Sustainable Energy Sources Research Articles

Bacterial cellulose materials in sustainable energy devices: A review.

This article provides a comprehensive review of the processing and applications of bacterial cellulose (BC) for energy conversion and storage devices. These emerging technologies enable the transformation of sustainable energy sources into electricity. Once converted, energy storage devices are vital for stable energy supply. To promote green manufacturing practices in this field, bio-based materials are explored as alternative materials for energy devices, addressing the growing demand for sustainable solutions. From a research and development perspective, the materials chosen for energy devices must exhibit exceptional mechanical, electrical, and thermal properties, along with the necessary chemical reactivity to unlock new applications. Furthermore, for successful commercialization and industrialization, these materials must be suitable for large-scale production within practical timeframes. BC fulfills all of these requirements. The review begins with an overview of BC growth, detailing the composition and operating parameters of the culture medium and the design of bioreactors for large-scale production. It then defines and summarizes both in-situ and ex-situ modifications and processing strategies, offering a comprehensive perspective on these techniques. Unique and interesting properties linking BC's structure to its properties are reviewed to demonstrate its potential as a substitute for benchmark materials. The exceptional performance and synergistic effects of BC-derived hybrid materials highlight their potential for state-of-the-art applications in energy devices, and are suitable for the next-generation energy devices. The papers reviewed in this work have gained significant attention and been widely cited over the past 10years for their relevance to various practical applications, allowing readers to have a better understanding in development of BC based materials for energy conversion and conversion devices.

Green carbon and the chemical industry of the future

The pressing need to mitigate climate change and drastically reduce environmental pollution and loss of biodiversity has precipitated a so-called energy transition aimed at the decarbonization of energy and defossilization of the chemical industry. The goal is a carbon-neutral (net-zero) society driven by sustainable energy and a circular bio-based economy relying on renewable biomass as the raw material. It will involve the use of green carbon, defined as carbon derived from terrestrial or aquatic biomass or organic waste, including carbon dioxide and methane emissions. It will also necessitate the accompanying use of green hydrogen that is generated by electrolysis of water using a sustainable source of energy, e.g. solar, wind or nuclear. Ninety per cent of the industrial chemicals produced in oil refineries are industrial monomers that constitute the precursors of a large variety of polymers, many of which are plastics. Primary examples of the latter are polyolefins such as polyethylene, polypropylene, polyvinyl chloride and polystyrene. Polyolefins are extremely difficult to recycle back to the olefin monomers and discarded polyolefin plastics generally end up as the plastic waste that is responsible for the degradation of our natural habitat. By contrast, waste biomass, such as the lignocellulose contained in forestry residues and agricultural waste, constitutes a renewable feedstock for the sustainable production of industrial monomers and the corresponding polymers. The latter could be the same polyolefins that are currently produced in oil refineries but a more attractive long-term alternative is to produce polyesters and polyamides that can be recycled back to the original monomers: a paradigm shift to a truly bio-based circular economy on the road to a net-zero chemical industry. This article is part of the discussion meeting issue ‘Green carbon for the chemical industry of the future’.

Harnessing geothermal energy in Hungary

This paper provides a summary of the current status of geothermal energy utilisation in Hungary, with a brief reference to geothermal potential. Approximately 1,000 thermal wells are in operation, producing from two principal aquifers: carbonate aquifers (predominantly Mesozoic) and Upper Miocene siliciclastic aquifers. The utilisation of geothermal energy in Hungary commenced with balneological exploitation, with documented evidence dating back to the Roman era. Of particular note is the city of Budapest, which has the distinction of being home to 16 thermal spas, a fact that has led to its designation as the spa capital of Europe. In the Hungarian portion of the Pannonian Superbasin, 26 municipalities have implemented geothermal district heating systems. Furthermore, geothermal energy plays a significant role in the agricultural sector, with approximately 300 thermal wells currently in operation. Nevertheless, the generation of geothermal electricity is still in its infancy, with only one operational geothermal power plant. However, based on the exploration permits submitted, there are significant prospects for further development. The same is true for ground source heat pumps, where there is considerable potential for growth, particularly in comparison to our neighbouring country's utilisation. Recent research directions are promising, ranging from the use of geothermal energy from abandoned hydrocarbon wells as deep borehole heat exchangers, to the potential for extracting critical materials from thermal water, to exploring the possibility of underground heat storage. The favourable geothermal conditions in Hungary offer the potential to achieve up to 15-20 times the current production of 6.5 PJ, assuming the application of existing technologies. This presents a significant opportunity for the transition to a more sustainable energy source, particularly in the context of heating.

