Search

Advanced knowledge of PV soiling can aid in the economic profitability of PV plants and efficient generation. This study introduces a novel approach for evaluating energy losses from soiling deposition on PV modules. Experimental investigations conducted under real outdoor conditions in Jaipur (India) were used to validate the model's accuracy, demonstrating close agreement (with MAPE < 3.6%). Annual soiling trends were also investigated for seven cities reflecting diverse climatic zones (hot-dry, warm-humid, composite, temperate, and cold) and pollutant (PM10) concentrations. The proposed model was also tested with three different cleaning thresholds using rainfall intensities of 1, 3, and 5 mm/day and energy yield reductions due to soiling were simulated. Consequently, the findings of this study underscore the significance of seasonal variations in soiling profiles for different cities and, thus, highlight the need to develop location-specific cleaning strategies for PV systems that also account for the soiling removal due to rain events. The significant contribution of this research is a simplistic modeling approach that addresses the relationship of PV soiling with the input parameters such as wind speed (WS), relative humidity (RH), rainfall, particulate matter (PM10), and tilt angle. Hence, the proposed method can calculate soiling losses worldwide irrespective of geographical differences. [ABSTRACT FROM AUTHOR]

The optimization of hydrothermal carbonization for sewage sludge (SS) was conducted in this study. The impact of three independent variables, namely biomass:water ratio (B/W) (10–30%), retention time (15–45 min), and temperature (150–250 °C), on hydrochar (HC) yield, higher heating value (HHV), and energy yield of SS was explored. Characterizations of SS and HCs were obtained by ultimate and proximate analysis, FTIR, SEM, and bomb calorimetry. Using Box-Behnken Design as a standard response surface methodology technique, a quadratic model was suggested to correlate the independent parameters for the effect of parameters on HC yield, HHV, and energy yield and also was used for finding the maximal thesis effective parameters at the optimal process condition. In the research, B/W, retention time, and temperature, respectively, were determined to be optimum for HC energy yield at 8.9 wt.%, 33.4 min, and 205.7 °C. The highest possible energy output was 82.5%. [ABSTRACT FROM AUTHOR]

This study investigates the impact of degradation in perovskite‐silicon tandem solar cells by means of energy yield (EY) modelling over the entire lifetime. First, we assess the impact on EY of degradation in the individual solar cell parameters of the perovskite top cell. Our analysis reveals that degradation in fill factor, due to a decline in perovskite top cell shunt resistance (RSh), has the most severe impact on the EY, emphasizing the imperative to rectify perovskite imperfections in thin film processing causing RSh decline. Second, we investigate implications of degradation in the perovskite top cell on the EY of current mismatched tandem solar cells. Third, we examine critical thresholds for the "acceptable degradation levels" in the perovskite top cell with regard to degradation in each solar cell parameter, assuming that the total loss in EY must be comparable to the degradation in state‐of‐the‐art silicon. Overall, our study highlights that degradation of the perovskite top cell needs to be assessed with care when extrapolating the impact on the lifetime EY of perovskite‐silicon tandem solar cells. The severity of degradation for different degradation mechanisms in a single junction perovskite solar cell cannot be translated one‐to‐one to tandem devices. [ABSTRACT FROM AUTHOR]

Seed cakes, by-products from the cold press extraction of vegetable oils, are valuable animal feed supplements due to their high content of proteins, carbohydrates, and minerals. However, the presence of anti-nutrients, as well as the rancidification and development of aflatoxins, can impede their intended use, requiring alternative treatment and valorisation methods. Thermal treatment as a procedure for the conversion of seed cakes from walnuts, hemp, pumpkin, flax, and sunflower into valuable products or energy has been investigated in this paper. Thermogravimetry shows the particular behaviour of seed cakes, with several degradation stages at around 230–280 and 340–390 °C, before and after the typical degradation of cellulose. These are related to the volatilisation of fatty acids, which are either free or bonded as triglycerides, and with the thermal degradation of proteins. Torrefaction at 250 °C produced ~75–82 wt% solids, with high calorific values of 24–26 kJ/g and an energy yield above 90%. The liquid products have a complex composition, with most parts of the compounds partitioning between the aqueous phase (strongly dominant) and the oily one (present in traces). The structural components of seed cakes (hemicelluloses, cellulose, and lignin) produce acetic acid, hydroxy ketones, furans, and phenols. In addition to these, most compounds are nitrogen-containing aromatic compounds from the degradation of protein components, which are highly present in seed cakes. [ABSTRACT FROM AUTHOR]

