Power Generation Applications Research Articles

OIL DUST INDICATOR

An oil dust indicator is a crucial component in maintaining the efficiency and longevity of machinery and engines. It serves the dual purpose of monitoring both oil level and contamination levels, particularly from dust and particulate matter. The indicator typically consists of a sensor, a processor unit, and a display or alert mechanism. The sensor, often a combination of optical and pressure sensors, continuously monitors the oil. clarity and level. When dust or other contaminants accumulate in the oil, the sensor detects changes in clarity and triggers an alert. The processor unit interprets these signals and activates the display or alert mechanism, informing operators of the need for maintenance. In addition to indicating the need for oil replacement or cleaning, advanced oil dust indicators can also provide data on the severity of contamination, allowing for proactive maintenance planning. This capability can significantly reduce downtime and maintenance costs while optimizing the performance and lifespan of machinery and engines. Oil dust indicators find applications in various industries, including automotive, manufacturing, and power generation. They play a vital role in ensuring the smooth operation of critical machinery and equipment, making them indispensable tools for maintenance professionals and operators alike. This study proposes an advanced oil dust indicator that incorporates sensors for total dissolved solids (TDS), color, and pH levels to provide comprehensive monitoring of oil quality. Keywords: oil dust detector can sense dust in oil.

Influence of Operation Parameters on Thermohydraulic Performance of Supercritical CO2 in a Printed Circuit Heat Exchanger

The performance of recuperative printed circuit heat exchangers is critical in supercritical CO2 (sCO2) power generation applications. This article presents a three-dimensional numerical model of sCO2 flowing in a printed circuit heat exchanger and investigates its thermohydraulic performance under different operation conditions. The simulations employ the standard k-ε turbulent model, and consider entrance effects, conjugate heat transfer, real gas thermophysical properties and buoyancy effects. The heat exchanger operation parameters cover mass flux from 254.6 to 1273.2 kg/m2s, inlet temperature 50–150 °C and outlet pressure 100–250 bar on the cold side, and 300–500 °C and 75–150 bar on the hot side. Results show that increasing CO2 mass flux leads to a significantly increased heat transfer coefficient, a slight increase in temperature difference between the hot and cold CO2, as well as larger pressure drop and lower friction factor on both sides. Increasing the cold CO2 pressure, decreasing the cold CO2 temperature, and increasing the hot CO2 temperature result in a higher heat transfer rate of the heat exchanger. Increasing the CO2 temperature on each side causes increased pressure drops on both sides. Increasing the CO2 pressure on each side reduces the pressure drop on each side.

Rational Design of Cu Vacancies and Antisite Defects for Boosting the Thermoelectric Properties of CuGaTe2-Based Compounds.

CuGaTe2-based compounds show great promise in the application for high-temperature thermoelectric power generation; however, its wide bandgap feature poses a great challenge for enhancing thermoelectric performance via structural defects modulation and doping the system. Herein, it is discovered that the presence of GaCu antisite defects in the CuGaTe2 compound promotes the formation of Cu vacancies, and vice versa, which tends to form the charge-neutral structure defects combination with one GaCu antisite defect and two Cu vacancies. The accumulation of Cu vacancies in the structure of the (Cu2Te)x(Ga2Te3)1-x compounds evolves into twins and stacking faults. This in conjunction with GaCu antisite defects intensify the point defects phonon scattering, yielding a dramatic reduction on lattice thermal conductivity from 6.95 W m-1 K-1 for the pristine CuGaTe2 sample to 2.98 W m-1 K-1 for the (Cu2Te)0.45(Ga2Te3)0.55 sample at room temperature. Furthermore, the high concentration of charge-neutral defects combination narrows the band gap and increases the carrier concentration, leading to an improved power factor of 1.58 mW/mK2 at 600 K for the (Cu2Te)0.49(Ga2Te3)0.51 sample, which is 41% higher than for the pristine CuGaTe2 sample. Consequently, the highest ZT value of 0.82 is achieved at 915 K for Cu0.015(Cu2Te)0.48(Ga2Te3)0.52, which represents an enhancement of about 22% over that of the pristine CuGaTe2 compound.

