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The objective of this paper is to identify the most sensitive component of a turbogenerator and optimize its availability. To achieve this, we begin by conducting an initial reliability, availability, maintainability, and dependability (RAMD) analysis on each component. Subsequently, a novel stochastic model is developed to analyze the steady‐state availability of the turbogenerator, employing a Markov birth‐death process. In this model, failure and repair rates are assumed to follow an exponential distribution and are statistically independent. To optimize the proposed stochastic model, we employ four population‐based meta‐heuristic approaches: the grey wolf optimization (GWO), the dragonfly algorithm (DA), the grasshopper optimization algorithm (GOA), and the whale optimization algorithm (WOA). These algorithms are utilized to find the optimal solution by iteratively improving the availability of the turbogenerator. The performance of each algorithm is evaluated in terms of system availability and execution time, allowing us to identify the most efficient algorithm for this task. Based on the numerical results, it is evident that the WOA outperforms the GWO, GOA, and DA in terms of both system availability and execution time. [ABSTRACT FROM AUTHOR]

The final feedwater temperature is the temperature of the feedwater supplied to the boiler in the power plant applied with the Rankine cycle. In thermal power plants adopting a regenerative cycle, it is generally known that the heat transfer of the boiler is reduced, and the efficiency of the power plant is increased. However, the output of the power plant is reduced when the final feedwater temperature is increased. In this study, the net output and efficiency of the power plants depending on the final feedwater temperature under the condition of constant boiler heat transfer rate were analyzed for five cases. The results show that there is a final feedwater temperature at which the net output and the net efficiency are maximized. The additional output of the power plant obtained by increasing the final feedwater temperature has the effect of reducing CO2 emissions. If the final feed water temperature is below 308.3 °C, the net output and the final feed water temperature are proportional for all cases. When the final feedwater temperature increases by 1 °C, the net output increases by 63.02 kW and CO2 emissions are reduced by 60.52 kgCO2/h on average. [ABSTRACT FROM AUTHOR]

This research work suggests the application of predictive modeling for the Nitrogen Oxide (NOx) emissions from the 210 MW pulverized boiler that burns coal. In order to lower the NOx emissions in the flue gas, it is necessary to optimize various operational parameters during combustion, including oxygen in flue gas, various damper opening positions, air-distribution system, nozzle tilt, and the temperature of the flue gas outlet. Information gathered from variable parametric field tests was used to create an Artificial Neural Network (ANN) model. The model estimated NOx emissions based on the parameters of coal combustion. The ANN model was put to the test under full load conditions and the results of its predictions were compared to the actual values. The trained ANN with its biases and weights in the form of arithmetical equations was given as a fitness function to the weighted distance Grey Wolf Optimizer (GWO) to improve operating conditions for decreased NOx emissions. [ABSTRACT FROM AUTHOR]

Combustion optimization is an effective way to improve the efficiency of thermal power generation and reduce carbon and NOx emissions. Real-time and precise NOx emission prediction is the basis for combustion optimization control of thermal power plants. To construct an accurate NOx concentration prediction model, a novel just-in-time learning (JITL) method based on random forest (RF) is proposed in the present work. With this method, first, an improved permutation importance algorithm is proposed to extract important variables. In addition, a similarity index that incorporates temporal and spatial measures is defined to select a local training set representative of the process data. Moreover, considering the influence of model parameters on prediction performance under different working conditions, a process monitoring method based on a moving window (MW) is used to monitor the change in working conditions and guide online updating. The experimental results show that the proposed method has excellent prediction accuracy, with a coefficient of determination of 0.9319, a root-mean-square error of 3.6960 mg/m3, and an average absolute error of 2.7718 mg/m3 on the test set, making it superior to other traditional methods. [ABSTRACT FROM AUTHOR]

CO2 emissions into the atmosphere in the electricity sector in 2022 exceeded 12.4 billion t, which is 1.8 times more than in 2000. The reasons for this growth are analyzed. It is noted that a significant contribution to these emissions (75%) is made by electricity generation using coal as fuel. It has been shown that it cannot be expected that CO2 emissions will decrease in the near future as a result of the reduction in coal capacity; there is a steady increase in the world. In the 21st century, the total capacity of coal-fired thermal power plants increased approximately 1.9 times. Alternative ways to reduce greenhouse gas emissions are being considered, primarily through the construction of new, highly efficient power units with increased steam parameters and the decommissioning of obsolete equipment. Thanks to this, the structure of coal generation in the world is changing significantly: Thermal power plants with power units for super-supercritical (SSCP) steam parameters and supercritical pressure (SCP) already account for more than 47% of the total capacity of coal-fired thermal power plants. Such changes contributed to a reduction in specific greenhouse gas emissions from 466 g CO2/(kW h) in 2000 to 436 g CO2/(kW h) in 2022. In the Russian electricity sector, CO2 emissions in 2022 amounted to approximately 410 million t. Since 2000, they have grown by only 22%. The share of CO2 emissions from coal thermal power plants in Russia are estimated at 35–45% of the total amount of greenhouse gases associated with electricity production and does not exceed 0.5% of the global total due to the use of fossil fuels. Due to the low contribution of CO2 emissions by Russian coal-fired thermal power plants, reducing greenhouse gas emissions from coal-fired power generation is not so relevant in the global problem and are solved mainly by replacing coal with natural gas. The need to introduce highly efficient but expensive equipment (for example, SSCP power units) at coal-fired thermal power plants to reduce emissions greenhouse gases is not as obvious as abroad, and its implementation requires a detailed feasibility study. [ABSTRACT FROM AUTHOR]