Nanosized hyperbranched cobalt and metal-free phthalocyanine intercalated with Pd–C matrix using PVA-TEOS as binder for admirable supercapacitor properties

The expanding global economy resulted mainly from consuming fossil fuels, which are scarce and cause prodigious environmental harm. Mankind is shifting towards sustainable, efficient and clean energy sources known as green energy. The storage of green energy is an urge of time, to fulfil the energy requirements. Supercapacitors are gaining popularity in the field of energy storage due to their excellent safety, cost-effectiveness, and environmental friendliness. The forthright strategy of using a nitrogen-rich phthalocyanine macrocycle as a nanosized particle is to increase surface area resulting in a high specific capacitance. Herein, an innovative approach has been made by synthesising nanosized hyperbranched metal-free/Co-Phthalocyanine characterized by various analytical and spectroscopic techniques. The morphology of the composite was confirmed through physicochemical characterization like BET, SEM, XRD and electrochemical features were studied through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The electrode modification was carried out using the binder Poly (vinyl alcohol)-Tetraethyl orthosilicate (PVA-TEOS) crosslinked hybrid solution. The intercalated nanosized palladium on carbon matrix with HBCoPc and HBPc at different ratios enhanced the performance of capacitance. Amongst all the ratios, HBCoPc: Pd–C with 30:70 ratio has demonstrated superior specific capacitance of 824.25 F g−1 at 0.5 A g−1. Additionally, the fabricated electrode of HBCoPc: Pd–C and HBPc: Pd–C has exhibited good capacitance retention of 84.03 % and 81.01 % over 5000 cycles, respectively. This work delivers a promising approach towards the development of high-performance supercapacitors using metal phthalocyanine/metal-carbon composites as a new way to manufacture devices for conversion and energy storage.

Fabrication of high-performance of cost effective AgNbO3/rGO nanohybrid via hydrothermal route for supercapacitor applications

The supercapacitor has garnered attention from researchers in recent years which can be related to the rising need for sustainable energy sources. In this study, hydrothermal method is used to synthesize an AgNbO3/rGO nanohybrid for supercapacitor devices. The electrochemical outcomes revealed that AgNbO3/rGO nanohybrid high specific capacitance was measured as 1485 F g−1 at 1 A g−1. Furthermore, the obtained result indicates that the small charge transfer resistance (Rct = 0.71 Ω) across AgNbO3 and rGO was associated with high ion diffusion efficiency and even after the 5000th charging–discharging cycle and electrode has shown greater stability. This exceptional stability highlights the produced materials’ minimal Rct and outstanding life cycle stability. According to the study’s findings, the AgNbO3/rGO nanohybrid electrode has much promise as an electrode in various energy-storing applications.

Enhancing prediction of elemental composition through machine learning decision tree models for biomass gasification optimization

