Search

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article aims to examine a novel combined power and refrigeration system, using renewable and waste heat sources suitable for low-temperature applications. The present system is an integrated Kalina cycle and ejector refrigeration system to generate power and refrigeration simultaneously. To improve the vapour generation, the separator vapour fraction is used as a decision variable. Relative irreversibility and efficiency defect as two important parameters considered in this system for an investigation to identify the weaker components. The combined system generates power and refrigeration with two different mediums by the incorporation of the heat exchanger at the turbine exhaust. The novel system's energy and conventional exergy evaluation are carried out through Python Software. The optimum values of decision variables: turbine concentration, separator vapour fraction, entrainment ratio, expander ratio, split ratio and turbine concentration are identified using Python software from an opted range of variables. The maximum value of net power output, first law efficiency for power generation system, combined system, second law efficiency for power generation system, combined system, refrigeration effect and coefficient of performance are obtained as 113 kW, 8.85%, 11.83%, 93.44%, 81.29%, 38.07% and 0.118, respectively, at higher separator vapour fraction. Among the components considered in the combined power generation system, the condenser and LTRGN account for the higher exergy destruction rate of 30.41% and 25.53%. The coefficient of performance is maximized at a higher value of the refrigeration effect. The turbine pressure at the inlet is increased with increments in turbine work on choosing the higher value of the expander ratio. The higher exergetic value components are not emphasized to focus on improvement. [ABSTRACT FROM AUTHOR]

Global warming and environmental pollution from greenhouse gas emissions are hitting an all-time high consistently year after year. In 2022, energy-related emissions accounted for 87% of the overall global emissions. The fossil fuel-based conventional power systems also need timely upgrades to improve their cycle efficiency and reduce their impact on the environment. Supercritical CO2 systems and cycles are gaining attention because of their higher efficiencies and their compatibility with varied energy sources. The present work is a detailed overview of the recent developments in supercritical CO2-based power generation technologies. The supercritical CO2-based Brayton and Rankine power cycles and their improvisations in industrial applications are also discussed in detail. The advances in heat exchanger technology for supercritical CO2 systems are another focus of the study. The energy, exergy, and economical (3E) analysis is carried out on various supercritical CO2 power cycles reported in the literature and the data are concisely and intuitively presented. The review concludes by listing the identified directions for future technology development and areas of immediate research interest. A roadmap is proposed for easing the commercialization of supercritical CO2 technologies to immediately address the growing challenges and concerns arising from energy-related emissions. [ABSTRACT FROM AUTHOR]

Three FeCrAl alloys (APMT, EF100 and EF101) from Kanthal® and the reference Ni‐Cr Alloy 625 were used as weld cladding materials on tube shields in the evaporator tube bank of a waste‐fired combined heat and power plant. For each alloy type, the overlay welded tube shields were placed in both roof and floor positions within the evaporator for 6 months. The metal‐loss rate, the microstructure and hardness of the overlay welds before and after exposure and the corrosion products were analysed. The results showed higher metal‐loss rates in the welds placed in the roof position, confirming heterogeneities in the evaporator bank environment. Alloys were ranked from higher to lower erosion–corrosion resistance as follows: APMT ≈ Alloy 625 > EF101 > EF100. The analysis of the corrosion attacks showed a significant variation among the alloys, from a primarily homogeneous corrosion attack on APMT to intergranular corrosion in EF100 and pit formation in EF101. [ABSTRACT FROM AUTHOR]

Solid state nanochannels provide significant practical advantages in many fields due to their interesting properties, such as controllable shape and size, robustness, ion selectivity. But their complex preparation processes severely limit their application. In this study, a simple cost‐effective method to fabricate single nanochannel by embedding a single polyethylene oxide (PEO) nanofiber is presented. Firstly, PEO nanofibers are prepared by electrospinning, and then a single PEO nanofiber are precisely transferred to the target sample using a micromanipulation platform. Then, PDMS is used for embedding, and finally, the PEO nanofiber is dissolved to obtain a single nanochannel. Unlike other methods of preparing nanochannels by embedding nanofibers, this method can prepare single nanochannel. The diameter of nanochannel can be as fine as 100 nm, and the length can reach several micrometers. The power generation between two potassium chloride solutions with various combinations of concentrations was investigated using the nanochannel. This low‐cost flexible nanochannel can also be used in various applications, including DNA sequencing and biomimetic ion channel. [ABSTRACT FROM AUTHOR]