To promote the development and application of continuous monitoring technologies for CO2 emissions from thermal power plants in China and support the establishment of a carbon emission statistics and accounting system in the country, this study analyzes the international experience in the continuous monitoring of CO2 emissions from thermal power plants using literature research, expert discussion, and technical interpretation, with a focus on the United States and the European Union. The analysis covers eight aspects: types of units applying the technology, formulation of implementation standards, measures for dealing with failures, selection of monitoring technologies, research on key technologies, support for the low-carbon development of thermal power plants, verification of monitoring reports, and evaluation of measurement accuracy. Drawing on international beneficial experience and considering the current status of continuous monitoring of CO2 emissions from thermal power plants in China, the study proposes the following suggestions: (1) formulating supporting policies and regulations while considering the characteristics of technology application and the actual situation of thermal power plants in China, (2) accelerating the improvement in technical implementation standards and specifications to enhance the guiding and supporting role of standards, (3) strengthening the statistical analysis of the measurements using existing flue gas flow meters to provide references for relevant work, (4) enhancing research on flue gas flow measurement in thermal power plants to improve the technical level of continuous monitoring of CO2 emissions, (5) promoting the application of digital technologies in the verification of monitoring reports to support closed-loop management of continuous monitoring of CO2 emissions, and (6) improving the evaluation standards system for measurement accuracy of continuous emission monitoring systems to enhance the international recognition of China’s carbon emission data.

Abstract The challenge of providing water, energy, and managing the environment is widely recognized as a significant barrier to global advancement in light of the increasing population. Based on projections, it is anticipated that the global community will encounter crises pertaining to water, energy and the environment in the foreseeable future. In this research, the application of the hybrid renewable system in a thermal power plant has been assessed based on the approach of analyzing the link between energy, water, and environment. The design of the solar system and the assessment of carbon balance during the power plant lifetime have been conducted in PVsyst application in 2022. Moreover, ReCipe environmental model has been used for assessing the effect of decrease in carbon emission on the ecosystem. The findings of the research indicate that the replacement of at least 2% of the nominal capacity of the fossil fuel power plant with the renewable one, prevents the emission of 1340.37 tons of carbon dioxide yearly. This amount equals to 371.25 m3 of reserve in fossil fuel consumption and 382.64 tons of crude oil. The results also showed that in addition to preserving natural resources, the hybrid cycle design leads to significant water demand reduction which equals to 3751 m3 with the capacity to supply underground water sources. Due to the interests of preserving water and energy resources and decreasing carbon emission in power plant industry, within the framework of nexus approach, management of energy supply by replacing resources and using water and heat recovery technologies and application of energy demand management policies based on energy efficiency and environmental implications is recommended.

Abstract The impacts of climate change, combined with the depletion of fossil fuel reserves, are forcing human civilizations to reconsider the design of electricity generation systems to gradually and extensively incorporate renewable energies. This study aims to investigate the technical and economic aspects of replacing all heavy fuel oil (HFO) and light fuel oil (LFO) thermal power plants connected to the electricity grid in southern Cameroon. The proposed renewable energy system consists of a solar photovoltaic (PV) field, a pumped hydroelectric energy storage (PHES) system, and an ultra-capacitor energy storage system. The economic and technical performance of the new renewable energy system was assessed using metrics such as total annualized project cost (TAC), loss of load probability (LOLP), and loss of power supply probability (LPSP). The Multi-Objective Bonobo Optimizer (MOBO) was used to both size the components of the new renewable energy system and choose the best location for the solar PV array. The results achieved using MOBO were superior to those obtained from other known optimization techniques. Using metaheuristics for renewable energy system sizing necessitated the creation of mathematical models of renewable energy system components and techno-economic decision criteria under MATLAB software. Based on the results for the deficit rate (LPSP) of zero, the installation of the photovoltaic field in Bafoussam had the lowest TAC of around 52.78 × 106€ when compared to the results for Yaoundé, Bamenda, Douala, and Limbe. Finally, the project profitability analysis determined that the project is financially viable when the energy produced by the renewable energy systems is sold at an average price of 0.12 €/kWh.

One of the important parameters in power system stability is frequency. The importance and difficulty of frequency control in a multi-area power system increases with the integration of several power generation sources. One of the important tasks of frequency load control is to eliminate frequency deviation error. The analysis of small signal stability using linearized model of single-area power system with different power sources is presented in this study. Power system area includes three steam turbine power plants with reheater, hydro turbine power plant with transient compensator and gas turbine power plant. To eliminate the frequency deviation that occurs due to small disturbances in the system, a load frequency controller is used. The simulation results along with the analysis of the system modes (eigenvalues analysis) show the dynamic behavior of the system due to the changes in the parameters and the participation coefficients of the power plants. The dynamic behavior of the power system is simulated using MATLAB software. [ABSTRACT FROM AUTHOR]