Abstract The worldwide transition to cleaner, sustainable energy sources, prompted by population growth and industrialization, responds to uncertain fossil fuel prices and environmental concerns, highlighting the substantial benefits of renewable energy in reducing greenhouse gas emissions and addressing climate change. Derived from non-fossilized organic materials, biomass emerges as a significant and sustainable contributor to renewable energy. Its diverse nature is complemented by a range of conversion technologies, encompassing combustion, pyrolysis, gasification, and liquefaction, providing versatile avenues for biomass energy transformation. Gasification, the transformative process of converting organic matter into combustible gases under controlled oxygen levels, is accomplished through direct oxygen supply or pyrolysis. This method yields a dependable gaseous fuel versatile for heating, industrial processes, power generation, and liquid fuel production. Machine learning employs advanced statistical techniques for modeling across diverse industries, showcasing particular efficacy in optimizing thermochemical processes by precisely identifying the optimal operating conditions required for achieving desired product properties. These models utilize proximate biomass data to predict the elemental compositions of N2 and H2. Assessment of both single and two hybrid models indicated that the introduced optimizers significantly enhanced the estimation of N2 and H2 when combined with Decision Tree (DT), with Decision Tree Coupled with Artificial Hummingbird Algorithm (DTAH) proving particularly effective. Notably, DTAH demonstrated outstanding performance with remarkable R 2 values of 0.990 for N2 and 0.992 for H2. Additionally, the minimal Root Mean Square Error (RMSE) values of 1.291 and 1.550 for N2 and H2 predictions respectively underscore the precision of DTAH, establishing it as a suitable choice for practical real-world applications.

Numerical investigation of heat and moisture migration in clayey and sandy soils, exploring seasonal fluctuations

Geothermal energy is widely known as a sustainable and eco-friendly energy source. For its applications, assessing the hydrothermal soil behaviour is crucial. However, the installation of ground geothermal systems at shallow depths makes them sensitive to atmospheric conditions, which affect the temperature field and the thermal balance. This paper presents the results of a numerical study investigating the hydrothermal behaviour of unsaturated soils (clay and sand), considering the meteorological variations at the ground surface. The atmospheric-soil interactions, including solar radiation, sensible heat flux, and latent heat flux, are essential for quantifying the energy balance and the hydro-thermal transfer processes taking place at the ground surface. By analysing these components, we can gain a comprehensive understanding of how energy is distributed and transferred to the soil. A numerical study was carried out using a finite element method (FEM) to assess the hydrothermal behaviour of unsaturated soils. The analysis of the obtained results from the model simulation reveals that variations in soil types have an impact on the distribution of heat and moisture migration, with both time and depth. Moreover, it appears that clayey soils show the highest efficiency in geothermal energy transfer. This research offers crucial insights into the optimization of both the design and implementation of geothermal systems.

Experimental study on the effects of n-butanol and n-propanol on the spray and combustion characteristics of diesel/biodiesel blends in a constant volume combustion chamber

The depletion of fossil fuel resources and the escalating environmental impact of greenhouse gas emissions have intensified the global exploration of renewable and sustainable energy sources. Biodiesel produced from vegetable oils and animal fats has become a promising alternative to conventional diesel fuel due to its renewability and lower carbon emission. This study investigates the differences in spray, combustion and flame characteristics between soybean-based biodiesel blended with propanol and butanol at various ratios. The results indicate that the liquid spray penetration length of biodiesel mixed with propanol and butanol exceeds that of soybean-based biodiesel. And the increase of spray penetration is accompanied by a longer flame lift-off length, which indicates the improvement of spray characteristics. Regarding combustion, alcohol-fuel blends exhibit a reduction in peak combustion pressure but an increase in peak apparent heat release rate. Additionally, these fuels show a shorter ignition delay and combustion duration. The peak natural flame luminosity is lower for alcohol fuels, suggesting their potential to reduce carbon soot production and support low-carbon combustion. These experimental results contribute to advancing research on cleaner, more efficient and renewable fuels, thereby reducing reliance on conventional fossil fuels.

Organoenergetic Investigation on the Potential of Industrial Brewers' Spent Grain Valorization for Biogas Production

