Electric Power Generation Research Articles

The emerging chemistry of self-electrified water interfaces.

Water is known for dissipating electrostatic charges, but it is also a universal agent of matter electrification, creating charged domains in any material contacting or containing it. This new role of water was discovered during the current century. It is proven in a fast-growing number of publications reporting direct experimental measurements of excess charge and electric potential. It is indirectly verified by its success in explaining surprising phenomena in chemical synthesis, electric power generation, metastability, and phase transition kinetics. Additionally, electrification by water is opening the way for developing green technologies that are fully compatible with the environment and have great potential to contribute to sustainability. Electrification by water shows that polyphasic matter is a charge mosaic, converging with the Maxwell-Wagner-Sillars effect, which was discovered one century ago but is still often ignored. Electrified sites in a real system are niches showing various local electrochemical potentials for the charged species. Thus, the electrified mosaics display variable chemical reactivity and mass transfer patterns. Water contributes to interfacial electrification from its singular structural, electric, mixing, adsorption, and absorption properties. A long list of previously unexpected consequences of interfacial electrification includes: "on-water" reactions of chemicals dispersed in water that defy current chemical wisdom; reactions in electrified water microdroplets that do not occur in bulk water, transforming the droplets in microreactors; and lowered surface tension of water, modifying wetting, spreading, adhesion, cohesion, and other properties of matter. Asymmetric capacitors charged by moisture and water are now promising alternative equipment for simultaneously producing electric power and green hydrogen, requiring only ambient thermal energy. Changing surface tension by interfacial electrification also modifies phase-change kinetics, eliminating metastability that is the root of catastrophic electric discharges and destructive explosions. It also changes crystal habits, producing needles and dendrites that shorten battery life. These recent findings derive from a single factor, water's ability to electrify matter, touching on the most relevant aspects of chemistry. They create tremendous scientific opportunities to understand the matter better, and a new chemistry based on electrified interfaces is now emerging.

Ray Tracing and Simulation of Parabolic Dish Collectorusing Soltrace for Vehicle Applications

Concentrated solar power has the potential to produce large-scale renewable energy sources. Concentrated solar energy is produced using mirrors, reflective materials, or lenses on conical surfaces such as a parabolic dishes, parabolic troughs, towers, Fresnel reflector systems, and dish sterling collectors. The concentrated light source was converted into heat energy, which drove the heat engine into an electrical power generator. To gain more heat energy, the solar rays must be trapped and concentrated on their conical focus points. To increase the net overall efficiency of the system, it is vital to know the optical performances of the subsystem formed by the solar receiver and the parabolic concentrator. In this study, a beam of incident solar rays was traced on a parabolic dish collector, and a simulation is performed for concentrator behaviour using the ray-tracing code SolTrace developed by the NREL laboratory. For an incident radiation of 1000 W/m2 (considering 10000 photon rays), their optical performance and solar heat flux were simulated. The results show that the number of elements in SolTrace varies depending on the CFD mesh density, the number of rays utilised in the Monte Carlo technique and their impact on generating a resolution-independent solution. Investigating the ray tracing of the disc concentrator, the propulsive energy for viable applications can be analysed.

Subcritical and supercritical Rankine steam cycles, under elevated temperatures up to 900°C and absolute pressures up to 400 bara