Insight into Dynamic Characteristics of Concentrated Solar Power Systems with Calcium Looping Based on ZnO–Na2SO4 Co‐Doped CaO Composites

Concentrated solar power (CSP) integrated with calcium looping (CaL) technology has garnered significant interest as a solution to mitigate the issue of intermittency in solar power production. However, the deactivation of CaO‐based materials during cycling limits the application of CaL technology on a large scale. Herein, the dynamic characteristics of the CSP‐CaL system indirectly integrated with the s–CO2 Brayton cycle using CaO–ZnO–Na2SO4 composites are studied. Energy analysis shows that the energy storage density varies from 1328.13 to 1232.03 J g−1, and its average value increases by 32.0%. Round‐trip efficiency of the system varies from 40.0% to 39.5%, and its average value increases by 22.6%. Exergy analysis shows that the co‐doping of ZnO and Na2SO4 into CaO enhances the exergy efficiency of the calciner and the heat exchange network, but reduces the exergy efficiency of the carbonator. Exergy round‐trip efficiency of the CSP‐CaL system has slightly decreased from 44.0% to 43.4%, with an average increase of 22.8%. Techno‐economic analysis shows that the levelized cost of electricity for different sizes of CSP‐CaL systems using CaO–ZnO–Na2SO4 ranges from 176.44 to 153.70 $ MWh−1. Therefore, the CaO–ZnO–Na2SO4 composite shows promising prospects for application in solar thermal power generation.

Highly robust and porous cathode current collecting layer for flat-tubular solid oxide fuel cell stack applications

Solid oxide fuel cells (SOFCs) have gained great attention as a stationary power generation application due to their high efficiency, fuel flexibility and environmental friendliness. The devices and power age could be revolutionized with the commercialization of these technologies. The SOFC-based stationary power generator is one step closer to commercialization however, it is delayed due to the inherent bottleneck of insufficient long-term durability. The cathode current collecting layer (CCCL) is crucial in stack applications to minimize the contact loss between cell and metallic interconnects. Herein, we report an easy-to-fabricate and highly robust CCCL to boost electrochemical performance and long-term durability of flat tubular (FT) short stack. The tailored structure of the CCCL was employed in the fabrication of the FT short-stack. The G/Ag porous structure exhibited increased porosity of 61.2 %, thereby enhancing the mass transport and improving the overall performance and long-term durability. The four-cell FT stack was manufactured without an interconnect and open air-gas channel. Subsequently, the FT short-stack is tested for performance and long-term durability for elapsed 5000 h at a chronopotentiometry test. The porous layer of graphite/Ag on the cathode layer maintained structural integrity without defects and mechanical failure. Consequently, the stack voltage remains stable throughout operation owing to improved structural stability and uniform temperature distribution across four FT cell stack.

High wide-temperature-range thermoelectric performance in GeTe through hetero-nanostructuring

GeTe is emerging as promising medium-temperature thermoelectric material due to its highly competitive performance and good mechanical properties. Strong Rashba spin splitting was harnessed to markedly improve the Seebeck coefficient and power factor of Bi and Sn codoped GeTe at low-medium temperature. Moreover, it is found that Bi-Sn-Cu doping reduces the phase-transition temperature to extend better electrical transport behavior of cubic phase to low temperature. As a result, the electrical transport properties in low-medium temperature were overall enhanced. In the meanwhile, endotaxial hetero-nanostructures efficiently scatter phonons and play a dominant role on affecting phonon propagation. The lattice thermal conductivity was reduced to 0.2 W m−1K−1 at 673 K. Drive by strengthening Rashba effect and endotaxial hetero-nanostructures, a record-high average ZT (300–823 K) of 1.6 and a high ZT of 2.1 were obtained in lead-free GeTe-based compounds. The vast increase of ZT promotes GeTe as a promising candidate for a wide range of applications in waste heat recovery and power generation.

