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The efficient recovery of the waste heat from the industrial sector can represent an essential step in global energy saving, with the proper usage of other on-grid power resources available for specific high-energy consumers. A simple, low–cost energy conversion system was tested here to recover a part of the waste heat dissipated by a gasoline engine's exhaust pipe under the car's stationary testing mode at temperatures around 80 – 100 oC. The main components of this system were a copper–made thermal collector, a commercial thermoelectric energy generator (TEG) module TEC1 – 12706 and a pin-fin heat sink under natural air convection cooling. Under the open-circuit test, heat transfer rates between 4.54 W and 5.56 W were evacuated by the heat sink. A DC electronic load RL was connected at the TEG outputs, and voltage values between 0.566 V and 1.242 V were recorded for output power values between 0.03 W and 0.16 W when RL was modified from 1 Ω to 10 Ω.

To achieve the clean energy target set by various countries and states for 2030, it is crucial to assess Carbon Emission Flow (CEF) accurately across the entire energy supply chain. This paper introduces an innovative approach employing artificial intelligence (AI) techniques to calculate both direct (Scope 1) and indirect (Scope 2) CEF, encompassing power generation, transmission, and end-user consumption of radial and loop networks. While direct emissions from connected generators can be measured using power generation data, heat rates, and fuel types, indirect emissions from imported/exported power require AI algorithms analyzing historical and real-time data. CEF for a customer or any entity is the amount of CO2 generated from power sources for that customer or entity. Our methodology computes the total (both direct and indirect) and locational marginal emission (LME) for diverse energy mixes at each node and load in the power network. This approach provides precise location specific CEF data, allowing identification of nodes with varying carbon intensity. By understanding the emissions landscape, policymakers can develop targeted strategies, facilitating the reduction of carbon emissions and guiding future taxation policies. This innovative AI-driven framework enhances our ability to transition towards a sustainable energy future while meeting clean energy goals.

Repowering of old steam power plants is a viable solution to increase power and improve efficiency. This study investigates the feasibility of feed water heating repowering for the Neka steam power plant by considering the influences of steam mass flow rate on the condenser performance and the heat rate of the new cycle. Energy and exergy analyses were conducted using the first and second laws of thermodynamics and heat transfer relations in each scheme. The effect of increasing the steam mass flow rate on the performance of the condenser and the cycle was also investigated. The repowered cycle was simulated using Thermoflow software, and the results were validated with small errors. The results showed that replacing low and high-pressure heaters with new heat exchangers increased the power of the steam unit and the repowered cycle, energy, and exergy efficiencies by 15.7%, 49.3%, 5.93%, and 2.17%, respectively. Although the condenser pressure increased by 19 millibars, leading to a 0.63% increase in the heat rate, the total heat rate of the repowered cycle improved by 4.62%. Overall, the findings demonstrate that feed water heating repowering can be an effective strategy to increase the efficiency and power of conventional steam power plants. [ABSTRACT FROM AUTHOR]

In India it has become a major challenging task in majority of thermal power stations to maintain heat rate as per design norms due to problems associated with coal quality and constraints in operation and maintenance practices. Heat rate refers to the amount of heat required to generate one unit of power which mainly depends upon coal quality. Boiler efficiency and heat rate are mainly influenced by key quality parameters of the coal that is ash, moisture, volatile matter, net calorific value of coal, ratio of fixed carbon to volatile matter and grindability of coal. In this research study an effort is being made to improve coal quality by using bio-extracts derived from leaves of citrus limon in combination with lower concentrations of Ethylene Diamine Tetra Acetic Acid (EDTA) and compare boiler efficiency/heat rate with raw and beneficiated coals. Phyto extract derived from citrus limon is effective in demineralizing Aluminium and Pyrite minerals in coal and EDTA is successful for removal of Calcium and Magnesium mineral components of coal and hence calorific value of coal is increased. Results suggesting that usage beneficiated coals improving the boiler efficiency and reducing the heat rate of the thermal unit there by crores of rupee can be saved. [ABSTRACT FROM AUTHOR]

