particularly when integrating excess heat and thermal storage.

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.

A hybrid energy system (HES) integrates various energy resources to attain synchronized energy output. However HES faces significant challenges due to rising energy consumption the expenses of using multiple sources increased emissions due to non-renewable energy resources etc. This study aims to develop an energy management strategy for distribution grids (DGs) by incorporating a hydrogen storage system (HSS) and demand-side management strategy (DSM) through the design of a multi-objective optimization technique. The primary focus is on optimizing operational costs and reducing pollution. These are approached as minimization problems while also addressing the challenge of achieving a high penetration of renewable energy resources framed as a maximization problem. The third objective function is introduced through the implementation of the demand-side management strategy aiming to minimize the energy gap between initial demand and consumption. This DSM strategy is designed around consumers with three types of loads: sheddable loads non-sheddable loads and shiftable loads. To establish a bidirectional communication link between the grid and consumers by utilizing a distribution grid operator (DGO). Additionally the uncertain behavior of wind solar and demand is modeled using probability distribution functions: Weibull for wind PDF beta for solar and Gaussian PDF for demand. To tackle this tri-objective optimization problem this work proposes a hybrid approach that combines well-known techniques namely the non-dominated sorting genetic algorithm II and multi-objective particle swarm optimization (Hybrid-NSGA-II-MOPSO). Simulation results demonstrate the effectiveness of the proposed model in optimizing the tri-objective problem while considering various constraints.

Marine and island power systems usually incorporate various forms of energy supply which poses challenges to the coordinated control of the system under diverse irregular and complex load operation modes. To improve the stability and self-sufficiency of island-isolated microgrids with high penetration of renewable energy this study proposes a coordinated control strategy for an island microgrid with PV HGT and HESS combining primary power allocation via low-pass filtering with a fuzzy logic-based secondary correction. The fuzzy controller dynamically adjusts power distribution based on the states of charge of the battery and supercapacitor following a set of predefined rules. A comprehensive system model is developed in Matlab R2023b integrating PV generation an electrolyzer HGT and a battery–supercapacitor HESS. Simulation results across four operational cases demonstrate that the proposed strategy reduces DC bus voltage fluctuations to a maximum of 4.71% (compared to 5.63% without correction) with stability improvements between 0.96% and 1.55%. The HESS avoids overcharging and over-discharging by initiating priority charging at low SOC levels thereby extending service life. This work provides a scalable control framework for enhancing the resilience of marine and island microgrids with high renewable energy penetration.

The study focused on designing a sustainable building involving rooftop agrivoltaics advanced glazing technologies and onsite hydrogen production for a residential property in Birmingham UK where green hydrogen produced by harnessing electricity generated by agrivoltaics system on rooftop of the building is employed to change the transparency of vacuum gasochromic glazing and refuel hydrogen-powered fuel cell vehicle using storage hydrogen for a sustainable building approach. The change in the transparency of the glazing reduces the energy requirement of the building according to the occupant’s requirement and weather conditions. This research investigates the performance of various rooftop agrivoltaic systems including vertical optimal 30◦ tilt and dome setups for both monofacial and bifacial agrivoltaic consisting of tomato farming. Promising results were observed for agrivoltaic systems with consistent tomato production of 0.31 kg/m2 with varying shading experienced due to the different photovoltaic setups. Maximum electricity is produced by bifacial 30◦ with 7919 kWh though the lowest LCOE can be observed by monofacial 30◦ with £0.061/kWh. It also compares the efficiency of vacuum gasochromic windows against double glazing vacuum double glazing electrochromic and gasochromic options which can play an essential role in energy saving and reduced carbon emission. Vacuum gasochromic demonstrated the lowest U-value of 1.32 Wm2 K though it has the highest thickness with 24.6 mm. Additionally the study examines the feasibility of small-scale green hydrogen production from the electricity generated by agrivoltaics to fuel hydrogen vehicles and glazing considering the economic viability. The results suggested that the hydrogen required by the glazing accounts for 52.56 g annually and the maximum distance that can be covered theoretically is by bifacial 30◦ which is approximately 64.23 km per day. The interdisciplinary approach aims to optimise land use enhance energy efficiency and promote sustainable urban agriculture to contribute to the UK’s goal of increasing solar energy capacity and achieving net-zero emissions while addressing food security concerns. The findings of this study have potential implications for urban planning renewable energy integration especially solar and sustainable residential design.

The cement industry a foundation of infrastructure development is responsible for nearly 7 % of global CO2 emissions highlighting an urgent need for scalable decarbonization strategies. This study investigates the technoeconomic feasibility of integrating on-site solar-powered green hydrogen production into cement manufacturing processes. A mixed-integer linear programming (MILP) model optimizes the design and operation of solar photovoltaics (PV) proton exchange membrane (PEM) electrolyzer and hydrogen storage for a representative cement plant in Texas. Five hydrogen substitution scenarios (10–30 % of thermal demand) were evaluated based on net present cost (NPC) levelized cost of hydrogen (LCOH) cost of CO2 avoided and greenhouse gas (GHG) emissions reduction. Hydrogen integration up to 30 % is technically viable but economically constrained with LCOH rising non-linearly from $58.7 to $95.3 GJ− 1 due to escalating component costs. Environmentally a 30 % hydrogen share could reduce total U.S. cement sector emissions by 22 %. While significant this confirms at present the solar-driven hydrogen serves as a partial solution rather than a standalone pathway to deep decarbonization suggesting it must complement other strategies like carbon capture electrification and other complementary technologies. The economic viability of this approach is entirely contingent on financial incentives as the investment tax credits of 80 % or higher are essential to enable cost parity with fossil fuels. This work provides a comprehensive techno-economic and environmental framework concluding immense economic barriers and that aggressive policy support is indispensable for enabling the transition to low-carbon cement manufacturing.