MXene-based thermoelectric fabric integrated with temperature and strain sensing for health monitoring

Wearable thermoelectric devices hold significant promise in the realm of self-powered wearable electronics, offering applications in energy harvesting, movement tracking, and health monitoring. Nevertheless, developing thermoelectric devices with exceptional flexibility, enduring thermoelectric stability, multifunctional sensing, and comfortable wear remains a challenge. In this work, a stretchable MXene-based thermoelectric fabric is designed to accurately discern temperature and strain stimuli. This is achieved by constructing an adhesive polydopamine (PDA) layer on the nylon fabric surface, which facilitates the subsequent MXene attachment through hydrogen bonding. This fusion results in MXene-based thermoelectric fabric that excels in both temperature sensing and strain sensing. The resultant MXene-based thermoelectric fabric exhibits outstanding temperature detection capability and cyclic stability, while also delivering excellent sensitivity, rapid responsiveness (60 ms), and remarkable durability in strain sensing (3200 cycles). Moreover, when affixed to a mask, this MXene-based thermoelectric fabric utilizes the temperature difference between the body and the environment to harness body heat, converting it into electrical energy and accurately discerning the body's respiratory rate. In addition, the MXene-based thermoelectric fabric can monitor the state of the body's joint through its own deformation. Furthermore, it possesses the capability to convert solar energy into heat. These findings indicate that MXene-based thermoelectric fabric holds great promise for applications in power generation, motion tracking, and health monitoring.

The potential of utilizing vertical borehole heat exchangers in residential buildings for the various climate zones of Saudi Arabia

Most of the literature concerning geothermal energy in Saudi Arabia has focused on power generation applications. This paper investigates the potential of utilizing ground-source heat pump (GSHP) with vertical borehole heat exchangers in residential buildings in the various climate zones and subsurface geologies of Saudi Arabia. Thermal loads of a typical residential building in Saudi Arabia were generated using eQuest software, then used in a model of GSHP system in TRNSYS. The performance and economics of the GSHP system was evaluated and compared with a typical air-source heat pump (ASHP) system for each location. The total borehole lengths in all zones were determined using the cooling load (the dominant load). The potential for employing GSHP systems was found to be not uniform across Saudi Arabia. The required length of the GHE ranged between 12 and 148 m/kW of cooling. The annual energy saving when employing GSHP instead of ASHP systems varied between 3 % to 19 %, and the building's electricity peak demand could be reduced between 5 % to 43 %. Although GSHPs reduced electrical and maintenance costs, their high drilling cost makes them economically unattractive under the present electric utility charge in Saudi Arabia.

Stable Radicals in Dihydrophenazine Derivatives-Doped Epoxy Resin for High Photothermal Conversion.

Organic radicals exhibit great potential in photothermal applications, however, their innate high reactivity with oxygen renders the preparation of stable organic radicals highly challenging. In this work, a series of co-doped radical polymers ares prepared by doping dihydrophenazine derivatives (DPPs) into the epoxy resin matrix. DPPs can form radical species through the electron transfer process, which are further stabilized by the complex 3D network structure of epoxy resin. Experimental results show that the photothermal conversion efficiency is as high as 79.9%, and the temperature can quickly rise to ≈130°C within 60 s. Due to the excellent visible light transmittance and mechanical properties of co-doped systems, this study further demonstrates their practical applications in energy-saving solar windows and thermoelectric power generation.

Enhancing visible light absorption of form-stable CH3COONa·3H2O composite phase change material and its application in thermoelectric power generation

The utilization of Phase Change Material (PCM) for solar heat storage represents an effective solar energy storage method. Nevertheless, this promising technology encounters several obstacles, particularly PCM leakage and dissatisfied solar absorptance. This study focuses on the development of a photothermal conversion composite PCM tailored for solar energy storage and its subsequent integration into a thermoelectric power generation system. The composite PCM was synthesized using an evaporation-impregnation method, with melamine foam (MF) serving as the adsorbent material, graphene oxide (GO) as the light-absorbing component, and sodium acetate trihydrate (SAT) as the thermal storage medium. It is shown that the MF demonstrates an exceptional adsorption capacity for SAT, whose mass fraction exceeds 99 % in the final composite. The composite PCM exhibits a remarkable melting enthalpy of 251.5 J/g, comparable to that of pure SAT. The integration of GO into MF/SAT improves the solar absorptance of the composite, elevating it from 23.3 % to 81.5 %, thereby enhancing the photothermal conversion performance. To assess the practical solar energy storage potential of the prepared PCM, a thermoelectric power generation system was designed and underwent a continuous 22-hour performance test in a real outdoor enviornment. The results reveal that the system is able to maintain voltage generation for about 10 hours after the sun disappears. This proves the superior photothermal conversion and heat storage capabilities of the prepared materials. This research offers a viable approach for direct solar energy storage and conversion to electricity, advancing renewable energy technologies.