Cameroon is a high country producer and consumer of beer in Africa which has various breweries generating a large amount of brewer spent grain (BSG) yearly. This study was designed to investigate the potential use of spent grains derived from the Cameroonian brewing industry as a viable and sustainable energy source for biogas production. A comprehensive proximate analysis was performed, focusing on key physicochemical parameters including moisture content, acidity level, ash content, and the proportions of proteins, carbohydrates, and fats, thereby enabling the derivation of their energy value to determine the organoenergetic profile. Physicochemical characterization of the spent grains revealed a pH of 5.6, moisture content of 8%, and ash content of 9.8% at 450 °C for 2 h using a muffle furnace. The organic composition included a high iron content of 194.2 mg/100 g, an organic matter content of 99%, a total organic carbon (TOC) content of 57.39%, a total nitrogen content of 3%, and a nitrogen-carbon ratio of 19.13%. In addition, the spent grains exhibited substantial concentrations of total protein (18.75%), crude fiber (3.6%), lipids (8.7%), and carbohydrates (51.15%), with an energy value of 14.97 MJ/kg. Moreover, the chemical oxygen demand (COD) was determined to be 3,880 mg/kg, while the lower calorific value (LCV) was 19.76 MJ/kg, resulting in a COD/TOC ratio of 86.03. These findings showed that the spent grain from Cameroonian brewery has a significant organ energetic potential based on its components and physicochemical properties, thereby highlighting their suitability as a valuable resource for biogas generation.

Dual carbon confining SnO2 nanocrystals as high-performance anode for sodium-ion batteries

The increasing global demand for sustainable energy sources has driven research into sodium-ion batteries (SIBs) for large-scale energy storage. However, their electrochemical performance is hindered by poor reaction kinetics and significant volume expansion in electrode materials. In this work, we developed a dual-carbon-confined SnO2 nanocrystal anode (CNTs@SnO2@NC) designed for high-performance SIBs. This innovative structure uses carbon nanotubes (CNTs) and a nitrogen-doped carbon (NC) coating to stabilize SnO2, ensuring structural integrity during charge/discharge cycles. The CNTs network in CNTs@SnO2@NC can alleviate the agglomeration of SnO2 nanocrystals to a certain extent; With its superior electronic conductivity, CNTs can enhance the anode's conductivity and function as an electronic highway; The sodiophilic properties and good electrical conductivity of CNTs enable sodium ions to migrate rapidly on the surface of the nanotubes. Moreover, numerous external defects and active sites generated by nitrogen doping enhance the sodium ion absorption capabilities; The existence of nitrogen-doped carbon coating can effectively accommodate the volume changes of SnO2 and enhance the structural stability of CNTs@SnO2@NC composites during the repeated charge and discharge cycles. As a result, the CNTs@SnO2@NC composite demonstrates excellent electrochemical performance, achieving capacity of 235 mAh g−1 at 0.1 A g−1 over 100 cycles and 102 mAh g−1 at 1.0 A g−1 over 300 cycles. In a full-cell configuration with a Na3V2(PO4)3 cathode, it delivers 38 mAh g−1 at 100th cycle at 0.1 A g−1. This study underscores the substantial improvements achieved by dual-carbon confinement for high-performance SIB anodes, offering a promising direction for future anode material design.

An Experimental Study Analysis of The Suitability of Sensible Heat Storage Materials for Solar Cooking Under Algerian Sahara Conditions

Solar power stands as a crucially sustainable energy source, primarily harnessed for heating and generating power. Various energy storage materials exist, enabling the improvement of diverse solar heating systems' performance. In this study, we've experimentally examined the thermal storage capabilities of small masonry brick pieces within a box-type solar cooker. This material was utilized atop the cooking plate in the tested cooker. The authors focused on making box cookers more efficient without breaking the bank, particularly benefiting those in remote areas. They explored using cost-effective heat storage materials, making it accessible even to those with limited education. Cooking trials showed promising results, indicating the practicality of affordable energy storage materials. These findings hint at the possibility of widespread adoption of the tested model. The cooker boasts a thermal efficiency of approximately 36.8%, a cooking power of around 61.10 W, and a thermal storage capacity of roughly 7 hours per day. The estimated cost for the cooker tested comes in at about $75.

Stretchable and Elastic Triboelectric Nanogenerator with Liquid-Metal Grid-Patterned Single Electrode for Wearable Energy-Harvesting Devices.