The challenge of providing water, energy, and managing the environment is widely recognized as a significant barrier to global advancement in light of the increasing population. Based on projections, it is anticipated that the global community will encounter crises pertaining to water, energy and the environment in the foreseeable future. In this research, the application of the hybrid renewable system in a thermal power plant has been assessed based on the approach of analyzing the link between energy, water, and environment. The design of the solar system and the assessment of carbon balance during the power plant lifetime have been conducted in PVsyst application in 2022. Moreover, ReCipe environmental model has been used for assessing the effect of decrease in carbon emission on the ecosystem. The findings of the research indicate that the replacement of at least 2% of the nominal capacity of the fossil fuel power plant with the renewable one, prevents the emission of 1340.37 tons of carbon dioxide yearly. This amount equals to 371.25 m3 of reserve in fossil fuel consumption and 382.64 tons of crude oil. The results also showed that in addition to preserving natural resources, the hybrid cycle design leads to significant water demand reduction which equals to 3751 m3 with the capacity to supply underground water sources. Due to the interests of preserving water and energy resources and decreasing carbon emission in power plant industry, within the framework of nexus approach, management of energy supply by replacing resources and using water and heat recovery technologies and application of energy demand management policies based on energy efficiency and environmental implications is recommended. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

Introduction: Cuban crude oil has a high content of ash, sulfur, asphaltenes and a high viscosity, among others, which, when subjected to the combustion process, results in corrosive effects in the heat transfer zones, reducing the useful life of the equipment. Objective: To design a procedure for the introduction of additives, which will increase the useful life of the equipment by improving the energy efficiency of the combustion process. Materials and Methods: It starts from the analysis of the composition and physical-chemical properties of Cuban crude oil and the characterization of the additive. The effectiveness of the additive is evaluated on a laboratory, pilot and industrial scale. The combustion parameters are adjusted and the efficiency of the steam generator is analyzed, with the aim of establishing the required dosage. The corresponding profit/economic cost analysis is carried out. Finally, the procedure is designed to compare with another additive if it exists. Results and Discussion: The procedure includes the determination of the chemical composition and physical-chemical properties of the crude oil used, the effect of the additive and the combustion efficiency. It contemplates not only the analysis of the use of an additive in use, but also the introduction of a new one and the comparison with it. It can be implemented in any industry that uses crude oil as fuel in the combustion process. Conclusions: The procedure provides the methodological indications for the introduction of additives that allow the improvement of the steam generator combustion process. [ABSTRACT FROM AUTHOR]

This article discusses the negative impacts of fly ash pollution near coal-fired thermal power plants in Chhattisgarh, India. It explores the effects of fly ash on vegetation and methods for controlling its spreading and disposal. The article also discusses the physico-chemical properties of fly ash and its effects on soil and plants in the vicinity of thermal power plants. It emphasizes the importance of effective management of fly ash for the environment and the role of plants in mitigating its adverse effects. The provided document consists of three research articles related to environmental pollution and its impact on plant biomass, element accumulations, and soil microbiological communities. These articles provide valuable insights into the relationship between environmental pollution and plant and soil health. [Extracted from the article]

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials 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.)

The adverse effects of thermal power plants on crop yield have not received adequate attention. Thus, this study aims to evaluate these effects systematically to fill the gap by utilizing county-level wheat yield data from North China spanning from 2005 to 2016. Our findings indicate that the presence of an additional upwind thermal power plant is associated with a 1.4% decline in wheat yield. Notably, these yield losses are more pronounced in regions characterized by lenient environmental regulations or a high density of large-scale thermal power plants. Reduced wheat yield due to thermal power plants results in a decline in social welfare. Furthermore, we confirm that air pollution emitted from thermal power plants is the primary driver behind the decline in wheat yield. [ABSTRACT FROM AUTHOR]

Thermal power generation is economical in the current scenario, but it is a water-intensive process, resulting in a high-water footprint. In this research, life cycle water use (LCWU) was assessed for three coal-based thermal power plant in India. The LCWU was found to be in the range of 2.5 to 3.5 L-kWh−1. The results of the LCWU of coal-based thermal power plants in India are higher than the global average of 1.75 L-kWh−1. In order to reduce the dependency on water, air-cooled condenser (ACC) with a novel approach of reducing temperature of air before entering into condenser is purposed using vapour absorption chillers. A 300 MW thermal power plant located in the South India region is chosen to illustrate the application of the proposed system. Initially, waste heat from flue gas is used to run a vapour absorption chiller, and finally a solar-assisted vapour compression chiller is used. Also, in order to utilize large coastal lines in India, an alternate approach of sea water cooling-based thermal power generation is investigated. A 2 MW steam turbine plant utilizing deep sea water is designed and analysed. In seawater cooling system the condenser temperature is reduced, increasing efficiency by 1.9% and power output by 133 kW. It resulted in power generation with multiple benefits, including cooling, desalinated water, and increased plant efficiency. The outcomes of this study provide information on water use in Indian thermal power plants along with its comparative assessment. A study of ACCs and seawater-cooled condensers is also an opportunity to reduce the life-cycle water use in thermal power plants in India. [ABSTRACT FROM AUTHOR]