The Rankine cycle is a conceptual arrangement of four processes as a closed vapor power thermodynamic cycle, where a working fluid (especially water as a liquid, as a vapor, and as a liquid-vapor mixture) can be used to convert heat into mechanical energy (shaft rotation). This cycle and its variants are widely used in electric power generation through utility-scale thermal power plants, such as coal-fired power plants and nuclear power plants. In the steam-based Rankine cycle, water should be pressurized and heated to be in the form of very hot high-pressure water vapor called “superheated steam,” before the useful process of expansion inside a steam turbine section occurs. If the absolute pressure and temperature of the superheated steam are both above the critical values for water (220.6 bara and 374.0°C), the cycle is classified as “supercritical.” Otherwise, the cycle is classified as “subcritical.” This study considers the impact of the temperature and pressure, independently, on the performance of a steam Rankine cycle. Starting from a representative condition for a subcritical cycle (600°C peak temperature and 50 bara peak absolute pressure), either the peak temperature or the peak absolute pressure of the cycle is increased with regular steps (up to 900°C, with a temperature step of 50°C, and up to 400 bara, with a pressure step of 50 bar). The variation of five scale-independent performance metrics is investigated in response to the elevated temperature and the elevated pressure. Thus, a total of 10 response curves are presented. When the temperature increased, all the five response variables were improved in a nearly linear profile. On the other hand, increasing the pressure did not give a monotonic linear improvement for each response variable. In particular, the cycle efficiency seemed to approach a limiting maximum value of 45% approximately, where further increases in the pressure cause diminishing improvements in the efficiency. When varying the peak pressure, an optimum minimum ratio of (water-mass-to-output-power) is found at 203 bara, although the cycle efficiency still increases beyond this value. In the present research work, the web-based tool for calculating steam properties by the British company Spirax Sarco Limited, and the software program mini-REFPROP by NIST (United States National Institute of Standards and Technology) were used for finding the necessary specific enthalpies (energy content) of water at different stages within the steam cycle. Both tools were found consistent with each other, as well as with the Python-based software package Cantera for simulating thermo-chemical-transport processes. The results showed that if the peak temperature reaches 900°C, a gain of about 5 percentage points (pp) in the thermal cycle efficiency becomes possible (compared to the case of having a base peak temperature of 600°C), as the predicted efficiency was found to increase from 38.60% (base case) to 43.67%. For the influence of the steam peak pressure, operating in the subcritical regime but close to the critical point appears to be a good choice given the gradual decline in efficiency gains at higher pressures. About 4.7 percentage point increase was found at the high subcritical peak pressure of 200 bara (compared to a base subcritical peak pressure of 50 bara). The results of this study also showed that the liquid water droplet mass fraction at the steam turbine exit diminishes from 11.00% at 600°C to only 1.48% at 900°C, which is favorable. This mass fraction grows from 11.00% at 50 bara to 27.89% at 400 bara, which is not acceptable. Every 100°C increase in the superheating temperature between 600°C and 900°C was found to cause aa increase in the cycle thermal efficiency by about 1.69 percentage points, and simultaneous a beneficial increase in the steam quality at the turbine exit by about 3.17 percentage points.

Simple and sustainable electric power generation by free evaporation of liquids from the surface of a conventional thermoelectric generator

Liquid evaporation on the surface of a thermoelectric generator can be applied for lighting up a bulb.

Modelling and performance analysis of hybrid electrical power generation system for condensate fractionation plant

Refinery industries are mostly installed at the rural area or distant islands considering the hazardous conditions and transportation facilities. However, more often than not these islands or rural areas have no grid connections to facilitate electrification for these kinds of plants. Even if a grid extension is possible, the availability of power cannot be guaranteed in such rural areas. In any case, disruption in power continuity is not allowed for keeping every subsystem (e.g., heating, reaction subsystem) of the refinery industries under running condition. So, having a standalone, failure free and robust power generation system is a prerequisite criterion before starting up such plants in those areas. Diesel generator is the inevitable choice to meet the demand of electricity in such situation, although the cost of running a diesel generator dependent power system to support these sophisticated plants has been quite a challenge. However, with the available modern technologies, it is possible to think of a stable renewable power generation system that can ensure power availability at any time with the lowest possible operating cost. In this paper, a hybrid power generation system is modelled for a Condensate Fractionation Plant (CFP). Optimization, performance analysis and validation of the proposed model are assessed by using HOMER simulation tool

