Thermal Energy Generation Research Articles

Mixed Thermal and Renewable Energy Generation Optimization in Non-Interconnected Regions via Boolean Mapping

Global efforts aiming to shift towards renewable energy and smart grid configurations require accurate unit commitment schedules to guarantee power balance and ensure feasible operation under different complex constraints. Intelligent systems utilizing hybrid and high-level techniques have arisen as promising solutions to provide optimum exploration–exploitation trade-offs at the expense of computational complexity. To ameliorate this requirement, which is extremely expensive in non-interconnected renewable systems, radically different approaches based on enhanced priority schemes and Boolean encoding/decoding have to take place. This compilation encompasses various mappings that convert multi-valued clausal forms into Boolean expressions with equivalent satisfiability. Avoiding any need to introduce prior parameter settings, the solution utilizes state-of-the-art advancements in the field of artificial intelligence models, namely Boolean mapping. It allows for the efficient identification of the optimal configuration of a non-convex system with binary and discontinuous dynamics in the fewest possible trials, providing impressive performance. In this way, Boolean mapping becomes capable of providing global optimum solutions to unit commitment utilizing fully tractable procedures without deteriorating the computational time. The results, considering a non-interconnected power system, show that the proposed model based on artificial intelligence presents advantageous performance in terms of generating cost and complexity. This is particularly important in isolated networks, where even a-not-so great deviation between production and consumption may reflect as a major disturbance in terms of frequency and voltage.

Bioinspired Spectrally Selective Phase‐Change Composites for Enhanced Solar Thermal Energy Storage

AbstractIntegrating solar thermal conversion with phase change materials (PCMs) offers a promising pathway for continuous thermal energy generation with a zero‐carbon footprint. However, substantial infrared radiation losses at elevated temperatures often hinder the efficiency of such integrated systems. Inspired by the thermoregulation mechanisms of polar bears, this work introduces composite PCMs with spectrally selective absorption to enhance solar thermal energy storage efficiency. These composite phase change materials (CPCMs), featuring densely packed SiC ceramic grains with high porosity, exhibit a thermal conductivity of up to 14 W m−1 K−1 and an energy storage density of 195.1 kJ kg−1. The incorporation of nanoparticle‐coated foil induces a plasmonic effect that increases solar absorptivity to 90.57% and reduces infrared emissivity from 71.94% to 7.47%. Consequently, the solar thermal storage efficiency is significantly increased from 54.56% to 81.65% at 500 K, effectively addressing the challenges associated with high‐temperature solar thermal storage. Additionally, the low infrared emissivity of the c (PNC), combined with the inherent heat absorption properties of PCMs, enables infrared stealth functionality. These multifunctional CPCMs demonstrate considerable potential for advancing high‐temperature solar thermal storage technologies and other heat‐related applications.

Enhancing Hybrid Photovoltaic-Thermal System Efficiency with Boron Dipyrromethene Dyes.

A library of boron dipyrromethene (BODIPY) compounds was studied to assess their efficacy as components of a working liquid in hybrid photovoltaic-thermal (PVT) systems. Two series of BODIPY dyes were investigated: series I included alkylBODIPYs with varying substitution patterns, while series II included 1,3,5,7-tetramethyl-substituted BODIPYs featuring electron-rich aromatic groups in the meso position, such as naphthalene, anthracene, and carbazole. Series II dyes were designed to exhibit luminescence downshifting due to enhanced UV absorption (300-400 nm) and excited-state energy transfer, leading to visible-region fluorescence under UV excitation. Samples of PVT liquids based on decalin and containing each individual BODIPY dye were tested on a standard a-Si solar cell to evaluate their impact on solar energy conversion efficiency. The thermal behavior of the working liquid and the cell during the illumination cycle was monitored, alongside the cell's electrical characteristics. Energy conversion pathways and the overall effects of the dyes on the system performance were scrutinized. Results indicated that all BODIPY dyes enhanced both the electrical conversion efficiency (up to 2.41% increase) and thermal energy generation (up to 6.87%) compared to the solvent alone. These findings highlight the potential of BODIPY dyes to significantly improve the performance of PVT systems.