The objective of this paper is to design a smart grid of an ordinary plant with two renewable resources (solar PV and wind turbine) plants. The burnout of fossil fuels globally has created a hasty need for alternative energy sources to meet current energy demands. To address this issue, a hybrid power system has been developed, which combines clean energy sources, such as solar PV and wind, with fossil fuel generators, power conditioning systems and energy storage systems. This hybrid system adduces higher efficiency, more flexibility in environmental and planning benefits compared to relying solely on diesel generators. However, employing solar and wind energy has the disadvantage that they are erratic and dependent on climatic and meteorological variations, which may not coincide with the timing of energy need. This not only has an influence on the system's functionality but also causes batteries to be disposed of too soon. The results illustrated the root mean square (r.m.s) power behaviour over a 24 hour each day in May, 2020 according to the weather climate in Mosul city. Finally, it has been confessed that the individual power generated either by solar PV or by wind turbine was enough to supply the load. [ABSTRACT FROM AUTHOR]

The use of renewable energy sources to replace conventional energy sources like fossil fuels is essential. Solar panels are the most widespread technology for clear energy production. However, is crucial to raise the efficiency of solar panels. A large portion of sunlight is reflected by the front surface of the panel and thus the use of an Anti-Reflecting Coating (ARC) has become significant in raising the efficiency of solar panels, through reducing the reflection losses. The ARCs made of natural extracts were utilized to improve the efficiency of Silicon solar panels. The natural extracts were produced from Kailashpati fruit juice and Badminton ball tree flower powder. In the synthesis of these natural extracts, monometallic gallium chloride nanoparticles were used to check their effect on the efficiency of solar power generation. The novelty of this paper is the attempt to mathematically calculate the absorbance of the ARCs, at a particular wavelength, with the use of the refractive indices and thicknesses of ideal ARCs. [ABSTRACT FROM AUTHOR]

As the most common energy source of spacecraft, photovoltaic (PV) power generation has become one of the hottest research fields. During the on-orbit operation of spacecraft, the influence of various uncertain factors and the unbalanced inertial force will make the solar PV wing vibrate and degrade its performance. In this study, we investigated the influence of mechanical vibration on the output characteristics of PV array systems. Specifically, we focused on a three-segment solar panel commonly found on satellites, analyzing both its dynamic response and electrical output characteristics under mechanical vibration using numerical simulation software. The correctness of the simulation model was partly confirmed by experiments. The results showed that the maximum output power of the selected solar panel was reduced by 5.53% and its fill factor exhibited a decline from the original value of 0.8031 to 0.7587, provided that the external load applied on the panel increased to 10 N/m2, i.e., the vibration frequency and the maximal deflection angle were 0.3754 Hz and 74.9871°, respectively. These findings highlight a significant decrease in the overall energy conversion efficiency of the solar panel when operating under vibration conditions. [ABSTRACT FROM AUTHOR]

Conduit hydropower systems improve the efficiency of water supply networks (WSNs) by utilizing excess network pressure for providing renewable energy while significantly reducing leakage. A major problem in using conduit hydropower is finding the optimum location for installing power generation devices like in-line turbines or pumps operating as turbines (PATs). This paper suggests an optimization model to find the optimum location for placing in-line turbines in WSNs using a non-parametric Rao algorithm for optimal daily power generation. The methodology is tested on a hypothetical 5-Node network and later applied to a benchmark 25-Node network. Installing turbines at optimum locations reduced network leakage by 76332.00 and 380473.87 L, representing approximately 2.57% & 2.94% of the total water demand of 5-Node and 25-Node networks, respectively, and generated 184.12 & 547.48 kWh/day of hydropower. [ABSTRACT FROM AUTHOR]

Photo-assisted microbial fuel cells (PMFCs) are novel bioelectrochemical systems that employ light to harvest bioelectricity and efficient contaminant reduction. In this study, the impact of different operational conditions on the electricity generation outputs in a photoelectrochemical double chamber configuration Microbial fuel cell using a highly useful photocathode are evaluated and their trends are compared with the photoreduction efficiency trends. As a photocathode, a binder-free photo electrode decorated with dispersed polyaniline nanofiber (PANI)−cadmium sulphide Quantum Dots (QDs) is prepared here to catalyse the chromium (VI) reduction reaction in a cathode chamber with an improvement in power generation performance. Bioelectricity generation is examined in various process conditions like photocathode materials, pH, initial concentration of catholyte, illumination intensity and time of illumination. Results show that, despite the harmful effect of the initial contaminant concentration on the reduction efficiency of the contaminant, this parameter exhibits a superior ability for improving the power generation efficiency in a Photo-MFC. Furthermore, the calculated power density under higher light irradiation intensity has experienced a significant increase, which is due to an increment in the number of photons produced and an increase in their chance of reaching the electrodes surface. On the other hand, additional results indicate that the power generation decreases with the rise of pH and has witnessed the same trend as the photoreduction efficiency. [ABSTRACT FROM AUTHOR]