Ultra-broadband absorber based on algorithmic optimization of MgF2–Fe stacked structure

Broadband absorbers possess a wide array of potential applications, including electromagnetic cloaking, solar energy harvesting, and solar power generation. However, achieving excellent ultra-broadband absorption with plasma-metal materials remains challenging due to their inherently narrow bandwidth. To tackle this issue, we propose an ultra-broadband absorber, free from lithography, composed of a multilayer stack of magnesium-iron fluoride (MgF2–Fe). In this study, we optimized the structural parameters of the absorber using a particle swarm optimization algorithm to achieve theoretically optimal absorptivity. Numerical simulations revealed that the absorber achieved an impressive theoretical average absorption of 98.4% across a broad wavelength range from ultraviolet to near-infrared (321–1800 nm). Importantly, it exhibited stable absorption performance at large incidence angles (0–70°), while maintaining high absorption efficiency. Furthermore, it demonstrated polarization independence at perpendicular incidence angles. Subsequently, experimental preparations and tests were conducted on absorber samples to evaluate their solar energy absorption capacity. Both experimental and theoretical comparisons underscored the promising potential of this structure for applications in solar energy collection, conversion, and solar power generation.

Design of a New Supersonic Shock Wave Generator and Application in Power Generation

Wind energy is a kind of renewable energy with great potential for development. This study mainly investigated the application of shock waves generated by high-pressure gases (wind energy) for generating energy. In this study, we designed a new supersonic shock wave generator that can be reused without disassembling and assembling bolts and developed a shock wave monitoring system. It could measure the velocity of the generated shock waves at about Mach 3–5, and the output pressure exceeded 900 kg/cm2 (more than 100 times the input pressure). Then, we developed a power generation system driven by supersonic shock waves based on the characteristics of the new shock wave generator, which could generate high-pressure and high-speed blast waves and could be reused. The shock wave generator can repeatedly generate high-pressure waves to drive the Tesla turbine and then rotate the magnetic energy generator for power generation. This paper used tank pressure, output pressure, gas flow, rotation speed, voltage, and current detected by the system to conduct power generation performance analysis. When the minimum rotation speed was set to 1500 rpm and three bulbs were turned on as loads, the system could generate an average voltage of 36.64 V and an average current of 211.01 mA as output (power about 7731.41 mW).

A Meta-Analysis Review: Nanoparticles as a Gateway to Optimized Boiling Surfaces.

Pool boiling is essential in many industrial manufacturing applications. In addition, it can become critical in the journey towards improving energy generation efficiency and accomplishing the goal of net-zero carbon emissions by 2050 via new or traditional power generation applications. The effectiveness of boiling is governed by the bubble cycle. The chemistry and topographical features of the surface being heated have been found to highly impact the boiling performance, such as in the case of pool boiling enhancement when employing hydrophilic and hydrophobic surfaces via nano/micro heater surface modification. Nevertheless, it is questionable how feasible it is to create these surfaces for large-scale applications due to their manufacturing and maintenance cost and complexity. The current work assesses whether the use of nanoparticles in traditional coolants could potentially unlock the mass production of optimised heating surface modification through a metadata literature review analysis. It was discovered that self-assembled layers created as a result of the deposition of nanoparticles in coolants undergoing pool boiling seem to behave most similarly to manufactured hydrophilic surfaces. The creation of enhanced patterned-heat transfer surfaces is shown to be possible via the use of a combination of different nanoparticle suspensions in coolants.