Triboelectric nanogenerators (TENGs) have garnered significant attention as efficient energy-harvesting systems for sustainable energy sources in the field of self-powered wearable devices. Various conductive materials are used to build wearable devices, among which, gallium-based liquid metal (LM) is a preferred electrode owing to its fluidity and metallic conductivity even when strained. In this study, a stretchable, elastic, and wearable triboelectric nanogenerator is designed using a single electrode fabricated by embedding LM grid patterns into a stretchable silicone substrate through a two-step spray-coating process. Contrary to conventional double-electrode TENG that is challenging to integrate to human body, the LM grid-patterned single-electrode TENG (LMG-SETENG) has a simplified design and provides more flexibility. The LMG-SETENG can generate voltages of up to 100V via triboelectrification upon contact with the human body, even under various degrees of strain, owing to the fluidity of the LM electrode. The generated energy can be utilized as a sustainable energy source to power various small appliances. Moreover, the proposed LMG-SETENG can be utilized in soft robotics, electronic skin, and healthcare devices.

Evaluating the Viability and Optimization of Plasma Pilot Plants

Nuclear fusion stands as a promising avenue for achieving a sustainable and abundant energy source. Central to this endeavor is the development of effective pilot plants capable of demonstrating the feasibility of fusion power on a commercial scale. This paper provides a comprehensive evaluation of three leading magnetic confinement fusion configurations: the Advanced Tokamak (AT), Spherical Tokamak (ST), and Compact Stellarator (CS).The Tokamak, characterized by its toroidal shape and strong magnetic fields, has been the most researched and developed fusion device. The analysis focuses on the challenges related to maintaining stability and minimizing disruptions. Furthermore, the optimization strategies involving advanced materials, superconducting magnets, and innovative plasma control techniques are discussed to enhance the Tokamak's viability. In contrast, the Spherical Tokamak, a variant with a more compact and spherical design, promises improved current advancements including the handling of higher heat loads and magnetic field configurations. The Stellarator, with its complex, twisted magnetic field structure, eliminates the need for continuous external current drive, addressing some intrinsic issues of the Tokamak. By comparing these configurations, the paper identifies the relative strengths and weaknesses of each approach in terms of confinement efficiency, operational stability, and engineering feasibility. The evaluation is supported by recent experimental data, simulation results, and technological advancements. Finally, the paper proposes a roadmap for the future development of fusion pilot plants, highlighting the need for an integrated approach that leverages the strengths of each configuration while addressing their individual challenges. The synthesis of this evaluation underscores the importance of continued research, cross-collaboration, and investment in advanced technologies to realize the goal of practical and economically viable fusion energy. This comparative analysis aims to provide a strategic framework for policymakers, researchers, and engineers in the fusion community, fostering informed decisions and prioritizing research efforts towards the most promising fusion energy configurations.

Geothermal distribution and evolution of fault-controlled Linyi geothermal system: Constrained from hydrogeochemical composition and numerical simulation

This study explores the Linyi geothermal field, located in Shandong Province, China, characterized by its non-magmatic, active fault-controlled geothermal system. Utilizing a combination of geochemical analyses, temperature measurements, and numerical simulations, a detailed genetic model of the geothermal system has been developed. The analysis included extensive water geochemical and isotopic characterization to determine reservoir temperature, depth, and origin of the geothermal waters. The thermal-hydro coupling model was integrated with these data to refine the thermal distribution and assess the evolutionary dynamics of the geothermal system. Our findings indicate that the geothermal anomalies in the Linyi field are predominantly controlled by hydrothermal convection within the Ordovician and Cambrian carbonate layers, facilitated by the high permeability of the Yishu Fault. The fault acts as a crucial conduit for meteoric water recharge, which undergoes significant heating due to the geothermal gradient in deeper rock formations. Isotopic analyses of hydrogen and oxygen revealed the meteoric origin of the geothermal waters, with recharge likely originating from the nearby Yimeng Mountains. Furthermore, the study established a conceptual evolutionary model to understand the mechanisms driving the geothermal resource development in the area. It was determined that the geothermal resources are typically fault-controlled, with significant potential for further exploration due to the identified hydrothermal anomalies at the fault's footwall. The model predicts the preservation of heated meteoric water in the reservoir rock for periods ranging from 10 to 50 thousand years, providing a sustainable source of geothermal energy. This comprehensive approach not only enhances the understanding of the heat accumulation mechanism but also highlights the potential for optimizing geothermal exploration strategies within fault-controlled geothermal systems.