With the development of renewable energy technologies, the recovery and utilization of low-grade energy based on hydroelectric effect have drawn much attention owing to its environmental friendliness. Herein, a novel hydroelectric generator utilizing sodium alginate-graphene oxide (SA-GO) fibers is proposed, which is ecofriendly and low-cost. These fibers with a length of 5 cm and a diameter of 0.15 mm can generate an open circuit voltage (Voc) of approximately 0.25 V and a short circuit current (Isc) of 4 µA. By connecting SA-GO fibers in either series or parallel, this combination can power some electronic devices. Furthermore, these fibers enable the recovery of low-grade energy from the atmosphere or around the human body. Both experimental and theoretical analysis confirm that the directional flow of protons driven by water molecules is the main mechanism for power generation of SA-GO fibers. This study not only presents a simple energy transformation method that is expected to be applied to our daily life, but also provides a novel idea for the design of humidity electricity-generation devices. [ABSTRACT FROM AUTHOR]

This study presents a systematic analysis of Brayton batteries using Ebsilon Professional® simulations. Over 200,000 concept configurations were evaluated, with less than 1% proving physically feasible. The research aimed to assess electricity generation; coupled generation of electricity and heat; coupled generation of electricity and cooling; and coupled generation of electricity, heat, and cooling, all with or without waste heat integration. Efficiency ranged from 20% to 50% for electricity generation alone, with higher efficiencies at a compressor discharge temperature of 625 °C compared to 450 °C. Co-generation improved the overall efficiency, although at the expense of power efficiency. Notably, simultaneous electricity, heat, and cooling generation solutions were absent within the study's parameters. Lead concepts, predominantly air-based systems with or without charging line recuperators and heat exchange at various stages, were identified. These will undergo detailed dynamic system simulations, focusing on thermal energy storage. Comparison with the existing literature was limited due to differing parameters and topologies, highlighting the value of this systematic analysis in identifying optimal solutions. [ABSTRACT FROM AUTHOR]

In the not-too-distant future, humans will return to the Moon and step foot for the first time on Mars. Eventually, humanity will colonize these celestial bodies, where living and working will be commonplace. Energy is fundamental to all life. The energy that people use to sustain themselves on Earth, and in particular on these other worlds, is the integrated, safe production of electrical power, day and night. This paper proposes a radically new solution to this problem: Solar Tracking by day and a Solar Rechargeable Calcium Oxide Chemical Thermoelectric Reactor by night. Called the "Robotic End Effector for Lunar and Martian Geological Exploration of Space" (REEGES) Day/Night Power Generator Station, this form of thermoelectric power generation is mathematically modeled, simulation is performed, and a concept model design is demonstrated in this paper. The results of the presented simulation show the maximum total system output capability is 9.89 V, 6.66 A, and 65.9 W, with an operating time of up to 12 h, through a scalable design. This research provides instructions to the Space Research Community on a complete and novel development methodology for creating fully customized, configurable, safe, and reliable solar/thermoelectric day/night power generators, specifically meant for use on the Moon and Mars, using the Proportional-Integral-Derivative++ (PID++) Humanoid Motion Control Algorithm for its operation on a computationally lightweight microcontroller. [ABSTRACT FROM AUTHOR]