Agriculture Residue based Electric Power Generation

The foundation of a country’s sustainable economic development rests on the availability of an ample supply of electrical energy. To remain competitive on the global stage, India must ensure the provision of sufficient electricity infrastructure to fuel its economic progress. Achieving developed nation status necessitates extending electricity access to every corner of the country. India, being primarily an agrarian nation, possesses abundant agricultural waste resources. This wealth of agricultural waste presents a valuable opportunity for electricity generation. Notably, agricultural husk emerges as a promising raw material for electricity generation, provided it undergoes proper and systematic processing. This endeavor aims to introduce the concept of electricity generation from agricultural husk, with a particular focus on rural areas in India. Agricultural husk-based small and medium power plants offer a pragmatic solution for generating and distributing electricity to underserved rural communities. Within this paper, we delve into the availability of agricultural husk resources in India, explore various feasibility studies, and elucidate the principal processes for generating electricity from rice husk. The overarching goal is to support India’s journey towards future development. This paper serves as a valuable resource for both governmental and private sector entities interested in establishing agricultural husk-based power plants in rural India. Ultimately, we aspire for this document to serve as a practical guideline for addressing the substantial electricity demand prevalent in India’s rural areas.

Power enhancement in PV arrays under partial shaded conditions with different array configuration

Solar Photovoltaic systems are used for electrical power generation, and they provide an alternative source to non-renewable energy sources like coal, oil, natural gas and nuclear energy. Photovoltaic arrays used in PV systems may be subjected to partial shading conditions, thereby affecting power generation because of higher power mismatch losses. Due to an uneven distribution of irradiation condition, some of the bypass diodes turned on and affect the power generation in a photovoltaic array. The mismatch losses are due to the output from PV panels subjected to different irradiations because of non-uniform partial shading conditions. The power loss can be reduced by uniformly distributing the partially shaded condition over the entire PV array. In this work different shaped 4 × 4 array configuration is proposed to overcome the effect of partial shading condition, thereby providing lower mismatch losses. Simulations under different partial shading conditions are carried out using MATLAB Simulink, and the experimental setupis carried out for the proposed array configuration for 4 × 4 PV array and the results are discussed.

Experimental studies of thermo-mechanical characteristics of nitinol alloy springs

The article deals with the research of heat-sensitive elements based on Nitinol material - a wire with a diameter of 1.0 mm, which in the form of springs can potentially be used with the appropriate geometric parameters in the design of a heat engine of an electric power generation system. Research allows to determine the thermomechanical characteristics of springs from this alloy, namely the study of the influence of the magnitude of the preliminary deformation of such elements on the generated force. Heat hardening of the nitinol wire was carried out at a temperature of 400 to 500 °C for 4.5 hours. The study of thermomechanical characteristics was carried out when heating a thermosensitive element (spring) in water from a temperature of 20 °C to 100 °C, force measurements were performed with a spring dynamometer. Thermosensitive elements - two springs made of Nitinol alloy - were chosen for research in this work. The paper shows the model and general view of the experimental setup for the knowledge of thermomechanical characteristics of springs. The thermomechanical characteristics of the springs at different amounts of their deformation have been constructed. Graphs are presented that show that the functional dependence of the maximum generated force on the amount of spring deformation is close to linear. The interpolation method was used in the work, the corresponding coefficients were calculated and the functional dependence was constructed. The resulting dependence allows you to increase the limits of determining the maximum generated force from the amount of spring deformation and will be necessary when modeling the characteristics of a heat engine. Experimental studies have established that a significant influence on the amount of force generated by a spring made of Nitinol alloy is determined by the amount of spring deformation. At a spring deformation of 160 mm and a temperature of 100 oC, the generated force was 4...4.05 N, and at a deformation of 100 mm - 1.75...1.85 N.

Bifacial dye-sensitized solar cells for indoor and outdoor renewable energy-based application

Bifacial solar cells (BFSCs) are designed to enhance electrical power generation per unit area compared to traditional monofacial cells. They accomplish this by capturing sunlight from both the front and rear surfaces.

First-principles guidelines to select promising van der Waals materials for hybrid photovoltaic-triboelectric nanogenerators.