This study introduces a data‐driven model for online fault pre‐warning in thermal power plants using incremental Gaussian mixture regression. To tackle the issue of outdated parameters in existing fault pre‐warning models, this study puts forth an incremental Gaussian mixture regression that leverages the merging of Gaussian components to reconstruct the model and enable online modelling. Due to its criticality, a forgetting factor is introduced during the merging process to efficiently manage the weight allocation between present and historical patterns, thereby guaranteeing the model's accuracy. The results of the sine function case demonstrate that the incremental Gaussian mixture regression (IGMR) model exhibits excellent pattern control performance and modelling efficiency. Furthermore, the IGMR model is employed to forecast parameter alterations in pulverizer blockages with mode switching, and experimental validation indicates that IGMR precisely anticipates parameter changes following mode switching. Compared to on‐site solutions, the pre‐warning of coal blockage has a clear advantage in advance warning. [ABSTRACT FROM AUTHOR]

This research work suggests the application of predictive modeling for the Nitrogen Oxide (NOx) emissions from the 210 MW pulverized boiler that burns coal. In order to lower the NOx emissions in the flue gas, it is necessary to optimize various operational parameters during combustion, including oxygen in flue gas, various damper opening positions, air-distribution system, nozzle tilt, and the temperature of the flue gas outlet. Information gathered from variable parametric field tests was used to create an Artificial Neural Network (ANN) model. The model estimated NOx emissions based on the parameters of coal combustion. The ANN model was put to the test under full load conditions and the results of its predictions were compared to the actual values. The trained ANN with its biases and weights in the form of arithmetical equations was given as a fitness function to the weighted distance Grey Wolf Optimizer (GWO) to improve operating conditions for decreased NOx emissions.

With the proposal of ''Carbon peaking and carbon neutrality'', Adiabatic Compressed Air Energy Storage (A-CAES) has emerged as a significant component within China's energy storage infrastructure. But its thermodynamic efficiency and economical return need yet to be raised. The present paper proposed a modified system coupling with thermal power plant to utilize the excess compression heat. Utilizing advanced transient modeling software, an A-CAES plant is modeled and validated. The operation performance of the coupled system is compared with non-coupled system, which shows that the system efficiency is raised from 54.8 % to 76.7 % and the investment return rate is improved from 9.18 % to 10.43 %.

In the proposed research article, the grey wolf optimization (GWO) technique is utilized to optimize the proportional (P) integral (I) derivative (D) (PID) controller/regulator gain parameters in three-area grid-connected power networks. The interconnected power plant covers thermal plants, hydro plants, and nuclear power plants. The proposed controller is used as a secondary controller in the power system to perform load frequency control (LFC). Under unforeseen load conditions, the system frequency deviates from the norm. To control and stabilize this oscillation, the LFC system is used. During the investigation, a step load perturbation of one percent (SLP 1%) is applied for the analysis of the thermal power plant. The response of the suggested optimization technique-designed regulator performance is equated with the genetic algorithm (GA)-tuned, particle swarm optimization (PSO)-tuned, and ant colony optimization (ACO) technique-tuned PID regulator response. The performance response is evidence that the GWO-based PID regulator provides a regulated response with minimal time-domain specification parameters (settling time, peak shoots) over other tuning methods. The effectiveness and robustness of the improved response of the suggested technique-optimized controller are verified with various load values (1%, 2%, and 10% SLP) and nominal parameter (R, Tp, and Tij) variations (± 25% & ± 50%) from its nominal value. [ABSTRACT FROM AUTHOR]

Emissions from thermal power plants have always been the central consideration for environmental protection. Existing optical sensors in thermal power plants usually measure the total mass concentration of the particulate matter (PM) by a single-wavelength laser, bearing intrinsic errors owing to the variation in particle size distribution (PSD). However, the total mass concentration alone cannot characterize all the harmful effects of the air pollution caused by the power plant. Therefore, it is necessary to measure the mass concentration and PSD simultaneously, based on which we can obtain multi-particle-size channel mass concentration. To achieve this, we designed an optical sensor based on the three-wavelength technique and tested its performance in a practical environment. Results showed that the prototype cannot only correctly measure the mass concentration of the emitted PM but also determine the mean diameter and standard deviation of the PSDs. Hence, the mass concentrations of PM10, PM2.5, and PM1 are calculated, and the air pollutants emission by a thermal power plant can be estimated comprehensively. [ABSTRACT FROM AUTHOR]

This paper studies when and under what conditions the actions undertaken by the power plants involved in China's emission trading scheme (ETS) pilot became cost effective. Based on unique plant-level panel data and the difference-in-differences strategy, we identify that an insignificant initial reduction in cost efficiency occurred at the announcement stage for power plants in the pilot provinces; however, the cost efficiency of the pilot plants increased significantly following formal policy implementation. Additionally, the by-stage treatment effects differed across the pilot provinces due to localized market and non-market variations. Localized conditions of higher marketization, stricter policy enforcement, and lower carbon dependence enhanced this positive effect. The synthetic control results confirmed this variation in the policy effects. The carbon trading pilots resulted in improved efficiency in power plants in Shanghai, Guangdong, and Tianjin during the period 2013--2017, with an associated total cost saving of approximately 29.75 million RMB. To enhance the efficacy of the ETS policy, our findings suggest that the design of the policy should consider localized external factors. [ABSTRACT FROM AUTHOR]