PbSnS2 crystals have the advantage of high performance and low cost as emerging thermoelectric materials. Herein, thermoelectric properties of PbSnS2 crystals are substantially boosted through the strategy of lattice plainification to manipulate micro‐defect. By introducing Ni elements into n‐type PbSnS2, the intrinsic Pb/Sn cation vacancies are compensated by Ni, achieving a plainer lattice and higher carrier mobility. Meanwhile, the charge density is enhanced due to the orbital hybridization between the 3d orbital of Ni and the 3p orbital of the neighboring S, further facilitating the carrier transport. Consequently, an ultrahigh carrier mobility of ≈312 cm2 V−1 s−1 in n‐type PbSnS2+0.0010Ni crystal is obtained with a largely enhanced ZT of ≈0.6 at 300 K along the in‐plane direction, and a maximum ZT of ≈1.2 can be obtained at 473 K. Moreover, a 7‐pair thermoelectric device composed of n‐type PbSnS2+0.0010Ni crystal and p‐type commercial Bi0.4Sb1.6Te3 is fabricated, which can produce a cooling temperature difference of ≈19.4 K. And a single‐leg device composed of the PbSnS2+0.0010Ni crystal realizes a maximum power generation efficiency of ≈2.7%. The work further optimizes the low‐cost and earth‐abundant PbSnS2 crystals as potential application candidates in thermoelectric cooling and power generation. [ABSTRACT FROM AUTHOR]

Integrating two advanced techniques, such as solar thermal evaporation (STE) for freshwater production and hydrovoltaic (HV) for electricity generation, makes a considerable attempt to attain basic energy needs. Here in this work, a crisscross porous carbonized ethanol‐treated potato cake as a hydrovoltaic device (CHV) is fabricated. CHV device is a highly stable, portable, eco‐friendly device with a maximum output voltage of 0.23 V and current of 5 µA under ambient conditions. This is further raised to 0.5 V when exposing 1 sun illumination (1 kW m2). Voltage studies are done by varying the wind flow, relative humidity, and bulk water temperature to confirm the device's HV property and dependent factors. The potential application of the device is tested by glowing an LED light connected with 5 CHV devices in series. It is continuously delivered output till the bulk water is dry. The shelf‐life ability of CHV is also analyzed after 1 year of usage and provided nearly the same outcome. Therefore, this single device with dual‐energy harvesting gives a significant solution to society's energy and water crisis for a better tomorrow. [ABSTRACT FROM AUTHOR]

Microbial fuel cell (MFC) is a promising technology for recovering energy in wastewater through bacterial metabolism. However, it always suffers from low power density and electron transfer efficiency, restricting the application. This study fabricated the MnCo2S4–Co4S3/bamboo charcoal (MCS-CS/BC) through an easy one-step hydrothermal method, and the material was applied to carbon felt (CF) to form high-performance MFC anode. MCS-CS/BC-CF anode exhibited lower Rct (10.1 Ω) than BC-CF (17.24 Ω) and CF anode (116.1 Ω), exhibiting higher electrochemical activity. MCS-CS/BC-CF anode promoted the electron transfer rate and resulted in enhanced power density, which was 9.27 times higher (980 mW m−2) than the bare CF (105.7 mW m−2). MCS-CS/BC-CF anode showed the best biocompatibility which attracted distinctly larger biomass (146.27 mg/μL) than CF (20 mg/μL) and BC-CF anode (20.1 mg/μL). The typical exoelectrogens (Geobacter and etc.) took dramatically higher proportion on MCS-CS/BC-CF anode (59.78%) than CF (2.99%) and BC-CF anode (26.67%). In addition, MCS-CS/BC stimulated the synergistic effect between exoelectrogens and fermentative bacteria, greatly favouring the extracellular electron transfer rate between bacteria and the anode and the power output. This study presented an efficient way of high-performance anode electrocatalyst fabrication for stimulating MFC power generation, giving suggestions for high-efficient energy recovery from wastewater. [ABSTRACT FROM AUTHOR]

Much progress has been made in hydrovoltaic materials and devices. However, the power conversion efficiency of hydrovoltaic devices is still low. One of the main factors that determine the efficiency is the properties of hydrovoltaic materials. Herein, the research status of hydrovoltaic materials is summarized from the perspectives of synthetic materials, macroscopic biomaterials, and micro biomaterials, as well as the hydrovoltaic devices based on these materials. [ABSTRACT FROM AUTHOR]