Photovoltaic (PV) devices play a key role in solar-to-electricity energy conversion at small and large scales; unfortunately, their efficiency heavily depends on optimal weather and environmental conditions. The optimal scenario would be to extend the capabilities of PV devices so that they are also able to harvest energy from environmental sources other than light. An optimal solution is represented by hybrid photovoltaic-triboelectric (PV-TENG) devices which have both photovoltaic and triboelectric capabilities for electric power generation. Two-dimensional transition metal dichalcogenides (TMDs) are highly promising candidates for such PV-TENG devices, thanks to the easy tunability of their electrical, optical, mechanical, and chemical properties. In this respect, we here propose a quantum mechanical study to identify suitable TMD-based chemical compositions with optimal photovoltaic and triboelectric generation properties. Among the considered materials, we identify MoTe2/WS2, MoS2/WSe2, WS2/TiO2, WS2/IrO2, and MoS2/WTe2 as the most promising bilayer compositions; under operative conditions, the band gap varies in the range 0.51-1.61 eV, ensuring the photovoltaic activity, while the relative motion of the layers may produce an electromotive force between 1.21 and 3.21 V (triboelectric generation) with a TMD/TMD interface area equal to about 200 Å2. The results constitute theoretical guidelines on how to check if specific chemical compositions of TMD bilayers are optimal for a combined photovoltaic and triboelectric power generation. Thanks to its generality, the presented approach can be promptly extended to van der Waals heterostructures other than those here considered and implemented in automated workflows for the search of novel low-dimensional materials with target PV and TENG response.

THE SOCIAL COST OF CARBON EVALUATION BASED ON CARBON CAPTURE AND STORAGE TECHNOLOGIES FOR POWER GENERATION PLANTS

Power plants produce electricity using high amounts of fossil fuels such as coal. Using these fossil fuels releases very high emissions into the atmosphere. Carbon capture and storage (CCS) applications have been developed to reduce these emissions. Thus, by capturing 96% of the CO<sub>2</sub> formed from the burning of fuels in power plants, the global warming potentials emitted by conventional electricity generation can be reduced by up to 80%. The study investigated applications of CCS options to reduce emissions during electricity generation, CO<sub>2</sub> emissions, pre-combustion, post-combustion, and oxyfuel coupled global warming potentials. The reCiPe midpoint method has been taken into account for CO<sub>2</sub> emission. CCS options calculate the reduction in global warming potential. The study accepts that hard and brown coal is used as fuel in power plants that produce electricity. Finally, for the three cities with the highest electricity consumption in Turkey, the global warming potential emission in conventional electricity generation power plants burning brown coal is calculated as 43.4 kilotons for plants burning brown coal. It has been calculated as 6.2 kilotons in power plants using oxyfuel CCS and burning hard coal. Ten-year life for Istanbul, for hard coal burning and pre-combustion related discount rate of 1% and 3 $/ton social cost of carbon; The social cost of carbon is calculated as $102.8 million.

Improve the Electric Power Generation Issue by Cognitive Thinking

The enormous increase in power demand due to the prevalent heat wave, the worst power shortage in the last decades, and lack of sufficient fossil fuels like natural gas, coal, oil, etc. has attracted the attention of researchers worldwide. One of the main reasons behind the problem is the mismanagement of proper regulation of the electrical power generation unit. This paper looks at cognitive thinking to address and improve this issue by noting that it is the process of gaining knowledge and understanding through thought, experience, and the senses that have enabled researchers to infer cognitive processes. Highly controlled and rigorous methods of study have always been employed to enable the work. Thermal energy power plants have been taken as the source of power generation and genetic algorithm (GA), fuzzy, and PID (Proportional, Integral, Derivative) controllers are used. All these controllers handle and control sudden changes in load frequency and power. For better and more effective results of the system, combined feedback has been obtained with the help of MATLAB Simulink software. The results obtained from the combined feedback are tabulated, which shows that all the controllers improve the electrical power generation issue by modulating the changes in load frequency and power, but the GA controller produces effective, efficient, and better results by adjusting to the changes in less time. The use of this cognitive thinking of the controller helps in the proper management of power demand which automatically improves and controls the power generation.