Thermal radiation effect in electroosmosis regulated peristalsis transport of Williamson hybrid nanofluid via an asymmetric tapered channel

AbstractElectroosmosis effects in a peristaltic transport of nanofluids are significant for developing the biomimetic pumping structure at a microscopic extent in physiological medications, for instance, ocular drug delivery systems. The present article addresses the numerical assessment of a peristaltically driven electro‐osmotic flow of a Williamson hybrid nanofluid. The flow is intended to be two‐dimensional, incompressible, unsteady, and subjected to an asymmetric tapered micro‐channel. The characteristics of hybrid nanofluid, which consists of silver (Ag) and copper (Cu) as nanoparticles with base fluid‐blood, are explored in a relative manner with regular nanofluid Ag‐blood. Further, the study includes the impact of linear thermal radiation, energy dissipation through viscosity and resistance phenomena with an externally applied consistent magnetic field. The mathematical model is simplified using dimensionless similarity transformations and numerically solved via MATLAB software. Variations in momentum, thermal energy, and entropy generation against various emerging physical parameters are deliberated through graphical results. Longitudinal velocity towards the center line and heat transfer rate is also analyzed through numerical data illustrated in table form. This study introduces a novel mathematical model for the peristaltically driven electroosmosis flow of Ag‐Cu/blood hybrid nanofluid in a tapered asymmetric microchannel, incorporating external electric and magnetic field effects.

Comprehensive Performance Analysis of Hybrid Solar Water Heating Systems: Synergizing Photovoltaic and Thermal Technologies

Abstract: Solar water heaters are an efficient and sustainable technology for meeting the growing demand for hot water in residential and commercial applications. This abstract presents a comprehensive overview of the performance evaluation of solar water heater systems through an extensive experimental study. The study aims to assess the effectiveness and efficiency of different solar water heater configurations under varying operating conditions. The experimental investigation involved the measurement and analysis of key performance parameters such as solar collector efficiency, heat transfer efficiency, thermal storage capacity, and overall system efficiency. A range of factors including solar radiation intensity, ambient temperature, water flow rate, and collector tilt angle were systematically varied to examine their impact on system performance. The results of the experimental study demonstrated the significant potential of solar water heaters in providing cost-effective and environmentally friendly hot water solutions. The solar collector efficiency was found to be highly influenced by the solar radiation intensity, with higher levels of solar irradiation leading to increased thermal energy generation. The heat transfer efficiency was optimized by adjusting the water flow rate and collector tilt angle, ensuring efficient transfer of heat from the collector to the water. Furthermore, the thermal storage capacity of the system played a crucial role in maintaining a consistent supply of hot water during periods of low solar radiation or high demand. Overall system efficiency was found to be strongly dependent on the integration of efficient heat exchangers and insulation materials. Based on the experimental findings, recommendations for system design and optimization were formulated, highlighting the importance of proper sizing, selection of suitable materials, and appropriate control strategies. The results also identified areas for future research, such as the integration of advanced heat transfer enhancement techniques and the utilization of hybrid solar water heater systems

Potential use of methane gas from the Villavicencio sanitary landfill, Colombia

The study evaluates the generation and recovery capacity of methane at the Villavicencio Landfill in Colombia, using the LandGEM model. It shows a significant increase in methane generation, rising from about 1.5 million cubic meters in 2010 to over 8.5 million in 2020, indicating a growing urgency to implement effective mitigation measures. It was estimated that by the year 2042, the electrical energy production from methane could be 248.067 kW/day, capable of supplying about 43.705 homes monthly. Additionally, thermal energy generation would be 468.572 kWh/day, useful for industrial processes. Management scenarios were proposed, where, for example, operational optimization could increase electric production to 342.333 kW/day, benefiting more than 60.000 homes monthly. The conclusions highlight the direct correlation between the amount of waste and methane generation, and the significant potential for converting these emissions into energy, pointing towards regional energy self-sufficiency and sustainability. Methane recovery represents a valuable alternative to the dependence on fossil fuels and for the development of a circular economy.