The heterogeneous and homogeneous combustion-based homogeneous charge compression ignition of fuel-lean methane-air mixtures over alumina-supported platinum catalysts was investigated experimentally and numerically in free-piston micro-engines without ignition sources. Single-shot experiments were carried out in the purely homogeneous and coupled heterogeneous and homogeneous combustion modes, involved temperature measurements, capturing the visible combustion image sequences, exhaust gas analysis, and the physicochemical characterization of catalysts. Simulations were performed with a two-dimensional transient model that includes detailed heterogeneous and homogeneous chemistry and transport, leakage, and free-piston motion to gain physical insight and to explore the heterogeneous and homogeneous combustion characteristics. The micro-engine performance concerning combustion efficiency, mass loss, energy density, and free-piston dynamics was investigated. The results reveal that heterogeneous reactions cause earlier ignition, which is very favourable for the micro-device. Both purely homogeneous and coupled heterogeneous and homogeneous combustion of methane-air mixtures in a narrow cylinder with a diameter of 3 mm and a height of approximately 0.3 mm are possible. Heat losses result in higher mass losses. The coupled heterogeneous and homogeneous mode can not only significantly improve the combustion efficiency, in-cylinder temperature and pressure, output power and energy density, but also reduce the mass loss because of its lower compression ratio and less time spent around the top dead centre and during the expansion stroke, indicating that this coupled mode is a promising combustion scheme for micro-engines.

Traditional solar updraft power plants work during the daytime as it is dependent on solar radiation to generate electricity. Hence, energy productivity, efficiency, and performance are limited. This work presents a novel attempt to increase the productivity of a traditional solar updraft system by combining it with a downdraft technology in one system, the Twin-Technology Solar System (TTSS). The TTSS comprises two co-centric inner and external solar towers, turbines, water sprinklers, and a collector. The inner tower works as a traditional solar updraft system, where the air is heated under the collector due to irradiance and then moved up the chimney due to the pressure column. While the external tower creates a downdraft wind by spraying water at the hot ambient air at the top of the tower. The hot air instantly absorbs the water and descends the tower to interact with the turbines at the bottom to produce electricity. This mode is independent of solar irradiance and can operate day and night. Hence, the TTSS generates electricity, daytime and night. A mathematical simulation model was developed based on the proposed system's energy and mass balance equations to assess performance. The TTSS generated 752,763 kWh of electricity annually, 2.14 folds higher than a traditional solar updraft system. Consequently, a reduction of 677 tons of CO2 was achieved with production. The design is suitable for deployment in hot and dry weather areas, such as remote villages and deserts. Future work will investigate introducing other technologies to boost the TTSS performance.

This research explores biomass gasification for power generation in rural areas of developing countries, utilizing a 20 kW U-flow-shaped gasification system developed at Ashikaga University. While small-scale power systems typically rely on reciprocating or modified diesel engines, which face issues due to tar produced by biomass gasifiers, this study employed a piston-less rotary engine. Performance evaluations were conducted at various engine speeds and gasifier operational modes, demonstrating continuous power generation for approximately six hours. Improved maintenance of rotary engines could benefit rural users, with potential efficiency gains through thermal energy recovery, although tar filtration needs enhancement. The experimental findings reveal continuous power generation for approximately six hours under both operational conditions, with the closed-top operation outperforming the open-top counterpart in terms of power output. However, control over power output and gasifier temperatures is more straightforward in the open-top operation. Gasifier performance was assessed based on fuel consumption rate and system efficiency, with consumption rates varying by rotary engine speed, measuring 2.0 kWh/kg at 2800 rpm and 2.3 kWh/kg at 3200 rpm, and 2.9 kWh/kg at 3600 rpm. Cold gas efficiency of the U-shaped gasifier was 63.4%, and energy conversion efficiency reached 9.4% at 2800 rpm operation. At 3200 rpm operation, cold gas efficiency improved to 79.8%, but energy conversion efficiency decreased to 7.3%. The rotary engine's energy conversion efficiency was lower than that of a gas engine. Nonetheless, if the rotary engine reduces maintenance needs, it could benefit rural users. Efficiency can be improved through thermal energy recovery.