BOEING 787 Model Daha Elektrikli Uçak Sistem Yenilikleri ve Araştırılan Sorunları

In recent years, MEA technology has brought about developments in the field of power electronics, fault-tolerant architecture, electro-hydrostatic actuators, flight control systems, high-density electric motors, power generation and conversion systems. Non-propulsive systems in traditional aircraft systems, ıt is powered by a combination of different secondary power sources such as hydraulic, pneumatic, mechanical and electrical while the more electric aircraft (MEA) concept ensures the use of optimum electrical power for all non-propellant systems. 
 The goal of future aircraft technology is to replace the majority of non-electrical power-using systems, such as environmental control and engine starting, with electrical systems to improve various aircraft characteristics such as efficiency, emissions, reliability and maintenance costs. B787 series aircraft, the first civil aircraft with more electric aircraft features of modern times, ıt features composite fuselage and wing profiles, fly-by-wire flight controls, advanced cockpit and General Electric or Rolls-Royce engines. Different from previous designs, Boeing has minimized the use of air from the engines in the B787 technology and makes extensive use of electrically powered systems instead of traditional pneumatically powered systems. B787 new generation passenger aircraft, ıt is anticipated that significant improvements such as aircraft weight, fuel consumption, total life cycle costs, carbon neutrality, ease of maintenance and aircraft reliability will reduce the effects of adverse environmental conditions.
 In this study, the system innovations of the B787 aircraft model, which is a more electric aircraft concept and introduces different testing and working methods throughout the design process, and the problems caused by the new systems were investigated.

Study of an autonomous solar power plant for a motorhome

Problem. An RV combines two essential features desired by modern travelers: the ability to relax in unconventional locations while still being able to work remotely if your job requires remote access. However, if you're accustomed to the conveniences that rely on electrical power, you'll find yourself searching for places to connect to the centralized power grid. Alternatively, you'll need to seek solutions to this issue. One of the most intriguing and effective solutions is the installation of a low-power solar power station on the RV, based on photovoltaic modules. This solution enables you to park and enjoy any location you prefer while benefiting from all the available technologies powered by electricity. Goal. This study aims to investigate the installation of an autonomous solar power station on an RV and determine its electrical power generation capacity. Methodology. Analytical research methods were employed to explore the development and application of solar energy conversion methods and devices to generate electricity. Experimental research methods and mathematical techniques for processing experimental data were also utilized. Results. The RV type suitable for installing an autonomous solar power station has been identified, specifically the Roller Team Sirio 599. An investigation of its equipment in terms of electricity consumption has been conducted. Furthermore, a self-sustaining solar station has been proposed for the selected RV, and the electricity generation schedule of this station has been studied. The electricity consumption by RV appliances has been thoroughly examined. Originality. This study explored the volt-ampere characteristics of photovoltaic modules and their power generation dependency on the load. The investigated photovoltaic modules demonstrate maximum operational efficiency in the active load range from 3 ohms to 3.5 ohms. Practical Value. The research findings indicate that starting from March, the solar power station on the RV is fully capable of meeting its electricity consumption needs. In the winter months, particularly in November, in Ukraine's climate conditions, this solar power station may only cover a portion of electricity consumption needs. Considering that electrical devices are often used for heating the RV, this solar power station should not be relied upon as the primary source of electrical power.

Desalination Fuel Cell Stacks: Scaling up the Co-Production of Electricity and Clean Water

