Egypt

This paper investigates innovative solutions to enhance the performance and lifespan of standalone photovoltaic (PV)-based microgrids with a particular emphasis on off-grid communities. A major challenge in these systems is the limited lifespan of batteries. To overcome this issue researchers have created hybrid energy storage systems (HESS) along with advanced power management strategies. This study introduces innovative multi-level HESS approaches and a related energy management strategy designed to alleviate the charge/discharge stress on batteries. Comprehensive Matlab Simulink models of various HESS topologies within standalone PV microgrids are utilized to evaluate system performance under diverse weather conditions and load profiles for rural site. The findings reveal that the proposed HESS significantly extends battery life expectancy compared to existing solutions. Furthermore the paper presents a novel energy management strategy based on the Reduced Fractional Gradient Descent (RFGD) algorithm optimization tailored for hybrid systems that include photovoltaic fuel cell battery and supercapacitor components. This strategy aims to minimize hydrogen consumption of Fuel Cells (FCs) thereby supporting the production of green ammonia for local industrial use. The RFGD algorithm is selected for its minimal user-defined parameters and high convergence efficiency. The proposed method is compared with other algorithms such as the Lyrebird Optimization Algorithm (LOA) and Osprey Optimization Algorithm (OOA). The RFGD algorithm exhibits superior accuracy in optimizing energy management achieving a 15% reduction in hydrogen consumption. Its efficiency is evident from the reduced computational time compared to conventional algorithms. Although minor losses in computational resources were observed they were substantially lower than those associated with traditional optimization techniques. Overall the RFGD algorithm offers a robust and efficient solution for enhancing the performance of hybrid energy systems.

In recent years traditional fossil fuels such as coal oil and natural gas have historically dominated various applications but there has been a growing shift towards cleaner alternatives. Among these alternatives hydrogen (H2) stands out as a highly promising substitute for all other conventional fuels. Today hydrogen (H2) is actively taking on a significant role in displacing traditional fuel sources. The utilization of hydrogen in gas turbine (GT) power generation offers a significant advantage in terms of lower greenhouse gas emissions. The performance of hydrogen-based gas turbines is influenced by a range of variables including ambient conditions (temperature and pressure) component efficiency operational parameters and other factors. Additionally incorporating an intercooler into the gas turbine system yields several advantages such as reducing compression work and maintaining power and efficiency. Many scholars and researchers have conducted comprehensive investigations into the components mentioned above within context of gas turbines (GTs). This study provides an extensive examination of the research conducted on hydrogen-powered gas turbine and intercooler with employed different methods and techniques with a specific emphasis on the different case studies of a hydrogen gas turbine and intercooler. Moreover this study not only examined the current state of research on hydrogen-powered gas turbine and intercooler but also covered its influence by offering the effective recommendations and insightful for guiding for future research in this field.

Sustainability goals include the utilization of renewable energy resources to supply the energy needs in addition to wastewater treatment to satisfy the water demand. Moreover hydrogen has become a promising energy carrier and green fuel to decarbonize the industrial and transportation sectors. In this context this research investigates a wind-photovoltaic power plant to produce green hydrogen for hydrogen refueling station and to operate an electrocoagulation water treatment unit in Ostrava Czech Republic’s northeast region. The study conducts a techno-economic analysis through HOMER Pro® software for optimal sizing of the power station components and to investigate the economic indices of the plant. The power station employs photovoltaic panels and wind turbines to supply the required electricity for electrolyzers and electrocoagulation reactors. As an offgrid system lead acid batteries are utilized to store the surplus electricity. Wind speed and solar irradiation are the key role site dependent parameters that determine the cost of hydrogen electricity and wastewater treatment. The simulated model considers the capital operating and replacement costs for system components. In the proposed system 240 kg of hydrogen as well as 720 kWh electrical energy are daily required for the hydrogen refueling station and the electrocoagulation unit respectively. Accordingly the power station annually generates 6997990 kWh of electrical energy in addition to 85595 kg of green hydrogen. Based on the economic analysis the project’s NPC is determined to be €5.49 M and the levelized cost of Hydrogen (LCH) is 2.89 €/kg excluding compressor unit costs. This value proves the effectiveness of this power system which encourages the utilization of green hydrogen for fuel-cell electric vehicles (FCVs). Furthermore emerging electrocoagulation studies produce hydrogen through wastewater treatment increasing hydrogen production and lowering LCH. Therefore this study is able to provide practicable methodology support for optimal sizing of the power station components which is beneficial for industrialization and economic development as well as transition toward sustainability and autonomous energy systems.