Enhancing sustainable energy production through biomass gasification gas technology: a review

This proposed research investigates the sustainable and innovative use of biomass gasification for generating electricity. Biomass gasification is a versatile and eco-friendly technology that converts organic materials, such as agricultural residues, forestry waste, and even municipal solid waste, into a valuable source of clean energy. This research delves into the various aspects of this technology, including its processes, efficiency, environmental impact, and potential applications in power generation. Biomass gasification gas, often referred to as syngas, presents a promising avenue for addressing the rising energy demand while lowering greenhouse gas emissions and preventing climate change. This research seeks to offer a thorough insight into the principles and practices behind biomass gasification, highlighting its role in the transition towards a sustainable and renewable energy future. The research will investigate the technical and economic feasibility of utilizing biomass gasification gas for electricity generation, examining the benefits, challenges, and opportunities associated with this alternative energy source. By addressing critical issues such as feedstock availability, gasifier technology, gas cleaning processes, and power plant integration, this study seeks to offer valuable insights into the potential of biomass gasification gas as a clean and renewable energy solution.

Study on photovoltaic/thermal application for water desalination and electricity power generation using high thermal conducting materials

Our research focus is the enhancement of potable water yield and Output Power (PO) which is achieved through by means of adding three metals like Copper, Aluminium and Iron. The composition comprises of Aluminium-0.17 %, Copper-2.42 % and Iron-2.64 % in volume percentage. Because of the fact that the samples contain high thermalproperties such as thermalconductivity and thermalexpansion it stores heat as an energy and delivers it into the fluid. The daily yield of solar-still is about 1.5 times the conventional solar-still that is the yield is increased from 1.30Ltr on a day to 1.90Ltr. This states that by increasing the amount of heat stored and heat transferred one could make the standard PV/T into a more reliable and cost-efficient one. The power production in the proposed PV panel seems to be 5 % higher than that of conventional PV panels. The power output is evidently increased from 48.4 Watts to 49.9 Watts. The net-profit of water produced per day in proposed system is found to be in the range of (0.3960–0.4143) USD but conventional one is (0.2562–0.2732) USD. The payback period is found to be lower for proposed setup it is only (240.9–259.15) days which is very profitable than that of the conventional setup is (328.5–357.7) days of payback period.

Enhancing Closed System Efficiency through CuO Nanofluids: Investigating Thermophysical Properties and Heat Transfer Performance

Working fluids play a crucial role in closed systems to ensure efficient performance, particularly in systems for heating, cooling, or power generation, where the heat transfer coefficient is pivotal. This study delves into the thermodynamic properties and stability of copper oxide (CuO) nanofluids as alternative working fluids in closed systems. Investigating colloidal suspensions of CuO nanoparticles, the research aims to enhance heat transfer efficiency. CuO nanoparticles, sized at 40nm and 80nm, were dispersed in base fluids like water, ethylene glycol, and oil sans surfactants. The study, divided into static and dynamic phases, examines key nanofluid properties including viscosity, thermal conductivity, specific heat, and heat transfer rate. Through methodologies such as KD2 Pro for thermal conductivity, rheometer for viscosity, and small heat exchanger for heat transfer rate analysis, the effects of volume concentration, temperature, and nanoparticle size on nanofluid performance were evaluated. Sedimentation analysis employed both quantitative (standard deviation calculations) and qualitative (sediment capture methods) approaches. The findings highlight the superior heat transfer rate of 40nm CuO nanofluid at 0.467% volume concentration which is 9.08 kJ/s, suggesting its potential to optimize system efficiency, particularly in heating, cooling, and power generation applications.

Cost-minimization and Implicit Innovative Training for Energy Prediction using Deep Neural Network

To alleviate adverse environmental impacts, power stations and energy grids must optimize resource application for power generation. Accordingly, soothsaying guests' energy consumption has come integral to every energy operation system. exercising data from smart homes, energy operation information can train deep neural networks to anticipate unborn energy demands. As the frugality advances, both energy product and consumption have steadily increased over the times. Amidst global enterprises over energy force and environmental challenges, this study introduces a new vaticination approach using neural networks. By using statistical data from the energy assiduity, these networks directly read changes in energy product and consumption trends. Numerical findings validate the efficacity of this neural network- grounded vaticination system, emphasizing its significance in energy conservation sweats. Predicting energy consumption stands as a pivotal bid in energy conservation enterprise. Support vector retrogression, famed for its efficacity in handlingnon-linear data retrogression challenges, has surfaced as a prominent tool for soothsaying structure energy consumption. Through analysis of literal data, it's apparent that the relationship between lighting energy consumption and its impacting factors is non-linear.