The world faces a rising demand for potable water and electricity, while a lack of clean water and use of polluting electricity sources are major hazards1. Nowadays reverse osmosis (RO) is widely used for sea and brackish water desalination2, where RO consumes ~3-4 kWh/m3 for seawater desalination3. A new class of water treatment technologies is emerging that is distinguished from the classical methods by utilizing chemical energy to power both water treatment and electricity generation simultaneously from a single electrochemical cell. When using the hydrogen/oxygen redox couple, such a cell is termed a desalination fuel cell (DFC) which was introduced by our group in 20204.A DFC utilizes a fuel cell anode and cathode to catalyze the chemical-to-electrical energy conversion, as well as a cation and anion exchange membrane to desalinate the feedwater flowing through the cell. A device with a single feed channel (figure a) was able to produce up to 10 kWh/m3 while desalinating water with sea-water level salinity4. In order to for this nascent technology to become practical, scale-up strategies need to be proposed and demonstrated.In this work we show results from the first scaled DFC, where we utilize scaling rules associated with electrodialysis by increasing the number of membrane pairs to allow either two or three feed channels (Figure b). We find the three feed channel device was associated with high voltage loss in the ohmic region and lower limiting current (figure c), but the salt concentration behaved linearly as a function of the current density as expected (figure d). The main voltage losses are clearly emanated from the cathode and the anode sides as the membranes potential loss was proven to be insignificant5. We showed that implementing higher acid concentration in the catholyte and higher base concentration in the anolyte channels can significantly improve performance of the stack. Figure (e) shows results using three different anolyte and catholyte solutions, with highest open circuit voltage (OCV) and improved polarization performance for 0.5M HClO4 and 0.5M NaOH in the catholyte and the anolyte, respectively. We also investigated the feed flow rate impact on DFC polarization performance and salt removal. Overall, we show successful implementation of a scaled-up DFC.

Effect of Asymmetrically Reinforced Membrane on Anion Exchange Membrane Fuel Cell

Anion Exchange Membrane Fuel Cells (AEMFCs) is promising for the generation of electric power from hydrogen, with the expected possible replacement of precious metal catalysts by Earth abundant ones.[1-2] Beyond the independent properties of core materials (AEM, anode and cathode catalysts), the water management during operation is key to achieving high power density, but also high longevity. Thin AEMs are critical to achieve high AEMFC power performance, as the back-diffusion of water from anode to cathode critically helps to mitigate anode flooding. [3] Due to the high swelling of hydrated AEMs, good mechanical durability of thin AEMs however typically requires the introduction of a reinforcement, often a porous polytetrafluoroethylene (PTFE) membrane filled with the anion exchange ionomer.Here, we investigated the structure of different commercial AEMs and their behavior in operating AEMFC. We identified that the position of the reinforced layer (PTFE or other) strongly differs from one type of AEM to another. In the case of strongly asymmetric through-plane position of the PTFE layer (Fig. 1a), the positioning of the PTFE reinforcement close to anode or to cathode has a significant impact on initial power performance (Fig. 1b). A better performance and improved stability was observed with the PTFE layer close to the anode, suggesting that the asymmetric structure can improve the water management in such configuration. The presentation will discuss the results obtained on different commercial AEMs, and whether the asymmetric structure of AEM can be combined with PTFE hydrophobized anodes for even improved performance. The effect of the reinforcement position on the water management was also studied operando by two techniques. With high energy X-ray diffraction technique on an AEMFC under current load, the water distribution profile across the MEA thickness could be obtained from phase deconvolution analysis. With the use of relative humidity sensors at the outlet of anode and cathode of a regular AEMFC setup, [4] the water balance at a given current load could be established and compared for the two different positionings of reinforced AEM.The results shed light on the importance of identifying the position of PTFE reinforcement in commercial or in-house AEM for AEMFC application, with potential implications also for AEM electrolyzers or water-CO2 co-electrolyzers.

Minimizing Coke Formation at La0.3Ca0.7Fe0.7Cr0.3O3-δ Perovskite Anodes in a Syngas Fed-SOFC