Measurements of radon and thoron concentrations were taken at 70 locations in and around Gandhinagar Gujarat, India. The radon concentration varied between 175 and 14,807 Bq/m3, whereas, thoron varied between 28 and 15,033 Bq/m3. Maximum concentration of radon and thoron is observed in northern and eastern part of Gandhinagar due to fly ash content of the soil discharged from the Gandhinagar thermal power station. The annual dose rate due to inhalation varied between 0.0013 and 0.1337 mSv/year, below the ICRP recommendation. High radon concentrations are also observed in dumping areas and geological structures with high seismic risk. [ABSTRACT FROM AUTHOR]

A concept has been proposed for the creation of regional liquefied natural gas (LNG) fuel complexes on the basis of thermal power plants, ensuring the expansion and reliable functioning of the gas fuel market. The concept provides for the transfer of fuel reserve systems for electric power facilities to LNG, which is produced directly at power plants, as well as the supply of LNG from power plants to regional consumers. A description of a foreign installation for extinguishing gas consumption peaks is given: the closest analogue of a power plant with an LNG fuel backup system. A comparative technical and economic analysis of projects for the construction of a fuel oil facility and an LNG backup fuel system for CHPP-22 of PAO Mosenergo showed that, with comparable capital costs, backup using LNG can provide an economic effect of up to 654 million rubles per year at 2023 prices. If there are large volumes of LNG storage, peak fuel shipments to consumers can be ensured, and the standard reserve will be restored using a liquefaction unit. Data are provided for calculating the costs and investments required to create complexes that guarantee the maintenance of standard emergency fuel reserves in the form of LNG for the CCGT-220 power unit (1778 million rubles excluding VAT). A methodology has been proposed for allocating the costs of a complex of emergency fuels, attributable to the cost of electric power and LNG sold to third-party consumers. It is shown that the relative increase in capital costs for the construction of CCGT-220 with emergency fuel in the form of LNG in relation to similar costs for a power unit with emergency diesel fuel is 1%. The cost of in-house LNG production has been assessed. Savings during the initial formation of standard emergency reserves for the power unit amounted to 72.45 million rubles. The advantage of creating a network of LNG complexes is formulated: reserve and emergency fuel reserves at thermal power plants provide a reliable fuel supply to regional markets. [ABSTRACT FROM AUTHOR]

The study deals with the possibilities of using alternative types of fuels to produce electricity. Power Plant Vojany (PPV) is a thermal power plant (TPP) in eastern Slovakia, which is part of the company Slovenské elektrárne, a. s. (SE). PPV primarily used black coal to produce electricity, which had to be imported from abroad (the Russian Federation). This activity has become inefficient both economically and environmentally, due to the high price of CO2 permits and the high emission factor of this type of fuel. PPV decided to co-combust biomass and refuse-derived fuel (RDF), which resulted in much better economic conditions due to their price, economic efficiency, and partly closed CO2 cycle. The aim of the paper is to explore the possibilities related to the production of energy in the cleanest possible way and with the least possible damage to the environment in coal thermal power plants using the example of operating Power Plant Vojany located in eastern part of Slovakia and to inspire each other for the modern transformation. For the purposes of hypothesis verification, analytical methods focused on overview studies of average fuel prices, comparisons, and the balance of fuels in connection with eliminated CO2 emissions, as well as municipal waste (MW) management in the EU and V4 countries, were used. The authors also focused on the energy recovery and combustion of MW and tracking the achieved CO2 savings in connection with the development of fuel sources in PPV. The results point to the fact that PPV is one of the power plants that could use biomass and RDF as fuel, which confirms the economic advantages of this procedure. The results confirm that the potential of RDF production in Slovakia is sufficient to ensure the operation of PPV at planned, even higher volumes of electricity production. The transformation to cleaner operation of coal thermal power plants represents a significant contribution of this study. [ABSTRACT FROM AUTHOR]

The combustion heat measurement is a classic physical chemistry experiment. In this case, the combustion heat measurement is correlated with the electric power generation from the combustion of the agricultural and forestry waste. The contents of the classic experiment are modified appropriately. During performance of the newly designed experiment, students’ understanding of the significance of combustion heat measurements for the safety of the power plant operation, as well as the agricultural and forestry waste combustion power generation for serving “agriculture, rural area, and farmers”, rural revitalization and “dual carbon” strategy can be improved. The students’ ability to apply what they learn from physical chemistry and laboratory courses can be enhanced. It can stimulate students’ interest in learning, guides students to care more about national energy security, environmental protection, sustainable development and people’s life and health. The modified experiment can greatly improve the students’ ability and quality. [ABSTRACT FROM AUTHOR]

Increasing the energy efficiency of thermal power plants operating according to the Rankine cycle is one of the priority tasks of the Russian energy sector. Despite a significant amount of scientific research, the efficiency of installations of this type still remains low. As a technological solution to increase their efficiency, the authors consider a modernized Rankine cycle in which an aqueous solution of lithium bromide is used as a working fluid, the condensation process of exhaust steam after the turbine is replaced by the process of its absorption, and the second working fluid is an absorbent. The features of the functioning of such a cycle are outlined, and the methodology for its calculation is presented. Studies have shown that the use of lithium bromide solution can reduce the steam pressure after the turbine and increase the useful heat drop as well as the degree of cycle filling. In addition, when the heat of the solution returned from the boiler is regenerated, the average temperature of the heat supply to the cycle increases, which also increases its thermal efficiency compared to the traditional circuit. The energy efficiency of the modernized cycle was analyzed and compared with the traditional Rankine cycle on water vapor. Calculations have shown that the use of a modernized cycle allows increasing thermal efficiency by an average of 1–2% compared to the traditional solution. The indicators characteristic of both steam power and absorption cycles were studied, and graphical dependences of efficiency on the main parameters were derived. The economic effect of using the modernized scheme is to reduce fuel consumption and emissions of harmful substances into the atmosphere in proportion to the reduction in fuel consumption. [ABSTRACT FROM AUTHOR]

Copyright of Power Generation Technology is the property of Power Generation Technology Editorial Office 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.)