A Rome district transition towards optimal and sustainable heat and power generation

In this work, a specific district of Rome energy metabolism has been studied to reduce the carbon footprint of electric and thermal energy generation. Two scenarios were investigated, one “ex-ante” with the district as it was, fully dependent on the national grid for electricity and methane-fuelled boilers for heating. And an “ex-post” scenario with the buildings retrofitted with more efficient thermal insulation, LED lights, photovoltaic panels and trigeneration systems. The energy metabolism of the district was modelled in TRNSYS in both cases. For the ex-post scenario, the digital twin implemented a control logic for energy flows with several functionalities including prioritizing the power flow, setting rules and boundaries on the operation of the co-generators, preventing batteries from overcharging/discharging. The sizing of PV panels, batteries, and cogeneration units in the ex-post scenario was optimized in terms of both energy and economic performance using a Python library with the Non-dominated Sorting Genetic algorithm (NSGA-II). In the ex-post scenario, the optimal energy system delivers significant reductions in energy costs and CO2 emissions. The energy transition results in a decrease in purchased electricity of 68.2%, CO2 emissions by 56% and generation costs by 48.9%. The Levelized Cost Of Energy (LCOE) of the district is estimated to be 196 €/MWh.

A Numerical Simulation of the Magneto-Micropolar Nanofluid Flow Configured by the Stimulus Energies and Chemical Interaction

Inspired by the numerous applications of non-Newtonian nanomaterials in science and industries, the two-dimensional convective hydromagnetic movement in a micropolar nanofluid within an expanding permeable surface with the existence of binary chemical reaction and convective boundary constraints is examined in this study. Thermal radiation, energy generation, and activation energy interactions are employed to handle the nanofluid flow. The underlying equations are transformed via the similarity transitions into an array of non-linear ODE. The BVP4C MATLAB package is applied to solve the system of equations numerically. The necessary outcomes of the micropolar fluid velocity, micro-rotation, temperature, concentration, friction factor, mass transfer, and heat transfer rates are shown graphically and thoroughly analyzed quantitatively. The micropolar nanofluid’s mobility is reduced by the heating and solutal Grashof numbers. It is noted that the magnetic coefficient decreases velocity, it has the opposite impact on the degree of temperature. The plotted outcomes also show that the temperature increases as the increase in stimulation radiation variable. Meanwhile, the thermal field exhibits strengthen as the intensity of Biot number and Eckert number responses enhances. The growth of the activation energy leads to a noticeable enrichment in the concentration profile.

Analytical investigation of heat and mass transfer in MHD nano fluid flow past a moving vertical plate

This study aims to derive analytical expressions for temperature, concentration, and velocity in an unsteady MHD convective nanofluid flow past a moving vertical plate. The governing nonlinear differential equations are solved analytically using the Homotopy Analysis Method (HAM). The resulting solutions are presented as concentration, temperature, and velocity profiles, allowing for the analysis of various physical parameters' influence on the flow behavior. Furthermore, our analytical results are validated by comparing them with existing numerical solutions using MATLAB. The impact of these parameters on skin friction, the Nusselt number, and the Sherwood number is presented, demonstrating good agreement with previously reported data. The findings of this research hold significance for industries involving heat transfer processes, such as thermal management systems, electronic cooling, and energy generation applications.