The increasing interest in leveraging green ammonia to mitigate carbon emissions in fertilizer production is paralleled by an expanding acknowledgment of its potential as a fuel for decarbonizing the electricity sector, particularly in high-efficiency gas turbine power plants. Co-firing ammonia with hydrogen presents a promising method for integrating ammonia into existing infrastructures. Within this context, the development of efficient technology for ammonia cracking presents a potential avenue for deploying ammonia in gas turbines. The objective of this study is to conduct a preliminary techno-economic evaluation and uncertainty analysis of two cracking technologies namely a membrane reactor and a conventional FTR (Fired Tubular Reactor) for the co-firing of ammonia with hydrogen in a CCGT (Combined Cycle Gas Turbine) plant. The integration of a membrane reactor during the cracking stage demonstrates a remarkable improvement in the system's thermal efficiency, surpassing traditional approaches by over 25%. Additionally, it brings about an approximate 10% reduction in the levelized cost of hydrogen (LCOH), despite a higher initial capital expenditure (CAPEX). At the CCGT level, the discrepancy in levelized cost of electricity (LCOE) narrows, as it is strongly influenced by the cost of ammonia constituting 80% of the LCOE. Beyond LCOE, the widespread adoption of these systems also faces challenges due to material scarcity. Analysis reveals that revamping just 1 GWe of CCGT assets using membrane reactors would for example necessitate approximately 0.11% of the global palladium supply, and 10% of the global ruthenium production. Considering the limited availability of these resources, coupled with their high demand across multiple sectors and the possibility of external factors such as geopolitical tensions, this strategy seems unfeasible. To tap into this market, future research should prioritize the exploration of alternative membrane materials, such as carbon molecular sieves, and catalysts, like nickel. • Two cracking technologies for NH3–H2 co-firing in CCGT plants have been evaluated. • Membrane reactors reduces H2 cost by 10% and raise efficiency by 25%. • The study indicates the need to explore new materials for this market (e.g. carbon molecular sieve membrane). [ABSTRACT FROM AUTHOR]

This paper explores a novel method of focuses on utilizing ammonia as a hydrogen carrier that can be decomposed to produce hydrogen, the combustion of which produces steam for generating power in turbines. The simulation for such a process is performed on ASPEN Plus software. The key steps include compressing the ammonia and passing it through a fluidized bed reactor (FBR) for its decomposition, subsequently compressing the products before combusting the hydrogen with compressed air in a combustor and extracting power from the hot products through a series of turbines. The article examines in detail the effect of different parameters on the performance of the individual components as well as the overall process. Specifically, considerable emphasis is placed on the effects of varying pressures and temperatures on the functioning of the FBR at different catalyst loadings, their effects on the combustor performance and the dependence of the overall process on the air flowrate in the combustor. The comprehensive analysis elucidated on the energy efficiency of the process and it identified conditions at 2 bar pressure and 550 °C temperature as being the most favorable for ammonia decomposition and subsequent turbine power output while lean hydrogen combustion with excess air making the inlet hydrogen concentration less than 20% resulted in optimum temperatures at the turbine inlet. • The paper explores ammonia as a hydrogen carrier in the power plant industry through ASPEN PLUS process simulations. • The initial step is to decompose ammonia into nitrogen and hydrogen in a fluidized bed reactor, the optimum operating condition of which turns out to be 2 bar pressure and 550 °C. • The next steps involve mixing air with the decomposition products, pressurizing them to 40-60 bar, combusting hydrogen in a plug flow reactor to produce steam and finally expanding it in a series of turbines to generate power. • Detailed flow and more importantly, energy analysis of all the process units show ammonia as a very effective hydrogen carrier for applications in power plants. [ABSTRACT FROM AUTHOR]

Landfill leachate, which is a complicated organic sewage water, presents substantial dangers to human health and the environment if not properly handled. Electrochemical technology has arisen as a promising strategy for effectively mitigating contaminants in landfill leachate. In this comprehensive review, we explore various theoretical and practical aspects of methods for treating landfill leachate. This exploration includes examining their performance, mechanisms, applications, associated challenges, existing issues, and potential strategies for enhancement, particularly in terms of cost-effectiveness. In addition, this critique provides a comparative investigation between these treatment approaches and the utilization of diverse kinds of microbial fuel cells (MFCs) in terms of their effectiveness in treating landfill leachate and generating power. The examination of these technologies also extends to their use in diverse global contexts, providing insights into operational parameters and regional variations. This extensive assessment serves the primary goal of assisting researchers in understanding the optimal methods for treating landfill leachate and comparing them to different types of MFCs. It offers a valuable resource for the large-scale design and implementation of processes that ensure both the safe treatment of landfill leachate and the generation of electricity. The review not only provides an overview of the current state of landfill leachate treatment but also identifies key challenges and sets the stage for future research directions, ultimately contributing to more sustainable and effective solutions in the management of this critical environmental issue. [ABSTRACT FROM AUTHOR]