Mediterranean European cities are characterized by high population density and limited space for large-scale implementation of renewable energy installations. This paper addresses the optimization of renewable energy installations in Mediterranean dwellings with the scope of increasing their energy contribution and cost-effectiveness. In a case study for Malta, the three technologies studied were solar photovoltaics, solar water heating, and heat pump water heating. Technical and economic analyses were performed on a number of reference configurations using Polysun software (version 2022.8). Sensitivity analyses were also conducted to study the impact that different technical and economic factors have on the performance of the configurations considered. Finally, comparisons were made between the techno-economic results obtained from the reference and sensitivity analyses. Based on data collected, the presence of renewable energy source (RES) technologies in the residential sector of Malta was characterized and correlated with the types of dwellings considered. Among the results obtained, it was found that although a solar RES installation may experience some shading, this does not mean that it is rendered economically unfeasible. Moreover, from the simulations conducted, electrical energy storage technology was considered as too premature unless strongly subsidized, making economic sense only in specific circumstances. On the other hand, although heat pump water heating technology is also relatively modern, it was concluded to be the most beneficial in terms of both energy yield and economic benefit, generally speaking. Furthermore, it was determined that in a higher occupancy dwelling, solar water heating (SWH) and heat pump water heating (HPWH) result in considerably more attractive energy savings. [ABSTRACT FROM AUTHOR]

We provide a comprehensive analysis of the effect of spectral albedo on photovoltaic (PV) module measurements and system model predictions. We demonstrate how to account for albedo in indoor bifacial device measurements by adjusting the applied irradiance using the scaled rear irradiance method, exemplified on fabricated silicon heterojunction (SHJ) modules. System model performance is studied using a detailed 3D finite‐element model, DUET, for fixed‐tilt and horizontal single‐axis tracked (SAT) arrays between 15 and 75°N. Spectral effects cause variations in measured SHJ module short‐circuit current up to 2% and efficiency variation up to 0.3% abs. We further demonstrate that rear‐side spectral mismatch factors (SMMs) resulting from including or omitting spectral albedo in PV system modeling vary between ±13%, while total (front+rear) SMMs vary up to 3%, depending on the deployment configuration and latitude. SAT array SMMs are weakly correlated with latitude, while fixed‐tilt array SMMs increase with latitude, driven by an increasing proportion of ground‐reflected light on the front‐side of modules. Ground‐reflections can constitute between 2% and 32% of total incident module irradiance, with notably high (>10%) contributions for fixed‐tilt arrays at high latitude. Effects of spectral albedo are most significant for: (1) fixed‐tilt deployments at high latitudes, (2) wide bandgap technologies such as perovskite and cadmium telluride cells, (3) albedos which vary steeply over the technology's absorption range, and (4) high albedo ground covers. Overall, we demonstrate that omitting spectral albedo effects can result in PV measurement and system‐level modeling uncertainties on the order of several percent in these cases. [ABSTRACT FROM AUTHOR]

This work extensively develops and evaluates an XGBoost model for predictive analysis of gas turbine performance. The goal is to construct a robust prediction model by utilizing previous operational data, such as environmental variables and operational parameters. This study examines building a predictive model using the XGBoost algorithm, an ensemble learning approach known for handling huge datasets and producing robust predictions. The model is built to anticipate the gas turbine's Energy Yield (EY) output, optimize energy production efficiency, improve maintenance schedules, and enable operational decision-making within the power plant. The performance of the XGBoost model is carefully evaluated using effective evaluation metrics like RMSE, MSE, MAE, and R2 and validation methodologies, providing insights into its accuracy, robustness, and generalizability. The enhanced XGBoost predictive model's most notable feature is its ability to smoothly expand its forecasting skills to anticipate EY by applying the data acquired by anticipating positive and negative factors. Notably, the model demonstrated versatility by filling missing values in the dataset with Compressor discharge pressure (CDP) and Outlet Temperature (OT) predictions. The proposed framework intends to illustrate the practical application of predictive analytics in the sustainable energy/oil and gas industry to give significant insights into the variables influencing energy output and its potential for boosting operational efficiency and cost-effectiveness in power generation. The proposed research establishes the framework for real-time integration of the developed XGBoost model with gas turbine control systems.