As the world moves to decarbonize the fossil fuel sector, transition technologies are needed that bridge the gap between natural gas power plants and more sustainable low-carbon energy sources. These newer technologies often still rely on fossil fuels but have improved energy conversion efficiencies and lower net carbon dioxide (CO2) outputs over conventional fossil fuel based electric power generation systems. In this work, we are exploring one such technology, namely the use of a syngas-fed solid oxide fuel cell (SOFC) to generate heat, electricity, steam, and captured CO2. Core to this technology is the mixed ion electron conductor deployed at the anode and cathode that catalyzes all of the relevant reactions, namely electrochemical oxidation of hydrogen (H2) and carbon monoxide (CO) at the anode, producing steam and CO2, and reduction of oxygen at the cathode.Carbon formation (coking) is normally a significant problem affecting SOFCs operating on carbon-based fuels, as it leads to a rapid decline in electrochemical performance by blocking catalytically active sites and pores with various carbon species, e.g., amorphous, graphitic, or nanotubular carbon.1 The formation of carbon species from syngas is known to occur through various mechanisms, with the Boudouard reaction (∆H= -172 kJ/mol) and the reduction of CO (∆H= -131 kJ/mol) being the most prominent.2 As such, temperature is a key parameter to optimize as it determines the propensity for carbon formation at equilibrium. In addition, the kinetics of carbon formation can be significantly reduced by introducing oxygen to the fuel gas stream in the form of O2, CO2, or H2O.3 The catalyst materials investigated here are mixed conducting perovskite oxides (La0.3Ca0.7Fe0.7Cr0.3O3- δ, LCFCr) that have been optimized and modified recently by our group, both in the as-prepared undoped form and after B-site doping with variable quantities of transition metals (M), e.g., Ni,4 forming nanoparticle (NP)-decorated ABO3-Mx surfaces. Our catalyst is highly active for H2 and CO oxidation, CO2 reduction, and O2 reduction, where it was demonstrated that the un-doped parent material can deliver a stable power density of 0.2 W/cm2 for several hundred hours with negligible performance degradation in 3% humidified H2.5 In more recent work, excellent resilience to carbon deposition for exsolved Fe-Ni@LCFCr up to 70:30 CO:CO2 was demonstrated.4 Herein, we show that minimal coke forms during exposure of these materials to dry syngas at 600oC, even under open circuit conditions.The catalysts were prepared using combustion synthesis and were characterized by XRD, SEM EDX, and TPO-MS in order to confirm morphology, crystal structure, and composition as a function of temperature and gas environment.4 Symmetrical electrolyte-supported SOFCs were constructed using our catalyst as both the anode and cathode. Catalyst layers of 1 cm2 were screen printed to a thickness of 25 µm on both sides of commercially available 130 µm thick samaria-doped ceria (SDC)-buffered scandia-stabilized zirconia (ScSZ) electrolyte, followed by sintering at 1100°C for 2 h,4 with porous metal current collectors used. The cells were mounted and tested in a Fiaxel SOFC test station with gas flow controlled by mass flow controllers.Preliminary electrochemistry experiments were conducted in 5:95 H2:N2, or 1:1 H2:CO (syngas) balanced by CO2 in a 1:2 ratio of fuel to oxidant into the anode chamber, and air into the cathode chamber at 600 oC, with performance evaluation carried out using CV, EIS and chronopotentiometry. The power density was found to be ca. 2x higher in dry H2 vs. in syngas, as expected, considering that H2 is a more active fuel vs. CO. Additionally, EIS exhibited ca. 2x higher resistance in the low frequency arc in syngas, which can be attributed to sluggish CO oxidation kinetics.4 Chronopotentiometry was performed for 20 h at 10 mA cm-2, showing a degradation rate of only 0.08 mV h-1, suspected to be primarily due to current collector delamination. Coking studies were also conducted on button cells at 600 oC in 1:1 H2:CO for 25 h at open circuit, comparing to a NiO standard that was painted on the electrolyte just next to the LCFCr-Ni working electrode. Imaging by SEM showed negligible carbon formation on the perovskite surface, supported by EDX analysis, compared to the extensive degree of coking observed at the standard. Further quantification was conducted by TPO-MS, also confirming minimal carbon formation. References Bengaard et al., Journal of Catalysis, 2002, 209, 365–384.Farshchi Tabrizi et al., Energy Conversion and Management, 2015, 103, 1065–1077.Sasaki et al., Journal of The Electrochemical Society, 2003, 150.Ansari et al., Journal of Materials Chemistry A, 2022, 10, 2280–2294.Addo et al., ECS Transactions, 2015, 66, 219–228.