The work is devoted to the development of a thermal scheme for the conversion of a cogeneration power plant to threegeneration with the production of hydrogen as a new product. The purpose of the work is to assess the possibility and potential of hydrogen production from MSW at the existing thermal power plants of St. Petersburg. To achieve this goal, it is necessary to develop a methodology for selecting the site of an existing thermal power plant in order to integrate a hydrogen production complex by the MSW gasification method, as well as a methodology for estimating the amount of hydrogen that can potentially be obtained from a given amount of MSW. The research methods include simulation of the thermal circuit of a steam power plant in the United Cycle program. The paper proposes an algorithm for selecting the site of an operating thermal power plant for the integration of a complex for the production of hydrogen by the method of MSW gasification. The algorithm can be applied to any subjects of the Russian Federation, and its relevance is confirmed by strategic documents. Potential locations for the new TPP are being considered in the territories of TPP-21 and TPP-22, which have the necessary resources and good infrastructure. As a result of the study, the site of TPP-22 was selected as the most suitable for the placement of new facilities. A new thermal scheme of a threegeneration power plant has been developed, including a hydrogen generation unit by the MSW gasification method. This allows the production of hydrogen in parallel with the production of electricity and heat. The efficiency evaluation criterion is the fuel heat utilization factor (FHUF). Regardless of the hydrogen content in the generated synthesis gas, the integration of the synthesis gas cooler into the thermal circuit of the TPP leads to an increase in the FHUF and an additional energy effect. This scheme increases the efficiency of existing TPP plants, regardless of the morphological composition of municipal solid waste. [ABSTRACT FROM AUTHOR]

With the global desire for decarbonization, hydrogen production should become one of the dynamically developing areas of energy resource processing. For CHPP-21 of TGC-1, the possibility of integrating and operating of a methane steam reforming unit to switch the plant from cogeneration to trigeneration production was considered. CHPP-21 includes 5 steam turbines T-100/120-130-3. A basic thermal circuit of a trigeneration power plant was developed. The impact of the transfer of a thermal power plant from cogeneration to trigeneration on its characteristic operating modes was assessed. In the winter mode with low heating loads, fuel savings when integrating the reforming unit into the CHPP amounted to 2.5%. The coefficient of fuel heat utilization increased from 78.61% to 80.63%. In summer mode, fuel economy was 13.8%. The coefficient of fuel heat utilization increased from 62.26% to 72.25%. [ABSTRACT FROM AUTHOR]

With the rapidly increasing world population and the need for industrialization, energy supply has become an important global problem. A significant part of the world's energy needs is provided by fossil fuels. About half of all global coal deposits are low-quality coals, including lignite. Karapınar/Konya, also the study area, has Turkiye's second richest lignite reserve. The region's lignite reserve can be used in thermal power plants for electricity generation in terms of its nature and the amount is an important opportunity to meet the energy demand for both region and country. The region contains many sinkholes, and the potential for the formation of new sinkholes makes the site selection for thermal power plants in the region an even more strategic decision. This study aims to propose the most suitable thermal power plant site for the region by using Multi-Criteria Decision Making methods and Geographic Information Systems in an integrated way. Within the scope of the study, a total of twelve sub-criteria were taken into consideration under the main criteria of Geological, Economic and Environmental. The Best–Worst Method was applied to determine the criteria weights, and by using the weights, a suitability map for the thermal power plant installation site was produced and candidate regions were determined. TOPSIS was applied to determine the most suitable location among the candidate regions. The Candidate Region in the easternmost part of Karapinar district was chosen as the most suitable site for the thermal power plant installation. [ABSTRACT FROM AUTHOR]

Carbon emissions from thermal power plants (TPPs) are a significant source of anthropogenic carbon and a priority for carbon reduction efforts. The accurate estimating of carbon emissions from TPPs is essential research in the field of carbon reduction. In this study, we take TPPs located in the United States as examples to discuss the relationship between the thermal characteristics of the power plant and its annual carbon emissions. Our data consists of land surface temperature (LST) product generated from Landsat 8 thermal data, LST product from ERA5-Land reanalysis dataset, and carbon emission data reported by the U.S. Energy Information Administration (EIA). Based on pertinent research of urban heat islands, we propose the concept of thermal characteristic index (TCI), which can provide a quantitative description of power plant thermal characteristics. Furthermore, we convert TCI to annual thermal characteristic index (A-TCI) by annual end-point interpolation and Simpson integration of the TCI series to match the annual carbon emission data and then establish a TCI-based annual carbon emission estimation model (TACEE-Model). Using the TACEE-Model, we predict the annual carbon emission values and evaluate the model’s performance. Experimental results indicate that the TACEE-Model exhibits great predictive capability, with the mean absolute percentage error (MAPE) of 0.0325, and the average prediction percentage error of 3.24%. The application of annual end-point interpolation and Simpson integration can significantly enhance the model’s prediction accuracy, resulting in a 51.42% reduction in MAPE. Overall, this research presents a new method for verifying annual carbon emissions from TPPs, which can contribute to the supervisory oversight of carbon emission reduction from TPPs.