Sodium alginate-based MHD ternary nanofluid flow across a cone and wedge with exothermic/endothermic chemical reactions: A numerical study

The use of magnetohydrodynamic ternary nanofluid flow for heat transfer is essential in various industrial and commercial applications. This work examines heat transfer over cone and wedge shapes with Sodium Alginate-based ternary nanofluid flow, considering the effects of activation energy and exothermic/endothermic processes. Using similarity transformations, the controlling set of partial differential equations is converted into a network of interconnected nonlinear ordinary differential equations. Numerical solutions using the Runge-Kutta Fehlberg 4th 5th order method and shooting approach offer insights into the effects of several dimensionless factors. The outcomes show that the magnetic field parameter is crucial in lowering fluid velocity within a cone more efficiently than a wedge. Due to activation energy considerations, the cone shape notably impacts heat transmission in exothermic reactions, but the wedge geometry is more effective in endothermic reactions. Concentration profiles rise with activation energy and fall with increasing chemical reaction rates. The rate of thermal distribution is 48.68% more in wedge than cone geometry for the exothermic case and 35.57% in the endothermic case while the rate of mass transfer is higher in cone geometry than wedge geometry, about 7.83% in the exothermic case and 19.27% in the endothermic case. The present study has many applications, including optimizing heat transfer processes in sectors such as thermal systems, energy generation, and electronics. Additionally, it may be used to guide the design of magnetically affected systems and provide assistance for uses in chemical engineering.

Numerical Investigation of PV/T System by Using Graphene Based Nanofluids

The effective use of solar radiation can be maximized by the implementation of a novel hybrid device referred to as a photovoltaic thermal collector (PV/T), which has the capability to simultaneously generate both electrical and thermal energy. As temperature increases, the efficiency of the photovoltaic (PV) cell drops. The present work employs graphene nanofluids as a means to decrease the temperature of the system in order to evaluate the photovoltaic thermal (PV/T) performance. The PV/T system is subjected to Computational Fluid Dynamics (CFD) simulation, wherein graphene nanofluids of different volume concentrations (0%, 0.1%, 0.2%, and 0.3%) and mass flow rates (0.065, 0.075, and 0.085 kg/s) are employed. The PV/T system demonstrated enhanced performance as a result of the implementation of the proposed approach, which effectively reduced the temperature of the solar cell during the period of maximum solar radiation, spanning from 9 AM to 4 PM. The utilization of the system was employed for the generation of thermal and electrical energy due to its respective thermal and electrical efficiency of 67% and 11.5%. The completed research has demonstrated that the integration of graphene nanofluids has the potential to enhance the efficiency of PV/T systems.

Nonlinear thermoelastic wave propagation in general FGM sandwich rectangular plates

The present work is dedicated to investigating the thermoelastic wave propagation behavior of sandwich rectangular plates (SRP) made of functionally graded material (FGM). The main contribution lies in the partial modification of basic theoretical expressions and solution methods to improve the accuracy of practical system models. An analytical model with three types of general configurations is established. The porosity distribution in FGM layers depends on the degree of mixture of the constituent materials, with the FGM layers without porosity taken as a reference model. The effect of porosity within FGMs is addressed through a refined analytical formulation of material properties, and the temperature-dependent material properties of FGM sandwich structures (FGMSS) maintain continuity through the thickness. This improved framework introduces a porosity function encompassing three distinct structural and geometrical functions: the core-to-thickness ratio (CTR), porosity volume fraction (PVF), and porosity distribution function (PDF). It is worth mentioning that the theoretical expressions maintain good continuity and reliability under the influence of thermal conditions and system parameters of the proposed structures. Furthermore, considering the generation of thermal strain energy (TSE) caused by thermal expansion of the structure in the normal direction, an improved analytical approach for determining TSE in rectangular plate structures is then investigated by introducing the Green's nonlinear strain (GNS). Hamilton's principle is applied to derive the wave motion equations and analytical solutions for the wave dispersion relations are derived. Furthermore, accurate numerical simulation is performed and the solution is verified with data available in published resources. In addition, we present a systematic parametric analysis to examine the effects of porosity, configuration, power-law exponent (PLE), PVF, CTR, temperature, and wave number on the thermoelastic wave propagation behavior of FGMSRP.