Cost-benefit analysis of implementing a solar powered water pumping system – A case study

Solar-powered water driving scheme (SPWDS) has been successfully employed as a practical solution to guarantee reliable water supply in various hilly regions without electrical infrastructure. The Water Supply Systems / Schemes (WSS) focus on using pumping systems for delivering potable water to the community but face practical difficulties and financial hurdles at different implementation stages. These challenges encompass the practical complexities, the absence of non-renewable energy sources, and ongoing expenses for consumable and non-consumable items incurred during the water project's execution and maintenance. The present research study evaluates the performance of four water supply systems in Nepal which use solar energy as their primary power source. The key performance indicators are assessed, including the functionality index for facility distribution. Additionally, the research aims to evaluate the feasibility of transitioning from non-renewable to sustainable renewable energy source to achieve net zero energy consumption. This evaluation concentrates explicitly on calculating the cost-effectiveness index as a key metric. A proportional analysis is undertaken to evaluate the cost-benefit of the SPWDS, considering both the potential advantages and challenges associated with these initiatives. The present study affirms the technical feasibility and economic viability of operating a WSS using renewable and eco-friendly solar energy as the power source. This finding opens avenues for reducing energy consumption and contributes significantly to developing a policy framework to for tapping solar energy.

Wave energy assessment and wave converter applicability at the Pacific coast of Central America

Nowadays, numerous governments have instituted diverse regulatory frameworks aimed at fostering the assimilation of sustainable energy sources characterized by reduced environmental footprints. Solar, wind, geothermal, and ocean energies were subject to extensive scrutiny, owing to their ecological merits. However, these sources exhibit pronounced temporal fluctuations. Notably, ocean dynamics offer vast energy reservoirs, with oceanic waves containing significant amounts of energy. In the Central American Pacific context, the exploration of wave energy resources is currently underway. Accurate numerical wave models are required for applied studies such as those focused on the estimation of exploitable wave power; and even more so in Central American region of the Pacific Ocean where existing numerical models simulations have so far relied on coarse resolution and limited validation field data. This work presents a high-resolution unstructured wave hindcast over the Central American Pacific region, implemented using the third-generation spectral wave model WAVEWATCH III over the period between 1979 and 2021. The results of the significant wave height have been bias-corrected on the basis of satellite information spanning 2005 to 2015, and further validation was performed using wave buoy and acoustic Doppler current profiler (ADCP) records located in the nearshore region of the Central America Pacific coast. After correction and validation of the wave hindcast, we employed the dataset for the evaluation and assessment of wave energy and its possible exploitation using different wave energy converters (WECs). This evaluation addressed the need to diverse the energy portfolio within the exclusive economic zones of Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Colombia, and Ecuador in a sustainable manner. Moreover, a comprehensive analysis was carried out on the advantages of harnessing wave energy, juxtaposed with the imperative of regulatory frameworks and the current dearth of economic and environmental guidelines requisite for development within the region.

Trapping Ions to Enhance High-Field Energy Harvesting Performance by Filling Polar Macromolecular Dielectrics.

In the quest for sustainable and renewable energy sources, researchers and engineers have explored innovative technologies to harvest energy from various environmental sources. Dielectric elastomer generators (DEGs) with high energy harvesting performance have been proven to be promising energy collectors, but achieving a high dielectric constant (ε') and low electrical conductivity (EC) under high electric fields of dielectric elastomer (DE) simultaneously is a struggle, which poses significant challenges. In this study, high-content carboxyl group-grafted liquid polybutadiene (HCPB) is synthesized and then adopted as an organic dielectric filler to blend and cocross-link with a butadiene rubber (BR) matrix to prepare DE composites with high energy harvesting performance. The introduction of carboxyl groups enhances polarization while trapping free Al3+ in the matrix, which revolutionarily achieves a significant increase in ε' under extremely low EC. Ultimately, the contradiction between increased ε' and decreased EC under high electric fields is reconciled, resulting in a 30 HCPB/BR composite with high energy density (w = 91.9 mJ/cm3) and fine power conversion efficiency (PCE = 24.1%). This advancement paves the way for the development of HCPB/BR composite-based DEGs with enhanced ε' and energy harvesting performance.