The output of power unit No 2 of the Belarusian NPP to the level of neutron power development of 100 % of the nominal level has changed the structure of generation of the Unified Energy System (UES) of Belarus. At the current loads of the inter-heating period of 2023, the share of a nuclear power plant with two power units operating at full capacity in the daily generation structure of the Republic is about 50 %. In order to balance the UES of Belarus during the operation of two power units of a nuclear power plant at night, the application of adjustment regulatory measures that exceed the available capabilities is required. The almost complete use of the adjusting range of the CHP will forcibly cause, on a larger scale, to the shutdown of the blocks during the load failures at night, followed by the start-up from the non-cooled and hot statuses. These operating modes of generating equipment are inevitable in the current conditions of the electricity market, which has led to the emergence of most complex tasks to assess the economic and technical efficiency of involving or another equipment of power plants in such modes. The paper proposes an approach to solving the problem of achieving an effective combination of reliability and efficiency of energy systems on the example of gas turbines and CCGT power units. A generalized desirability function has been obtained, which includes a number of parameters for choosing a rational relationship and mutual influence between the reliability and efficiency of electricity production with the participation of thermal power plant equipment in regulating the daily load schedule. The proposed mathematical model is an effective means of analyzing the suitability of equipment for use in the required operating modes.

In optimizing the vibrodiagnostics of thermal power plants, a mathematical model was developed and used to increase the power plants’ safety and operational characteristics. The choice of diagnostic condition parameters of the components was made based on optimization characteristics that affect the accuracy of the solution and operational readiness of the thermal power plant. The research aimed to develop a universal model by analyzing more optimized vibrodiagnostics of the turbogenerator, which achieves high operational reliability, high safety, an extension of service life, an extension of working life, a reduction of overhaul time, etc. The application of the model represents the concept of optimization with the checking of condition parameters, which is applied to turbogenerator assemblies that have a continuous change of condition parameters as a function of the monitoring time, for which the functional dependence between the intensity of the parameter change and the operating time can be determined.

The approach to solving the applied problem of modernization of the 300 MW series power units produced by JSC "Ukrainian Energy Machines" by converting them from supercritical to ultra-supercritical steam parameters, provided that regenerative feed water heating system is preserved as much as possible, which will lead to an increase in the energy efficiency of the TPP with minimal conversion, is analyzed in the paper. The conversion of the K-300-240-2 power unit to the parameters of fresh steam 650 °C/30 MPa and intermediate superheated steam 650 °C/7 MPa, determined as optimal as a result of previous studies, can be carried out by completely replacing the high-pressure cylinder of the existing unit for a new high-pressure cylinder with ultra-supercritical steam parameters and superstructure with an additional intermediate-pressure cylinder while fully preserving the parameters and designs of the intermediate- and low-pressure output parts. Two options for modernization of the 300 MW series power unit thermal circuit structure were considered, and the scale of conversion of the regenerative feed water heating system was evaluated. In the first option of the thermal scheme, the 1st steam selection is organized from the cold threads of the modernized high-pressure cylinder with ultra-supercritical steam parameters, and the 2nd one – from the cold threads of the additional intermediate-pressure cylinder. In this case, two high-pressure heaters and a turbo drive of the feed pump are subject to replacement. The disadvantage of this option is that due to a significant increase in steam parameters, it is impossible to choose high-pressure heaters from the existing model range, and a new design must be developed. The electrical efficiency for this modernization option increases from 36.5% (the initial thermal circuit of the K-300-240-2 turbine) to 42.5%. In the second option, it is proposed to install an additional turbine with a capacity of 3 MW, to the input of which a steam from cold threads of the high-pressure cylinder with ultra-supercritical steam parameters is supplied with a loss equal to the sum of the 1st and 2nd selections of the original version of the turbine, on the same shaft with a turbo drive of the feed pump for the sake of preserving the existing high-pressure heater. The steam from the additional turbine selections goes to high-pressure heaters HPH9 and HPH8 with parameters corresponding to the output data of the existing turbine. Taking this into account, high-pressure heaters will not be replaceable. In addition, the power of the additional turbine is sufficient to ensure the operation of the feed pump together with the turbo drive of the feed pump to obtain a water pressure of 34 MPa. In view of this, the turbo drive of the feed pump also remains unchanged, except for the additional turbine installation. The electrical efficiency for the second option of the modernization scheme of the K-300-240-2 power unit is 42.4%. It was determined that the payback period of the modernization according to the first option is 5 years, taking into account the modernization of the boiler unit, and according to the second one – 4.5 years. It is proposed to choose the option of the thermal scheme with an additional turbine, since in this case it is possible to modernize the K-300-240-2 power unit with the maximum possible preservation of the regenerative feed water heating system while increasing its energy efficiency by almost 14%.