Recommended practice for quantifying the energy resource at a tidal energy site requires the use of multiple instruments deployed across the site. However, the instruments used work by emitting an acoustic pulse and instruments working at the same time have the potential to interfere with each other through a process known as ’cross-talk’. It is important to understand the impact of cross-talk on measurements and how this can be managed and through data processing or suitable positioning of devices. The ReDAPT project conducted a measurement campaign using two Acoustic Doppler Current Profilers (ADCPs) placed upstream of an operational tidal turbine. This aimed to assess the ’in-line’ instrument placement guidelines from IEC 62600-200 for Power Performance Assessment (PPA) in real-world conditions. Consequently, the results within hold potential to support arguments for expanding these zones or adjusting their general dimensions. Despite adhering to industry standards and best practices to eliminate unreliable data in the Quality Control (QC) checks, in both concurrently measuring ADCPs at different time stamps in approximately 15 % of the returned data. This work identified for the first time interference throughout the campaign and quantified subsequent impact on estimates. A method to remove data anomalies caused by interference between closely positioned ADCPs has been developed and demonstrated, resulting in a 7 % variation in estimated Annual Energy Production (AEP). The algorithm effectively removed approximately 90 % of the corrupted measurements. Moving forward, multi-sensor deployments could use the algorithm described to double-check for interference within the data sets, although care should be taken to avoid this by choosing a suitable layout for deployment.

Abstract This work presents experimental results on the energy efficiency in hydrogen production using atmospheric microwave plasma (915 MHz) through steam reforming of ethanol. Ethanol was chosen as a liquid hydrogen carrier due to its high hydrogen atom content, low cost, and wide availability. The experimental work began with the maximization of an energy efficiency of the used microwave plasma source. The process of maximization involved determining a position of a movable plunger that ensures the most efficient transfer of microwave energy from a microwave source to the generated plasma in the microwave plasma source. The aim of the investigations was to test the following working conditions of the microwave plasma source: absorbed microwave power P A by the generated plasma (up to 5.4 kW), the carrier gas volumetric flow rate (up to 3900 Nl/h), and the amount of the introduced ethanol vapours on the efficiency of hydrogen production (up to 2.4 kg/h). In the range of tested working conditions, the highest energy yield for hydrogen production achieved a rate of 26.9 g(H2)/kWh, while the highest hydrogen production was 99.3 g(H2)/h.

Building-Integrated Photovoltaic (BIPV) on vertical façades is a potential PV application in today's buildings. The performance of BIPV on façades is significantly influenced by the façade orientation. For tropical cities, the optimum façade orientation, in terms of maximum energy yield and daylight performance, cannot be simply determined, due to relatively symmetrical sun path throughout the day. This study therefore aims to determine the optimum orientation for BIPV on tropical building façades. To achieve the objective, experiment, modelling, and computational simulation are conducted to evaluate the BIPV energy yield and to predict the indoor daylight performance in a scale-model building with a 105Wp monocrystalline silicon PV, facing each cardinal orientation in Bandung, Indonesia. The South orientation yields practically zero ASE1000,250, providing the best annual daylight performance, and yielding the most desirable value in four out of five daylight metrics. The greatest annual energy yield is at the North orientation, providing 179–186 kWh (95% prediction interval) per year, but with larger uncertainty compared to that at the South, due to direct sunlight occurrence. Based on three different objective functions, the South orientation is considered optimum for placing the BIPV panel on the prototype façade in the location.