The magnetic outcomes are frequently implemented for assessing fluid specifications around stretching magnetized surfaces and energy producing technology of thermodynamics. Magnetohydrodynamic reactors and magneto-hydrodynamic generators are two primary methods for producing magnetic flux through ionized fluids along a warmed and magnetized stretched surface. The desired outcomes of the current work are to investigate magnetic flux and heat transmission in the presence of convective boundary conditions using an electrically-conducting fluid over a stretchable cylinder. Most of the parameters are considered in the discussion with intensity and variance due to time dependent methodology. The suggested fluctuating dynamic computational framework is formulated for associated forms of coupled model under boundary variables. The appropriate non-dimensional variables are used to transform the complicated mathematical expression into a non-dimensional representation. To make the non-dimensional representation easier to work for efficient statistical calculations, it is reduced further. Later, for a variety of variables, significant computations are performed via the implicit finite difference methodology. The main finding of current communication is to explore the prominent slip effect in temperatures for every Biot number around all positions. From a physical standpoint, the phenomenon was predictable since surface heat flux is employed as sporting source to increase heat transmission in electric-conducting fluids. For every possible angle, the field of magnetism increases with minimal intensity of surface heat flux. Since, magnetizing functions referred to as an insulating layer that diminishes high temperatures across surfaces and fluids.

Each of Units 1-4 SLA PGU has a capacity of 400 MW and seven feedwater heaters, namely three lowpressure feedwater heaters (LPH 1, 2, and 3), a deaerator, and three high-pressure feedwater heaters (HPH 5, 6, and 7). HPH 5 in Unit 2 has experienced 30% tube plugging, which is equivalent to 480 out of 1579 tubes. Plugging is expected to reduce the performance of HPH. If the plugging exceeds the maximum limit, the HPH needs to be retubed to restore equipment reliability. Furthermore, a comparison of the performance of HPH 5 was calculated with plugging variations of 0%, 22%, and 30% when the unit was at full load. The calculation results of terminal temperature difference (TTD), drain cooler approach (DCA), and log mean temperature difference (LMTD) showed an increase with the increase in plugging in HPH. Meanwhile, the calculation of heat rate and effectiveness showed a decrease caused by the additional plugging in the HPH. The largest heat transfer occurs in the condensing zone of the HPH, where the value is around 80% to 85% of the total heat transfer that occurs. All calculations of the relationship between performance parameters and HPH plugging variations have an R-square value of more than 0.67, indicating a strong relationship. [ABSTRACT FROM AUTHOR]

The assessment of a Coal-Fired Power Plant (CFPP) performance is an intricate process that involves the determination of Heat Rate (HR) deviations of current operational parameters from baseline or target values. This study focuses on HR deviations of a CFPP based on the Applicable Coal Price (ACP), and the influence of the ACP price on daily losses or gains are thoroughly analyzed for key performance parameters for three fixed ACP of RM12, 18, and 24 per GJ. This paper mainly investigates key parameters and related equipment that significantly affect the HR of the CFPP and ranks the parameters affecting HR from most significant to least significant. The baseline or target values are obtained from the plant commissioning manuals and the Performance Guarantee Test (PGT). Actual real-life operational data from a 700MWn CFPP is utilized to improve the accuracy and confidence levels of the results obtained. It was found that at the nominal operating baseload, the most significant negative HR deviation is for the Rotary Air Heater (RAH) gas exit temperature with a negative HR deviation of -137.9 kJ/kWh leading to an annual loss of RM17.6 million at ACP of RM24/GJ while the superheater and reheater spray flows are contributing least to the HR deviation. This analysis highlighting the impact of key parameters affecting the performance enables plant operations and maintenance teams to focus on such parameters to mitigate losses. [ABSTRACT FROM AUTHOR]

Conceptual and design studies on 25 MW Northen Gorontalo steam based power plant are carried out under the existing comissioning data at four different load. The urgency of this study is related with supporting the prevention of greenhouse gass emission and completing indonesian power plant energy map. This observation conducted by simulating those condition in Gatecycle software and analyzing the output parameter to determine the power plant performance specifically heat rate, heat transfer duty, efficiency, power generated and fuel consumption.The study outcomes shows that heat rate at 50% TMCR was increased as much as 50 kcal/kwh as the load ramped down indicating power plant requires more energy to generate similar amount of power. While the fuel consumption, power, and efficiency proportionally werer increased as the power plant load ramping up. Comparing thirteen equipments heat transfer, condenser was conducting the highest heat transfer duty followed by boiler and first stage of superheater.