Artificially tilted multilayer thermoelectric devices (ATMTDs) have attracted widespread attention due to their advantages of simple and stable structure. In this study, n-type Ag2Te and p-type Bi0.5Sb1.5Te3 (BiSbTe), as two typically excellent room-temperature thermoelectric materials, were used to assemble ATMTDs. The interface structure and chemical composition of Ag2Te/BiSbTe ATMTDs were characterized and their transverse thermoelectric performance was evaluated. The results indicated that the interfacial diffusion and reaction at Ag2Te/BiSbTe interface leads to the formation of AgSbTe2 phase with thickness approximately 22 μm and the interface established an ohmic-type electrical contact with a small contact resistance. After structural optimization, the Ag2Te/BiSbTe ATMTD with titled angle 45° and aspect ratio 3 exhibited a large transverse voltage of reaches 6.78 mV at a temperature difference of 80 K, reaching 91.1% of the theoretical value. This work demonstrates that Ag2Te/BiSbTe ATMTDs possess a good interfacial contact and transverse thermoelectric performance without significant power loss, maintaining excellent power generation and thermal response properties. [ABSTRACT FROM AUTHOR]

This paper proposes a solution to address the challenges of high storage and transport costs associated with using hydrogen ( H 2 ) as an energy source. It suggests utilizing ammonia ( N H 3 ) as a hydrogen carrier to produce H 2 onsite for hydrogen gas turbines. N H 3 offers higher volumetric hydrogen density compared to liquid H 2 , potentially reducing shipping costs by 40%. The process involves N H 3 pyrolysis, which utilizes the heat waste from exhaust gas generated by gas turbines to produce H 2 and nitrogen ( N 2 ). Numerical simulations were conducted to design and understand the behaviour of the heat recapture N H 3 decomposition system. The design considerations included the concept of the number of transfer units and heat exchanger efficiency, achieving a heat recapture system efficiency of up to 91%. The simulation of N H 3 decomposition was performed using ANSYS, a commercial simulation software, considering wall surface reactions, turbulent flow, and chemical reaction. Parameters such as activation energy and pre-exponential factor were provided by a study utilizing a nickel wire for N H 3 decomposition experiments. The conversion of N H 3 reached up to 94% via a nickel-based catalyst within a temperature range of 823 K to 923 K which is the exhaust gas temperature range. Various factors were considered to compare the efficiency of the system, including the mass flow of N H 3 , operating gauge pressure, mass flow of exhaust gas, among others. Result showed that pressure would not affect the conversion of N H 3 at temperatures above 800 K, thus a lower amount of energy is required for a compression purpose in this approach. The conversion is maintained at 94% to 97% when lower activation energy is applied via a ruthenium-based catalyst. Overall, this study showed the feasibility of utilizing convective heat transfer from exhaust gas in hydrogen production by N H 3 pyrolysis, and this will further enhance the development of N H 3 as the potential H 2 carrier for onsite production in hydrogen power generation. [ABSTRACT FROM AUTHOR]

The major cause of the shortage of land reserve water is the lack of rainfall, which makes the proper operation of irrigation systems extremely important. A major concern for farmers these days is water scarcity. Pakistan is an important agricultural nation, and a major part of the economy depends on agriculture. This study analyses soil moisture monitoring and automatic plant watering systems since they are really helpful in all kinds of weather. In this study, a prototype is designed and implemented using Arduino-based automation sensors employed for the control and observation of a solar-powered smart irrigation system. Implementation of an Arduino solar-built automatic irrigation system for the agricultural farm, which robotically switches the motor when water is essential, delivers for irrigation when the moisture of the earth drives under the threshold value rate, which turns on the pump on autopilot. An estimation was carried out for solar power energy potential agriculture system conditions using soil and humidity sensors. The measurements and mathematical formulation were observed to monitor the effectiveness of solar-based power generation. This study can implement an automatic programming- based controller system to switch irrigating water constructed utilizing soil moisture to sense soil wetness. This scheme senses the dryness of the irrigation area. This system improves the conventional system alternated with an automatic system. This analysis is conducted for a 20-watt power panel integrated with a 5-watt electrical drive with a battery capacity of 1200 m-Ah. A modified energy model was used to determine the agricultural load for a 5-watt DC motor. To develop a facility analysis a simulation-based solar-powered irrigation model is designed using Dip Trace Software. The results showed a cumulative analysis to implement this system inspired by smart, sustainable, clean, renewable energy technologies, which meet the farmer's demands, significantly increase the productivity of farming, and reduce wastage of water and energy. As compared to previous studies, this system detects the soil humidity and temperature range to cross the set point, so the pump will be on for 10 seconds, and this system will be able to operate without any human interaction. This system is inspired by renewable energy technologies and can operate without conventional power systems. [ABSTRACT FROM AUTHOR]