This research explores the potential of electric field enforcement in dielectric barrier discharge using specially designed pyramid‐shaped μ‐electrodes for a plasma‐assisted nitrogen fixation process. The obtained results are compared under varying conditions, including the presence and absence of titanium dioxide (TiO2 ${TiO_2 }$), different oxygen concentrations in the nitrogen‐feeding gas, and residence time. The results demonstrate that the μ‐electrodes lead to an enhancement of nitrogen oxidation, which is further intensified by TiO2 ${TiO_2 }$. The introduction of 60–70 % oxygen with nitrogen achieves the highest level of NOX ${NO_X }$ production. The synergistic effect of plasma and the catalytic effect of TiO2 ${TiO_2 }$ increase the rate of NOX ${NO_X }$ production by 20 %, resulting in a 23 % increase in energy yield. The introduction of TiO2 ${TiO_2 }$ leads to a sharp increase in NOX ${NO_X }$ production even at lower oxygen concentrations. The crucial role played by ultraviolet light‐induced electron‐hole pairs in TiO2 ${TiO_2 }$ is highlighted to promote nitrogen oxidation. Nevertheless, it is crucial to emphasize that prolonged residence times may cause the photocatalytic effect to generate alternative byproducts rather than NOX ${NO_X }$ , consequence of excessive oxidation that could prove counterproductive. These findings emphasize the potential of plasma‐assisted nitrogen fixation technology in reducing energy costs and meeting the growing demand for sustainable nitrogen‐based fertilizers. [ABSTRACT FROM AUTHOR]

Building-Integrated Photovoltaic (BIPV) on vertical façades is a potential PV application in today's buildings. The performance of BIPV on façades is significantly influenced by the façade orientation. For tropical cities, the optimum façade orientation, in terms of maximum energy yield and daylight performance, cannot be simply determined, due to relatively symmetrical sun path throughout the day. This study therefore aims to determine the optimum orientation for BIPV on tropical building façades. To achieve the objective, experiment, modelling, and computational simulation are conducted to evaluate the BIPV energy yield and to predict the indoor daylight performance in a scale-model building with a 105Wp monocrystalline silicon PV, facing each cardinal orientation in Bandung, Indonesia. The South orientation yields practically zero ASE 1000,250, providing the best annual daylight performance, and yielding the most desirable value in four out of five daylight metrics. The greatest annual energy yield is at the North orientation, providing 179-186 kWh (95% prediction interval) per year, but with larger uncertainty compared to that at the South, due to direct sunlight occurrence. Based on three different objective functions, the South orientation is considered optimum for placing the BIPV panel on the prototype façade in the location. [ABSTRACT FROM AUTHOR]

Copyright of Informacije MIDEM: Journal of Microelectronics, Electronic Components & Materials is the property of MIDEM Society 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.)

Plasma-assisted nitrogen fixation has emerged as a promising alternative to conventional nitrogen fixation methods. In this study, we investigate the feasibility of plasma-assisted nitrogen fixation using an AC-driven dielectric barrier discharge generated from the micro-tips of a specially designed fast-modulated pyramid-shaped electrode. The obtained result is compared with the conventional flat electrode. Our results demonstrate that pyramid-shaped micro-tip electrodes can excite more nitrogen molecules than flat electrodes. Thus, pyramid electrodes have 58% more nitrogen oxides yield efficiency at 32% less energy cost. The highest nitrogen fixation is attained at 60% to 70% of oxygen concentration in nitrogen-feeding gas. These findings suggest that discharge through microtip is a promising and viable technology that could play a significant role in reducing the energy cost of the plasma-assisted nitrogen fixation method to meet the growing demand for sustainable nitrogen-based fertilizers. [ABSTRACT FROM AUTHOR]