Thermal Energy Storage Using Phase Change Materials in High-Temperature Industrial Applications: Multi-Criteria Selection of the Adequate Material.

Thermal energy storage (TES) plays an important role in industrial applications with intermittent generation of thermal energy. In particular, the implementation of latent heat thermal energy storage (LHTES) technology in industrial thermal processes has shown promising results, significantly reducing sensible heat losses. However, in order to implement this technology, a proper selection of materials is important. In this study, a new multi-criteria phase change material (PCM) selection methodology is presented, which considers relevant factors from an application and material handling point of view, such as hygroscopicity, metal compatibility (corrosion), level hazard, cost, and thermal and atmospheric stability. The methodology starts after setting up the system requirements where the PCM will be used, then a material screening is able to find all possible candidates that are listed with all available properties as listed before. Then, a color map is produced, with a qualitative assessment of material properties drawbacks, hazard level, melting enthalpy, and price. The experimentation starts with a preliminary set of tests on hygroscopicity and one-week corrosion test, which allows disregarding PCMs and selecting a short list of potential PCMs that would need further characterization before the final selection.

Further insights into steady three-dimensional MHD Sakiadis flows of radiating-reacting viscoelastic nanofluids via Wakif’s-Buongiorno and Maxwell’s models

AbstractKeeping in mind the stress relaxation tendency of many viscoelastic multi-phase flows (e.g., polymer solution flows and transport phenomena of red cell suspensions within blood media), the present research investigation intends principally to develop a realistic model for revealing properly the aspects of reacting-radiating Maxwell nanofluids during their laminar boundary layer flows in the steady regime over a horizontal impermeable surface under a transversal magnetic influence. For this purpose, the principal leading differential formulation is derived theoretically by linking Wakif’s-Buongiorno approach with Maxwell’s model. By invoking fundamentally the general boundary layer assumptions and the passive control strategy for the nanoparticles, the governing PDEs’ formulation is simplified accordingly and then stated properly for the case of the convective heating condition at the impermeable bi-stretching surface. By executing a feasible non-dimensionalization technique, the monitoring ODEs’ system is achieved successfully, whose solutions are presented precisely in different illustrative scenarios using Richardson’s extrapolation method. After carrying out successfully several validating tests, it is demonstrated that the weakly viscoelastic feature has generally a slight delaying effect on the nanofluid motion. This dynamical weakening can be reinforced more with the generation of thermal energy by intensifying the external magnetic field source. Additionally, these physical factors show an intensifying influence on the surface drag forces. However, a dropping impression is seen for the local heat transfer at the contact surface. Contrary to the broadening impact of the radiative heat transfer as well as the convective heating and thermophoresis mechanisms on the thermal and mass boundary layer regions, it is witnessed that the first-order chemical reaction mechanism and Brownian’s motion exhibit a shrinking impact on the mass boundary layer region.

Performance of the Heat Pump and Photovoltaic Systems Installed in the Single-family House

Renewable energy sources are increasingly common in Poland, and a growing number of single-family houses are now equipped with such systems. The article presents the study of the performance of the heat pump and the photovoltaic system installed in a house in the Swietokrzyskie Province near the city of Kielce. The data related to thermal and electrical energy generation throughout three years has been analysed with a focus on the advantages offered by such systems in the climate conditions of Central Poland. It turned out that 2022 was the best year for electricity production because it exceeded the value of 8000 kWh, and in the winter period from November to February, energy production balances at 200-300 kWh, which proves the high efficiency of panels for electricity production even in unfavourable climatic conditions. The heat pump generates the smallest energy production to heat the house in the summer, while in the winter, this production increases intensively due to the heating season in Poland. These are values from 1500 kWh to values above 3000 kWh. Similarly, in the case of domestic hot water, these values are higher in winter than in summer. Additionally, the work includes electricity consumption before and after the installation of renewable energy sources. Simplified economic analysis has also been presented in the paper. The simple payback period is estimated at approximately 9 years.