Libya is facing a serious challenge in its sustainable development because of its complete dependence on traditional fuels in meeting its growing energy demand. On the other hand, more intensive energy utilization accommodating multiple energy resources, including renewables, has gained considerable attention. This article is motivated by the obvious need for research on this topic due to the shortage of applications concerning the prospects of the hybridization of energy systems for electric power generation in Libya. The 283 MW single-cycle gas turbine operating at the Sarir power plant located in the Libyan desert is considered a case study for a proposed Integrated Solar Combined Cycle (ISCC) system. By utilizing the common infrastructure of a gas-fired power plant and concentrating solar power (CSP) technology, a triple hybrid system is modeled using the EES programming tool. The triple hybrid system consists of (i) a closed Brayton cycle (BC), (ii) a Rankine cycle (RC), which uses heat derived from a parabolic collector field in addition to the waste heat of the BC, and (iii) an organic Rankine cycle (ORC), which is involved in recovering waste heat from the RC. A thermodynamic analysis of the developed triple combined power plant shows that the global power output ranges between 416 MW (in December) and a maximum of 452.9 MW, which was obtained in July. The highest overall system efficiency of 44.3% was achieved in December at a pressure ratio of 12 and 20% of steam fraction in the RC. The monthly capital investment cost for the ISCC facility varies between 52.59 USD/MWh and 58.19 USD/MWh. From an environmental perspective, the ISCC facility can achieve a carbon footprint of up to 319 kg/MWh on a monthly basis compared to 589 kg/MWh for the base BC plant, which represents a reduction of up to 46%. This study could stimulate decision makers to adopt ISCC power plants in Libya and in other developing oil-producing countries. [ABSTRACT FROM AUTHOR]

The imperative to combat climate change necessitates the rapid implementation of technologically advanced, zero-emission renewable energy solutions, particularly considering the mounting energy demands and the pressing need to mitigate global warming. The proposed SOFC system, integrated with a modified Rankine Cycle and CCUS technology, offers a highly efficient, renewable system with a net-zero carbon footprint, utilising green biogas as an alternative. The fully integrated system at continuous operation does not require outside heat sources and, besides, its main electricity production can supply 231 households with hot sanitary water. A base case and sensitivity analysis of the system was conducted studying different operating parameters. The base case simulation, conducted at SOFC/reformer operating temperatures of 850 °C/650 °C and operating parameters S/C = 2.5, Uf = 0.70 Ua = 0.1806, yielded an overall efficiency of 71.64%, with a 67.70% electrical efficiency. Further simulations demonstrated that a 1.60% and 1.53% increase in the overall and electrical efficiencies of the proposed alternative, respectively, would be achieved at SOFC/reformer operating temperatures of 950 °C/650 °C. The simulated hybrid system represents a competitive installation in the renewable energy market, which offers a viable and sustainable alternative to traditional forms of energy generation. [ABSTRACT FROM AUTHOR]

This paper explores the complex interactions that exist between national ancillary service markets and local flexibility in Türkiye's changing power landscape. The significance of grid flexibility is escalating, especially with the country's transition from a predictable energy generation model to one predominantly fueled by intermittent renewable sources, coupled with the imminent integration of nuclear power. Ancillary services, encompassing functions such as frequency control, voltage regulation, and system restart, play a pivotal role in upholding grid stability. The study particularly underscores the significance of frequencyrelated ancillary services in preserving grid equilibrium. Moreover, it emphasizes how important electricity distribution businesses are as major players in improving grid stability. These businesses can actively participate in ancillary service markets and support grid stability by utilizing local flexibility solutions like distributed generation, energy storage, and demand response. This benefits the grid as well as consumers. The central objective of the study is to explore the synergies between local flexibility solutions and national ancillary markets. A case study is employed to evaluate the potential benefits and profitability associated with the integration of these components for an electrical distribution company. A combination solution utilizing solar panels, battery storage systems, electric vehicle charging infrastructure, and a natural gas turbine within the gearbox company's network is the subject of a case study that is presented. The concept of local flexibility and its mutually beneficial relationship with the national auxiliary service markets are also clarified in the study. The findings demonstrate the potential profitability and advantages of battery storage for the national energy grid. A substantial increase in prices for Frequency Restoration Reserve is imperative to render the natural gas turbine economically sustainable. [ABSTRACT FROM AUTHOR]