The design of an effective fuzzy maximum power point tracking controller plays a crucial aspect in enhancing the photovoltaic system’s efficiency. This article aims to design and compare the performance of symmetric and asymmetric types of fuzzy controllers’ maximum power point tracking algorithms. Depending on the BP SX150S module’ power-voltage attributes at standard technical conditions, the input membership function parameters are derived. Moreover, the effect of fuzzy memberships’ quantity is also examined in this article. Where Five and seven triangular memberships are used. For the simulation, MATLAB is used to assess the effectiveness of the fuzzy controllers. Simulation results show that the asymmetric controller outperforms the symmetric type in terms of transient and steady-state tracking for different numbers of membership functions. Specifically, when employed with 5-triangle memberships, the asymmetric controller outperforms the symmetrical controller in terms of rise time, tracking precision, and energy output, respectively, by 83%, 0.06%, and 14.14%. While, the rise time, tracking precision, and energy yield of 7-triangle memberships are all improved by 86.7%, 0.04%, and 14.78%, respectively. Using asymmetric type, 7-triangle memberships enhance the rise time and harvested energy by around 18.2% and 0.082%, respectively. Overall, the most effective tracking technique for enhancing the photovoltaic system’s efficiency is the asymmetric type, independent of the quantity of memberships. [ABSTRACT FROM AUTHOR]

In the past four years, the number of prosumers utilizing photovoltaic (PV) installations in Poland has increased significantly, exceeding 1.3 million, reaching a total power capacity of 10.5 GW by the end of 2023. This paper presents a three-year energy yield analysis of the prosumer PV systems operating in Eastern Poland. The 9.6 kW system consists of high-efficiency monocrystalline photovoltaic modules in half-cut technology. Over the three years of operation, specific yields have been analyzed along with weather parameters, such as solar intensity, outdoor temperature, humidity, wind speed, rainfall, or snowfall. The average annual final yield was found to be relatively high, exceeding 1000 kWh·kW−1 in each of the analysed years. The highest monthly specific yields of the analysed period were noticed during the summer, reaching the maximum value of 164 kWh·kW−1 in 2022. The daily final yields varied from a minimum of 0.15 kWh·kW−1 in Winter 2021 to a maximum of 6.8 kWh·kW−1 in Spring 2022. Weather conditions increasing the energy yields, such as low average ambient temperatures together with high insolation periods, were noticed. Energy production in such favorable conditions reached a surprisingly high value of energy yield in April 2020, comparable to the summer months (151.0 kWh·kW−1). The occurrence of heavy rainfall in summer was also noted as a desirable effect that leads to the natural cleaning of the PV modules. The average performance ratio during the analyzed period was found to be 0.85. The energy production of the PV system allowed the reduction of about 21 tons of CO2 emission. [ABSTRACT FROM AUTHOR]

The yearly energy yield of a Solar Photovoltaic (SPV) system is a rendition pointer utilized by the erector to determine the output energy generated by it. From the energy speculation, the payback period and the return on investment can be contemplated. The system energy yield formula consists of many parameters, the most important of which is the SPV inverter efficiency. The European and peak (maximum) efficiency factors from the inverter data sheet are typically utilized, but this utilization is unsound because the SPV does not always work at the peak of its effectiveness due to varying irradiance. The inverter's weighted efficiency is considered more sound as it deems the inverter output power peculiarities. The European weighted efficiency is the most widely accepted inverter efficiency determination. Since it is derived and documented on a rimmed European irradiance profile, it may not be appropriate for inverters constructed in different climatic conditions, especially in the equatorial and subtropical environmental regions. This work aims to formulate a fangled weighted efficiency equation for the inverter's work in the Iraqi environment (especially in Baghdad city as a case study) documented on the IEC 61683: 1999 Standard and Irradiance-Duration curve. The sophisticated formula is endorsed on experimental data from the field using an SMA-SB-4000-TL inverter. It was found that the speculated energy yield using the derived efficiency formula for the Baghdad environment closely matches the energy yield of an original 4.0 KW SPV inverter system with only 1% difference between the determined and acquired values. This means that the employment of the Baghdad weighted efficiency in place of the European or peak weighted efficiency will result in a sounder speculation of the system energy yield, return on investment, and payback duration of the SPV system project. [ABSTRACT FROM AUTHOR]