Demand response (DR) is a crucial element in the optimization of integrated energy systems (IESs) that incor porate distributed generation (DG). However its inherent uncertainty poses significant challenges to the eco nomic viability of IESs. This research presents a novel economic dispatch model for IESs utilizing information gap decision theory (IGDT). The model integrates various components to improve IES performance and dispatch efficiency. With a focus on hydrogen energy the model considers users’ energy consumption patterns thereby improving system flexibility. By applying IGDT the model effectively addresses the uncertainty associated with DR and DG overcoming the limitations of traditional methods. The research findings indicate that in relation to the baseline method the proposed model has the potential to reduce operating costs by 6.3 % and carbon emissions by 4.2 %. The integration of a stepwise carbon trading mechanism helps boost both economic and environmental advantages achieving a 100 % wind power consumption rate in the optimized plan. In addition the daily operating costs are minimized to 23758.99 ¥ while carbon emissions are significantly reduced to 34192 kg. These findings provide quantitative decision support for IES dispatch planners to help them develop effective dispatch strategies that are consistent with low-carbon economic initiatives.

Hydrogen energy as clean and efcient energy is considered signifcant support for the construction of a sustainable society in the face of global climate change and the looming energy revolution. Hydrogen is one of the most important chemical substances on earth and can be obtained through various techniques using renewable and nonrenewable energy sources. However the necessity for a gradual transition to renewable energy sources signifcantly hampers eforts to identify and implement green hydrogen production paths. Therefore this paper’s objective is to provide a technological review of the systems of hydrogen production from solar and wind energy utilizing several types of water electrolyzers. The current paper starts with a short brief about the diferent production techniques. A detailed comparison between water electrolyzer types and a complete illustration of hydrogen production techniques using solar and wind are presented with examples after which an economic assessment of green hydrogen production by comparing the costs of the discussed renewable sources with other production methods. Finally the challenges that face the mentioned production methods are illuminated in the current review.

Hydrogen and methane as secondary fuels in diesel engines can be promising solutions to meet energy demand. The current study investigated the effect of the specialty gases of different compositions on diesel engine performance and exhaust gases. Four gases with various compositions of exhaust gas recirculation (Carbon monoxide Carbon dioxide and Nitrogen) and fuels (Hydrogen and Methane) were used at various mass flow rates of 10 20 and 25 LPM (liter per minute) and various engine speeds of 2000 2500 3000 and 3500 rpm (revolutions per minute). The procured results revealed that adding specialty gases improved brake thermal efficiency and power. Similarly the brake-specific fuel consumption was also massively retarded compared to diesel due to the influence of the hydrogen and methane composition. However the fuel with the higher nitrogen reported less BTE (brake thermal efficiency) and comparatively higher exhaust gas temperature owing to the higher presence of nitrogen in their composition. Regarding emissions including exhaust gas recirculation dropped the formation of pollutants efficiently compared to diesel. Among various fuels Case 1 (30 % H2 5 % CH4 5 CO2 and 60 % CO) reported the lowest emission of NOx and Case 2 (25 % H2 5 % CH4 5 CO2 30 % CO and 35 % N2) of CO and CO2 emissions. Generally specialty gases with a variable composition of exhaust gas recirculation gases can be a promising sustainable replacement for existing fossil fuels.

Green hydrogen generation technologies are currently the most pressing worldwide issues ofering promising alternatives to existing fossil fuels that endanger the globe with growing global warming. The current research focuses on the creation of green hydrogen in alkaline electrolytes utilizing a Ni-Co-nano-graphene thin flm cathode with a low overvoltage. The recommended conditions for creating the target cathode were studied by electrodepositing a thin Ni-Co-nano-graphene flm in a glycinate bath over an iron surface coated with a thin copper interlayer. Using a scanning electron microscope (SEM) and energy-dispersive X-ray (EDX) mapping analysis the obtained electrode is physically and chemically characterized. These tests confrm that Ni Co and nano-graphene are homogeneously dispersed resulting in a lower electrolysis voltage in green hydrogen generation. Tafel plots obtained to analyze electrode stability revealed that the Ni-Co-nano-graphene cathode was directed to the noble direction with the lowest corrosion rate. The Ni-Co-nano-graphene generated was used to generate green hydrogen in a 25% KOH solution. For the production of 1 kg of green hydrogen utilizing Ni-Co-nano-graphene electrode the electrolysis efciency was 95.6% with a power consumption of 52 kwt h−1 whereas it was 56.212. kwt h−1 for pure nickel thin flm cathode and 54. kwt h−1 for nickel cobalt thin flm cathode respectively.