The Influence of Ozone on the Flame Propagation Behavior of n-Heptane/air and i-Octane/air Premixed Flame in an Engine-Relevant Environment

ABSTRACT The promotional effect of ozone on lean premixed spherical flame propagation in an engine-relevant, high-temperature, high-pressure environment was investigated using an optically accessible rapid compression and expansion machine (RCEM). The laminar burning velocity, burned gas Markstein length, and initial flame development time based on mass fraction burned (MFB), were examined for n-heptane/air and i-octane/air premixture (φ = 0.55) with 15 [ppm] ozone, through self-emission observation of a propagating flame with a high-speed camera and combustion pressure analysis. The results showed that ozone reduced the initial flame development time and increased the laminar burning velocity for n-heptane/air premixture under temperature conditions in which the low-temperature oxidation (LTO) reaction was more clearly pronounced; but ozone did not enhance either the initial flame development or the laminar burning velocity in the case of i-octane/air premixture, where the LTO reaction was weak owing to the fuel molecular structure, even under the same temperature conditions. These results suggest that the enhancement of the LTO reaction by ozone, and the subsequent generation of thermal energy and CO radicals through an H2O2 loop reaction in the pre-flame region, were responsible for the increase in the laminar burning velocity. Furthermore, ozone increased the burned gas Markstein length, flame thickness, and Zeldovich number of the n-heptane/air mixture under the temperature conditions in which the laminar burning velocity was enhanced by ozone. This suggests that the chemical reaction in the reaction zone was more active in response to the increase in flame temperature.

Optimal operation and control of hybrid power systems with stochastic renewables and FACTS devices: An intelligent multi-objective optimization approach

This paper delves into the increasingly complex domain of Optimal Power Flow (OPF) within modern power systems, enhanced by the integration of unpredictable renewable energy sources. The research originally integrates stochastic photovoltaic and wind energy sources, along with a suite of Flexible AC Transmission System (FACTS) components – including thyristor-controlled series compensators, static VAR compensators, and thyristor-controlled phase shifters. The primary objective is to solve the OPF problem by reducing generation costs while accommodating the variable nature of renewable energy sources and load demands. This study prioritizes the examination of both constant and fluctuating load requirements. The inherent variability of PV and wind energy, along with load demand, is captured through the modelling of probability density functions. This approach enables a more detailed optimization process, incorporating not just the cost of thermal energy generation but also the scheduling costs of renewable sources and associated penalty costs. Moreover, the study examines the strategic placement and sizing of FACTS components, an aspect essential in minimizing the overall cost of power production. Employing both single- and multi-objective optimization algorithms, the research addresses the OPF problem in a modified IEEE-30 bus system through various case studies. The application of the recently developed flow direction algorithm, including its multi-objective variant with an ε-based constraint-handling mechanism to OPF problem is the primary contributions of this work. The results, benchmarked against several advanced metaheuristic algorithms, reveal the proposed algorithm's superior performance. This comprehensive study not only underscores the potential of integrating renewable energy sources into the grid but also highlights the efficacy of intelligent optimization strategies in managing the complexities of modern power systems.