Improvement of X-ray Photoelectric Conversion Performance of MAPbI3 Perovskite Crystals by Ionic Liquid Treatment

Although perovskite has great potential in optoelectronic devices, the simultaneous satisfaction of material stability and high performance is still an issue that needs to be solved. Most perovskite optoelectronic devices use quantum dot spin coating or the gas-phase growth of perovskite thin films as the photoelectric conversion layer. Due to stability limitations, these materials often experience a significant decrease in photoelectric conversion efficiency when encountering liquid reagents. The self-assembled growth of hybrid perovskite crystals determines superior lattice ordering and stability. There are three types of ionic liquids—[Emim]BF4, EMIMNTF2, and HMITFSI—that can effectively enhance the X-ray photoelectric conversion performance of hybrid perovskite crystal CH3NH3PbI3 (MAPbI3), and the enhancement in the photocurrent leads to an improvement in the sensitivity of X-ray detectors. We soak the perovskite crystals in an ionic liquid and perform two treatment methods: electrification and dilution with ETOH solution. It is interesting to find that MAPbI3 perovskite single crystal materials choose the same optimized ionic liquid species in X-ray detection and photovoltaic power generation applications, and the effect is quite the opposite. Compared with untreated MAPbI3 crystals, the average photocurrent density of Electrify-HMITFSI MAPbI3 increased by 826.85% under X-ray excitation and the sensitivity of X-ray detectors made from these treated MAPbI3 crystals significantly increased by 72.6%, but the intensity of the PL spectrum decreased to 90% of the untreated intensity.

Heavy elemental compound addition enhancing thermoelectric performance of Chromium Silicide synthesized by Spark plasma sintering

Silicide-based materials drive great potential in developing mid-temperature range thermoelectric generators (TEGs) applications. However, realizing the efficient and stable silicide materials is still a constraint for its real potential device applications. Chromium silicide will likely become p-type thermoelectric materials in this direction for thermoelectric power generation applications. However, high thermal conductivity values impede the figure-of-merit (zT). The present work adopts the chromium silicide, adding different weight percentages of well-known ZrCoSbSn compounds employing the compaction spark plasma sintering (SPS) technique. By adopting these combinations, the thermal conductivity is significantly reduced by enhanced scattering of heat-carrying phonons by multiple interfaces. Also, the maximum power factor value of ≃ 2.1 × 10−3 W/mK2 is achieved by employing a CrSi2 -ZrCoSbSn compound addition. The enhanced figure-of-merit value (zT) ≃ 0.26 is realized in the temperature at 623 K for the CrSi2-5wt% ZrCoSbSn compound material.

Multiphysics performance evaluation of thermoelectric generator arrays

Thermoelectric generators (TEGs) are widely used nowadays in heat recovery and power generation applications. TEGs are connected in series and/or parallel configurations in an array to meet the voltage and/or current requirements of electric load. Therefore, it is necessary to examine the electrical performance of different TEG array configurations employed in TEG systems. In the present study, an experimentally validated hydro-thermoelectric multiphysics computational model is employed by integrating the computational fluid dynamics (CFD) approach with the TEG model to test the electrical performance of various TEG array configurations and determined load voltage, current, associated power, and conversion efficiency. Each TEGs array configuration’s performance is evaluated by varying the hot water temperature from 27 °C to 42 °C as well as hot and cold water flowrate from 0.5 L/min to 2 L/min. Various configurations including series and a combination of series and parallel connections were designed. The findings show that the series configuration of the TEGs array generates higher electric power than series and parallel combined configurations whereas the latter achieves the maximum power point at a higher electric current than the series configuration. The comparative analysis of CFD model with the experimental results indicates a maximum discrepancy of 7 %. For thermoelectric power-generating systems, the proposed model might serve as a benchmark for optimizing TEGs array configurations according to the electric load requirements.