Performance analysis of PID and SMC for PEMFC-based grid integrated system using nine switch converter - A comparative study

Hydrogen fuel cells are gaining popularity as a reliable and efficient sustainable energy source. They have found uses in electric vehicles and microgrid applications. A grid-connected microgrid system with a 60 kW proton exchange membrane fuel cell (PEMFC) is proposed. A PEM fuel cell-based generating unit is studied, using a sliding mode controller (SMC) in the control scheme and a nine-switch converter (NSC) for the system integration. The NSC is used to integrate the FC system with the utility grid and controls the system's power flow. This study is focused on the performance evaluation of the proportional-integral-derivative (PID) and SMC controllers. The controllers' gains are tuned using an improved arithmetic optimization method (IAOA). The article also emphasizes improving system performance and stability by incorporating SMC in the control scheme. The suggested system is exposed to different source and load-side disturbances for performance evaluation. Matlab/Simulink is used to model the proposed system and validated by the real-time OPAL-RT 4510.

Comprehensive energy, exergy, and environmental evaluation of integrated heat pipe photovoltaic/thermal systems using multi-objective optimization

The depletion of fossil fuels and their environmental emissions have led to a tendency toward the implementation of sustainable energy sources. This study aims to evaluate the energy, exergy, and environmental performance of photovoltaic/thermal systems-based heat pipes. Furthermore, the electrical exergy and thermal efficiency of the photovoltaic/thermal system are analyzed. In this regard, two methods of multi-objective evolutionary algorithm based on non-dominated sorting genetic algorithm II (NSGA II) and multi-objective particle swarm optimization (MOPSO) are utilized. The simulated heat pipes are regarded as thermosyphon and pulsating type with water and acetone as the working fluid. The novelty of this study lies in the comparative analysis of thermosyphon and pulsating heat pipes with water and acetone as working fluids in PV/T systems, combined with the application of advanced multi-objective optimization algorithms, offering a comprehensive. The result demonstrates that acetone, as a working fluid, can help achieve better performance compared towater, and also pulsating heat pipe illustrates greater performance rather than the thermosyphon heat pipe. Moreover, the result reveals that the electrical exergy efficiency of the photovoltaic panel equipped with thermosyphon heat pipe with acetone has increased by 14.2 % compared to the photovoltaic panels without the heat pipe. In addition, utilizing thermosyphon base photovoltaic/thermal system with acetone reduces the production of greenhouse gases by 894.5 CO2eqkg/m2.year, which is a further reduction of 156.8 CO2eqkg/m2.year compared to the photovoltaic panel without a heat pipe.

Prioritizing industrial wastes and technologies for bioenergy production: Case study

Energy supply stability in the industrial sector is crucial to maintain operational efficiency and avoiding costly disruptions. In the face of pressing environmental challenges, transitioning to sustainable, efficient, and eco-friendly energy sources is imperative. This study aims to assess the potential of industrial waste for bioenergy production in Khorasan Province, Iran, addressing the research gap of developing a comprehensive framework of criteria that was lacking in previous studies. Employing a combined technology and material assessment methodology, the research began with the collection and analysis of questionnaires to identify and weight critical criteria using Shannon Entropy and expert insights. The Additive Ratio Assessment method was then used to rank various types of industrial waste and technologies according to established value criteria. The Findings reveal that anaerobic digestion of organic waste emerges as the most viable bioenergy solution with an 85 % desirability score, followed by anaerobic digestion of sewage sludge and gasification of plastic waste, scoring 77.31 % and 69.41 %, respectively. The innovative aspect of this study is the development and implementation of five novel evaluation criteria, including process temperature, technology lifetime, production cost, waste collection cost, and waste separation cost, which have not been previously applied to the assessment of industrial waste for renewable energy production, especially in developing countries.