Activation energy analysis of mobile microorganisms using conductive nanofluid flows: Mitigating toxic algal blooms in biotechnology applications

Motile microorganisms play a central role in ecosystems in both natural habitats and laboratory settings. Their contribution to nutrient cycling is crucial and their impact on human health can be significant. Furthermore, they are promising in various biotechnological applications. Ongoing studies of microbial motility represent a dynamic and evolving field of research with profound implications for our understanding of biology, ecology, and environmental science. The thermal properties of the base material are extremely advanced and enable a wide range of industrial, technical and process applications due to their thermal radiation, variable heat transfer properties and activation energy. Researchers are still working hard to find renewable energy sources that are both economical and environmentally friendly. In this regard, the past decade has seen growing interest in the potential of nanoparticles as renewable energy sources. The current study aimed to learn more about the rheological properties of thixotropic nanofluids on the surface of Riga surrounded by rotating bacteria. For this, theoretical investigations have been performed on 3D magneto-hydrodynamic micropolar-based Casson nanofluid on the surface of Riga surrounded by rotating bacteria. The influence of thermal radiation, activation energy and heat generation are considered in the present scenario. The rheology of Brownian motion, micro rotation and thermophoresis also accounted for. Classical equations of motion in the form of PDEs are transformed into ODEs by applying similarity variables. The converted ODEs are then solved with the help of a shooting algorithm using Bvp4c MATLAB software. From an engineering point of view, the impression of physical flow parameters dimensionless profiles is demonstrated graphically and in the form of tables. The outcomes show that enhancing the porosity parameter significantly reduces the velocity profiles while the opposite behaviour is noted for the viscoelastic parameter. Moreover, temperature and concentration fields are boosted by thermophoresis and concentration exponents. Present results are validated with the existing ones. The current study has the potential to improve the stability achieved by the bioconvection of nanomaterials.

Повышение энергетической эффективности газопоршневой ТЭС за счет комплексного использования тепловых вторичных энергоресурсов

Recently, the advantages and prospects to use piston gas internal combustion engines for the combined generation of electrical and thermal energy have become increasingly obvious. The range of single capacities of gas piston units (GPU) ranges from 0,1 MW to tens of MW, which makes them more attractive when designing various power facilities. Most brands of gas piston units can operate in co-generation mode, that is, as a combined heat and power plant that simultaneously generates electrical and thermal energy. The purpose of this study is to substantiate the possibility of integrated use of heat of the cooling systems of the gas piston engine of a thermal power plant (TPP). The studies conducted are carried out using well-known methods of thermodynamic calculation of the internal combustion engine cycle, of determination of the components of its thermal balance and thermal calculation of the equipment for utilization of secondary thermal energy resources. The results of the analysis of the heat losses of the GPU drive engine have showed that the total losses during its operation are about 11544,5 kW. Average potential heat losses with flue gases are 45,87 %, and low-potential heat losses with water in cooling systems and oil in lubrication systems are 53,14 %. A schematic diagram is proposed for the integrated utilization of thermal renewable energy resources (RES) at a gas piston thermal power plant. The main difference between the proposed scheme and the existing technical solutions is the utilization of the heat of the low-temperature charge air cooling system after the second section of the compressor and the heat of the engine lubrication system. An analysis of the expenditure part of the energy balance of the drive engine in case of the integrated use of thermal RES in the GPU cycle, has showed that the implementation of energy-saving measures will make it possible to usefully use up to 93,05 % of the supplied energy in the generation of electrical and thermal power.

Microbial community dynamics and functional potentials in the conversion of oil palm wastes into biomethane.

Oil palm processing generates substantial waste materials rich in organic content, posing various environmental challenges. Anaerobic digestion (AD), particularly for palm oil mill effluent (POME), offers a sustainable solution, by converting waste into valuable biomethane for thermal energy or electricity generation. The synergistic activities of the AD microbiota directly affect the biomethane production, and the microbial community involved in biomethane production in POME anaerobic digestion has been reported. The composition of bacterial and archaeal communities varies under different substrate and physicochemical conditions. This review discusses the characteristics of POME, explores the microbial members engaged in each stage of AD, and elucidates the impacts of substrate and physicochemical conditions on the microbial community dynamics, with a specific focus on POME. Finally, the review outlines current research needs and provides future perspectives on optimizing the microbial communities for enhanced biomethane production from oil palm wastes.