Efficiency-Centered Maintenance (ECM) models are vital in the industry since they increase the overall efficiency of the system and the availability of assets, considerably reducing polluting emissions and operating costs. Because of this, it has been tried to quantify the potential of ECM models in improving power generation systems. This paper presents an ECM model to recover the performance of a gas turbine that has suffered performance degradation due to exposure to fouling and variations in the compressor inlet air temperature. A strategy has been designed and implemented in order to define and schedule activities that, economically and energetically justified, have restored the performance of a simple Brayton cycle power generation facility. The net power output and the Heat Rate have been the performance indicators selected for monitoring the energetic condition of the gas turbine. Similarly, the availability and the mean time between interventions have been maintenance indicators. The results indicate that net power and availability have increased by 5%, the Heat Rate has decreased by 2%, and the mean time between interventions has increased by 5.7 times. The power degradation rate has been reduced from 9% to 1%, ending with an annual degradation of 7.4%. With the results obtained, it has been confirmed that the ECM applied to power cycles increases the system's operational efficiency, reducing costs and polluting emissions. [ABSTRACT FROM AUTHOR]

[Introduction] The heater’s terminal temperature difference is one of the main reasons that affect the heat economy of the unit. It has great significance to accurately and quantitatively calculate the effect of heater’s terminal temperature difference on heat economy. [Method] A 660 MW unit was taken as the research object, the equivalent heat drop method was used to calculate the effect of the heater’s terminal temperature difference on the heat rate under the four operating conditions of THA, 80% THA, 60% THA and 40% THA. The influence of the terminal temperature difference of the same stage heater on the heat rate under different working conditions and its changing law were analyzed. [Result] The results showed that the terminal temperature difference of the last stage high pressure heater and No.2 low pressure heater have a greater influence on the heat rate under various operating conditions. As the output of the unit increases, the effect of the terminal temperature difference of the same stage of high pressure heater on the heat rate gradually becomes larger, and the effect of the terminal temperature difference of the same stage of low pressure heater on the heat rate gradually becomes smaller. [Conclusion] The research results are helpful for guiding the actual operation of the unit and improving the thermal economy of the unit.

Evaluating Coal-Fired Power Plant (CFPP) performance is a complex process involving the determination of the turbine cycle Heat Rate (TCHR). This study focuses on determining the TCHR by developing a mathematical model. The model, which incorporates economic analysis of the plant, is developed using energy and mass balance relationships of the turbine cycle, validated using plant commissioning data from a 700MWn CFPP located in Perak, Malaysia. Actual plant data from a 700MWn CFPP is utilized to improve the accuracy and increase the confidence of the results of this study. It was found that at the nominal operating load of 729MWg, there is a Heat Rate (HR) deviation of -1,135 kJ/kWh, leading to daily losses of RM240,447 or USD 60,112. Furthermore, it is possible to utilize the developed model at lower loads as the plant is now being used to operate on "cyclic" loads. The daily losses at a lower load of 431MWg are RM125,767 or USD31,442. Thus, the model is able to compare the plant HR at various loads against commissioning data, and economic analysis is able to be carried out effectively. Valuable information for plant operations and performance engineers could be obtained using this model to determine plant HR. [ABSTRACT FROM AUTHOR]