AbstractThe lifespan of the European hare (Lepus europaeus P.) is affected by a number of negative factors, including pollutants. In this paper, the individual and joint influence of age and habitat (elevation and distance from the thermal power plant - TPP) on pathomorphological findings of hares shot during three hunting seasons was investigated. Pathomorphological changes were found in 95.12% of hares. In hares up to 1 year of age, the changes were predominant in the lungs, and in older hares, in the kidneys. Degenerative changes in kidneys and liver and inflammatory changes in kidneys and lungs were considered important most in discussing the influence of chemical pollution. The proximity of TPP influenced the type of changes in the liver. A significant joint effect of age and elevation on the type of changes in the lungs of adult hares and on the heart of young hares was found. Elevation and distance from TPP had a joint effect on the occurrence of changes in the lungs, intestines, and heart in hares from the field farther from TPP. The results indicate that the hares were highly exposed to chemical pollutants that may affect their immunity, and lifespan.

The final feedwater temperature is the temperature of the feedwater supplied to the boiler in the power plant applied with the Rankine cycle. In thermal power plants adopting a regenerative cycle, it is generally known that the heat transfer of the boiler is reduced, and the efficiency of the power plant is increased. However, the output of the power plant is reduced when the final feedwater temperature is increased. In this study, the net output and efficiency of the power plants depending on the final feedwater temperature under the condition of constant boiler heat transfer rate were analyzed for five cases. The results show that there is a final feedwater temperature at which the net output and the net efficiency are maximized. The additional output of the power plant obtained by increasing the final feedwater temperature has the effect of reducing CO2 emissions. If the final feed water temperature is below 308.3 °C, the net output and the final feed water temperature are proportional for all cases. When the final feedwater temperature increases by 1 °C, the net output increases by 63.02 kW and CO2 emissions are reduced by 60.52 kgCO2/h on average.

Combustion optimization is an effective way to improve the efficiency of thermal power generation and reduce carbon and NOx emissions. Real-time and precise NOx emission prediction is the basis for combustion optimization control of thermal power plants. To construct an accurate NOx concentration prediction model, a novel just-in-time learning (JITL) method based on random forest (RF) is proposed in the present work. With this method, first, an improved permutation importance algorithm is proposed to extract important variables. In addition, a similarity index that incorporates temporal and spatial measures is defined to select a local training set representative of the process data. Moreover, considering the influence of model parameters on prediction performance under different working conditions, a process monitoring method based on a moving window (MW) is used to monitor the change in working conditions and guide online updating. The experimental results show that the proposed method has excellent prediction accuracy, with a coefficient of determination of 0.9319, a root-mean-square error of 3.6960 mg/m3, and an average absolute error of 2.7718 mg/m3 on the test set, making it superior to other traditional methods.

In this paper, the mechanical properties of various zones of the welded joints of a heat-resistant steel 15Kh1M1F in different states (in the initial state, after an operation on the main steam piping of a thermal power plant (TPP) for 23 years) were determined, and the fracture surfaces were analyzed using scanning electron microscopy (SEM) images. The effect of hydrogen electrolytic charging on mechanical behavior and fracture mechanism was also studied. The long-term operation of welds resulted in a higher degradation degree of the weld metal compared to the base one, indicated by the deterioration of mechanical properties: decrease in hardness, strength characteristics, and reduction in area, which was accompanied by an atypical increase in elongation at fracture. All studied zones of the operated welded joints were characterized by higher hydrogen content, 2.5–3 times higher than that in the initial state. Additional hydrogen charging of the weld joint metal led to a decrease in the strength and ductility characteristics, more significantly for the operated weld compared with the non-operated one. This justified the possibility of using short-term tests of hydrogenated WM in the air to assess the degree of its damage during operation on a steam piping. [ABSTRACT FROM AUTHOR]

In order to explore potential value of explosively growing data in thermal power unit, this paper proposes a big data mining method based on Hadoop-based Spark cluster-computing framework and algorithms. Firstly, positive and negative balance methods are used to accurately obtain actual net coal consumption, and maximum information coefficient method is used to select all parameters related to optimization objectives. Then, Spark-based Mini-Batch K-means algorithm and Elbow method are constructed to divide whole operating modes. After that, all data are discretized and mapped to corresponding intervals by using Spark-based Elbow method and Mini-Batch K-means algorithm. Finally, Spark-based parallel FP-growth algorithm is used to deeply mine the potential relationships and laws. To verify the proposed method, a 350-MW thermal power unit is taken as a study case. The important conclusions are as follows: (1) the proposed Spark-based Mini-Batch K-means algorithm reduces the calculation time by 57.11% compared with Mini-Batch K-means algorithm, and 85.61% calculation time compared with K-means algorithm. The proposed Spark-based FP-growth algorithm reduces computational time by 32.8% compared with FP-growth algorithm. (2) Strong association rules of whole operating modes are mined, and operating optimization guidance schemes for important parameters are obtained. Take operating mode 1 as an example: if the optimal result can be reasonably applied, it can save 2.942 g coal per kilowatt hour. (3) Besides, we have found out some other potential relationships among parameters, which have important reference value for on-site operators to analyze economy of the thermal power unit. [ABSTRACT FROM AUTHOR]