EXPRESS ANALYSIS OF PROBABILISTIC CHARACTERISTICS OF WIND POWER TATIONS AS A SOURCE OF ENERGY FOR SEAWATER DESALINATION IN THE AZOV-BLACK SEA REGION OF UKRAINE

Ukraine takes part in the implementation of the European program «2´40 GW Green Hydrogen Initiative». It is planned to build 10 GW of electrolyser capacity on the territory of Ukraine for the production of «green» hydrogen using the energy of wind power stations in the Azov-Black Sea region. Territorial sea waters of Ukraine are characterized by a significant potential of offshore wind energy, which is currently developing rapidly in the world. One of the alternative options for supplying fresh water for the operation of electrolysers when powered by offshore wind power stations involves using desalinated seawater. The operation of 10 GW of electrolyser capacity will ensure the production of «green» hydrogen in the amount of 1.65 million tons per year and will require the consumption of prepared fresh water of about 24 million m3/year. Seawater desalination is an established technology that is widely used worldwide to reduce freshwater scarcity. The use of energy from wind power stations for seawater desalination is an alternative option within the scope of this Program. However, the mismatch between the random nature of wind power generation and the constant energy demand for desalination makes the integration between the two technologies all the more important. The goal of this paper is to estimate the probabilistic annual ensuring of given levels of power and volume of electricity production by wind power stations in the coastal and offshore territories of the Azov-Black Sea region of Ukraine. The probabilistic annual distributions of wind speed and energy indicators of wind power stations for a height of 100 meters were studied, the average annual wind speed of about 7.5 m/s was substantiated. An achievable value of the utilization rate of the installed capacity of wind power stations was obtained at the level of 35 %, provided that the generated energy is fully integrated into the technological schemes of water desalination. The duration of production of full and half volumes of electricity production and power generation is determined. Algorithms for calculating the probability of exceeding various required power levels and volumes of electricity production by wind power stations have been developed. Bibl. 48, Fig. 6, Tab. 4.

Optimal design of hydrogen-based storage with a hybrid renewable energy system considering economic and environmental uncertainties

Hydrogen and electricity derived from renewable sources present feasible alternative energy options for the decarbonisation of the transportation and power sectors. This study presents the utilisation of hydrogen generated from solar and wind energy resources as a clean fuel for mobility and backup storage for stationary applications under economic and environmental uncertainties. This is achieved by developing a detailed techno-economic model of an integrated system consisting of a hydrogen refuelling station and an electric power generation system using Mixed Integer Quadratic Constrained Programming (MIQCP), which is further relaxed to Mixed Integer Linear Programming (MILP). The model is implemented in the Advanced Interactive Multidimensional Modelling Software (AIMMS) and considering the inherent uncertainties in the wind resource, solar resource, costs and discount rate, the total cost of the three configurations (Hybrid PV-Wind, Standalone PV, and Standalone wind energy system) was minimised using robust optimisation technique, and the corresponding optimal sizes of the components, levelised cost of energy (LCOE), excess energy, greenhouse emission avoided, and carbon tax were evaluated. The levelised cost of the deterministic optimisation solution for all the configuration ranges between 0.0702 $/kWh to 0.0786 $/kWh, while the levelised cost of the robust optimisation solution ranges between 0.07188 $/kWh to 0.1125 $/kWh. The proposed integration has the advantages of affordable hydrogen and electricity prices, minimisation of carbon emissions and grid export of excess energy.

Techno-economic and environmental performance of a novel thermal station characterized by electric power generation recovery as by-product

As the quality of life continues to improve, the requirement for district heating is gradually growing, contributing to problems of climate change and environmental degradation. The electricity consumption and heat losses in thermal stations are significant. To address these issues, a novel self-sufficient thermal station in electric power is proposed in this paper. The techno-economic and environmental performances of the novel electricity self-sufficient thermal station under operating conditions is analyzed employing a mathematical model. The results show that the higher the temperature of the primary heating network supply water, the better the overall performance of the system. Additionally, a lower point pinch temperature difference is beneficial for improving the performance of the system. At the primary heating network supply water temperature of 100 °C and the evaporating temperature of 69 °C, the PBP obtains the minimal value of 6.53 years. The annual saving coal can reach 73.21 t and reducing CO2 emissions can reach 199.55 t. Therefore, the novel electricity self-sufficient thermal station can meet certain technical requirements for combined heating and power generation while demonstrating superior economic capability.