The current problems of strategic goal-setting for the development of thermal power plants (TPPs) as the main sector of the electric power industry in Russia are considered. The article presents the results from studies of the possible scale and conditions of the technological transformation of Russia's thermal power industry that will make it possible to achieve the target indicators of the Energy Strategy to reduce the average TPP heat rate through improving the utilization of the capacity of existing power plants and implementing investment decisions on replacing the existing TPPs and constructing new ones based on state-of-the-art technologies. For this purpose, alternative cases of power plant development in the Unified Power System (UPS) of Russia, which differ from one another in the amounts and technological structure of the required capacity additions at TPPs and take into account the current plans for the development of nonfossil types of power plants, have been prepared. In each case, the dynamics of changes in the generating capacity structure and electricity production mix in the UPS of Russia, the demand for different kinds of fuel, and the amount of required capital investments are determined. The incremental characteristics of the TPP energy efficiency improvement are estimated according to the necessary volumes of capacity renewal and the corresponding capital requirements. Interrelations between the scales of technological renewal of the thermal power sector, the volumes of the required revenue gained by TPPs, and the electricity generation sector as a whole are studied with the use of financial and economic models. The price consequences from implementation of various TPP heat rate decreasing scenarios differing from one another in intensity are determined. It is shown that the implementation of an intense investment program for technologically restructuring the thermal power sector to achieve the target indicators of the Energy Strategy will not lead to a sharp and constant increase in the price burden provided that the policy for restraining the growth of gas prices to an extent not higher than the inflation rate is retained, and provided that measures are taken to rapidly decrease, within the nearest 5–7 years, the cost of new equipment for TPPs serially produced in Russia, primarily that based on high- and medium capacity gas turbines. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the acute physiological response to aerobic short-interval training (AESIT) at various high-intensity running speeds. A minor anaerobic glycolytic energy supply was aimed to mimic the characteristics of slow continuous runs. Methods: Eight trained male runners (maximal oxygen uptake [VO2max] 55.5 ± 3.3 mL • kg-1 • min-1) performed an incremental treadmill exercise test (increments: 0.75 km • h-1 • min-1). Two lactate turn points (LTP1, LTP2) were determined. Subsequently, 3 randomly assigned AESIT sessions with high-intensity running-speed intervals were performed at speeds close to the speed (v) at VO2max (vVO2max) to create mean intensities of 50%, 55%, and 60% of vLTP,. AESIT sessions lasted 30 min and consisted of 10-s work phases, alternated by 20-s passive recovery phases. Results: To produce mean velocities of 50%, 55%, and 60% of vLTP,, running speeds were calculated as 18.6 ± 0.7 km/h (93.4% vVO2max), 20.2 ± 0.6 km/h (101.9% vV02max), and 22.3 ± 0.7 km/h (111 .0% vVO2max), which gave a mean blood lactate concentration (La) of 1.09 ± 0.31 mmol/L, 1.57 ± 0.52 mmol/L, and 2.09 ± 0.99 mmol/L, respectively. La at 50% of vLTP, was not significantly different from La at vLTP, (P = .8894). Mean VO2 was found at 54.0%, 58.5%, and 64.0% of VO2max, while at the end of the sessions VO2 rose to 71.1%, 80.4%, and 85.6% of VO2max, respectively. Conclusion: The results showed that AESIT with 10-s work phases alternating with 20 s of passive rest and a running speed close to vVO2max gave a systemic aerobic metabolic profile similar to slow continuous runs. [ABSTRACT FROM AUTHOR]

A cyclone is widely used in the industrial world for the particle separation process. Many geometrical and operational parameters affect the cyclone separator performance. The main aim of the present study is to investigate the effect of the position of the vortex limiter and the insertion of the metal rod on the heat transfer, flow field, and cyclone performance using the computational fluid dynamics (CFD) method. Vortex limiter position varies among 160 mm, 320 mm, and 480 mm. In this work, the Reynolds stress model (RSM) is used to simulate the flow, and the Eulerian-Lagrangian approach is employed to predict the movement of particles in the cyclone. Simulation results show that the insertion of a metal rod increases the heat rate and collection efficiency by about 22% and 13%, respectively. The results also confirm that the vortex limiter position is proven to affect the performance of cyclone significantly. Unlabelled Image • Effect of Vortex Limiter Position is successfully investigated. • Effect of Insertion of Metal Rod is successfully explored. • Characteristics of Heat Transfer and Cyclone Separator Performance is successfully improved. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power 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 influence of ambient temperature and moisture content on the performance of Transcorp Power Plant, Ughelli, Delta State, Nigeria was investigated with the aid of a digital psychrometer. The simulation was done using codes developed on MATLAB R2017a and the results show that compressor power consumption increased by 1.65% for 0.7% rise in temperature, and 0.50% for 71.4% rise in moisture content. The specific fuel consumption also increased with increase in temperature where a 1.71% rise in ambient temperature resulted in a 0.15% rise in specific fuel consumption but it decreased by 0.49% for a 41.7% rise in moisture content. A 1.62% rise in temperature led to a 0.13% drop in net power output and a 29.4% rise in moisture content resulted in a 0.48% drop in net power output. Thus gas turbine plant operates optimally in areas with low ambient temperatures and high moisture content. [ABSTRACT FROM AUTHOR]

Soil samples must usually be stored for a time between collection and measurements of microbial metabolic properties. However, little is known about the influence of storage conditions on microbial metabolism when studied by calorespirometry. Calorespirometry measures the heat rate and the CO2 rate of microbial metabolism, where the ratio of heat and CO2 released, the calorespirometric ratio, informs about the nature of substrates being used by microorganisms. Application to soil microbiology is very recent, and little is known about the influence of the common soil preparation practices between collection and analysis on the calorespirometric measurements. For these reasons, the effect of storage at 4 °C on the microbial metabolism was determined by calorespirometry. Results show CO2 production rate decreases with storage time while the evolution of metabolic heat rate is more stable. The calorespirometric ratio increases with storage time in soil samples with organic matter characterized by lower carbohydrate contribution to the total carbon and higher aromaticity and is unaffected in soil samples with lower carbohydrates in the organic matter and higher aromaticity. Therefore, the calorespirometric ratio values may vary for the same soil sample, such that the soil organic matter properties, as well as the time stored at 4 °C, must be considered in interpreting calorespirometric data on soils.

Abstract In order to cater for fluctuating energy demand, power plants are designed either as base power plant or peak power plant. The advantage of base power plant is that due to its constant power generation, the power plant has a higher efficiency. To optimize and design a power plant, many previous study has been conducted. Among the studies, Power Pinch tool named Electric System Cascade Analysis (ESCA) was applied to design an optimal power system. ESCA analysis is conducted by assuming that the power plant generates constant power as it is more efficient. However, further analysis using ESCA shows that with a minimal power plant capacity would result in a trade-off that the energy storage system would be larger and leads to higher energy charging and discharging tendency (result in higher energy lost). Considering the time change of heat rate with the corresponding load factor, this study incorporates new algorithm for flexible power generation into the existing ESCA methodology. To validate the new algorithm, an off-grid distributed energy generation system is mathematically modelled and solved. The result from the new algorithm is compared with that of the mathematical model. The comparison of optimal generator capacity shows a difference of 5.71%. The similarity of the result hence validates that the new algorithm is suitable. [ABSTRACT FROM AUTHOR]

Flow loss in superplasticized systems has been mainly explained in qualitative and comparative ways over the past years. This is due to the intrinsic complexity of the underlying mechanism involving a change in the agglomeration degree as a result of cement hydration. The lack of robust and reliable experimental methodologies must have additionally discouraged researchers from attempting to understand the phenomena of flow loss in quantitative terms. Thanks to new analytical methods, it was possible to prove that after the so-called onset point, yield stress increases exponentially with the increase of both heat rate measured by isothermal calorimetry and specific surface. This paper also identifies the existence of a direct proportionality between the increase of heat rate and the increase of specific surface area during the acceleration period, most likely reflecting the nucleation and growth nature at this stage of the cement hydration. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power 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.)

Advanced core materials and components for nuclear reactors of a new generation are tested in the BOR-60 reactor. A novel irradiation rig (IR) with a fuel heater is used for high-temperature tests of material samples. The irradiation rig features a number of advantages over ampoule-type irradiation rigs commonly used nowadays. Computational and experimental studies on an IR with a fuel heater have been conducted in the BOR-60 reactor core. The results of a dedicated methodical experiment have proved that it is possible to provide the required temperature conditions for irradiation of tested samples. MCU-RR, a precision code, was used for neutronic calculations, and thermohydraulic calculations were performed using the ANSYS CFX software system. A comparison of calculated temperature values against experimental data has shown a fit in the experimental error limits which confirms the applicability of the selected codes, models and procedures. Computational and experimental studies have also been conducted for the temperature distribution in the IR with a fuel heater following the withdrawal of the IR from the reactor and its placement in a dry cooling channel. The decay power in the IR fuel pins were calculated using the AFPA code and the temperature fields were calculated based on ANSYS CFX. It has been shown that the permissible temperature value on the fuel cladding is not exceeded in the IR withdrawn from the reactor following two-day cooling after the reactor shutdown.