This study investigated the torrefaction of durian peel using air and nitrogen as carrier gases. A multilevel factorial design coupled with response surface methodology (RSM) and ANOVA analysis was employed to analyze the impact of torrefaction parameters on chemical properties and energy yield. Durian peel, an agricultural waste product, was torrefied at temperatures ranging from 200 to 320 °C for residence times between 0 and 30 min. Results showed that air torrefaction significantly enhanced thermal decomposition, reducing mass yield from 94.65 % to 30.63 % as the temperature increased from 200 °C to 300 °C with a 30-min holding time. Air torrefaction also increased the higher heating value (HHV) from 19.02 MJ/kg to 35.26 MJ/kg at 300 °C, compared to nitrogen, which achieved a maximum HHV of 32.49 MJ/kg. ANOVA analysis revealed that torrefaction temperature and carrier gas significantly affect energy yield and chemical properties. Air torrefaction positively affected HHV while reducing mass yield compared to nitrogen. Low-temperature air torrefaction showed enhanced energy yield improvement. These findings provided insights for optimizing torrefaction processes enhancing utilization wasted durian peel as a sustainable bioenergy resource.

Food waste (FW) is a significant global issue with a carbon footprint of 3.3 billion tonnes (Bt), primarily generated due to improper food supply chain management, storage issues, and transportation problems. Acidogenic processes like dark fermentation, anaerobic digestion, and a combination of DF-AD can produce renewable biofuels (Bio-CH4, Bio-H2) by valorising FW, aligning with the UN SDGs. FW is an ideal substrate for acidogenic processes due to its high moisture content, organic matter, and biodegradability. However, the choice of FW valorisation pathways depends on energy yield, conversion efficiency, and cost effectiveness. Acidogenic processes are not economically viable for industrial scale FW treatment due to reduced energy recovery from stand-alone processes. So, this study reviews comparative studies on biogas, biohydrogen, and biohythane production from FW via acidogenic processes, focusing on energy yield, energy recovery, and environmental and economic impact to provide a clear understanding of energy recovery and yield from all acidogenic processes. Additionally, this review also explores the recent advancements in digestate slurry management and the synergistic effects of AD and HTC processes. Lastly, a futuristic integrated bio-thermo-chemical process is proposed for maximum energy recovery, valuing food waste to energy vectors (Bio-H2, Bio-CH4, and hydro-char) along with digestate management and biofertilizer production. [ABSTRACT FROM AUTHOR]

The reuse potential for the large annual production of spent coffee grounds (SCGs) is underexploited in most world regions. Hydrochars from SCGs produced via hydrothermal carbonization (HTC) have been recognized as a promising solid fuel alternative. To increase demand, optimization of the HTC and two post-treatment processes, washing and agglomeration, were studied to improve hydrochar in terms of energetic properties, minimizing unwanted substances, and better handling. HTC experiments at three scales (1–18.75 L) and varying process conditions (temperature T (160–250 °C), reaction time t (1–5 h), and solid content %So (6–20%) showed that the higher heating value (HHV) can be improved by up to 46%, and most potential emissions of trace elements from combustion reduced (up to 90%). The HTC outputs (solid yield—SY, HHV, energy yield—EY) were modeled and compared to published genetic programming (GP) models. Both model types predicted the three outputs with low error (<15%) and can be used for process optimization. The efficiency of water washing depended on the HTC process temperature and type of aromatics produced. The furanic compounds were removed (69–100%; 160 °C), while only 34% of the phenolic compounds (240 °C) were washed out. Agglomeration of both wet SCG and its hydrochar is feasible; however, the finer particles of washed hydrochar (240 °C) resulted in larger-sized spherical pellets (85% > 2000–4000 µm) compared to SCGs (only 4%). [ABSTRACT FROM AUTHOR]

In addition to food production, energy can also be produced on agricultural land. This can lead to land use conflicts and often results in political discussions. As the energy transition progresses, the area required for renewable energies is increasing, leading to more land use conflicts. Agrivoltaics (APV) allows for continued farming alongside solar power production, providing a solution to this conflict. In this analysis, the land energy yields of different APV concepts were compared with those of other renewable energies. The results show that wind and PV can produce the most energy on land, regardless of whether the sectors are electricity, heat or transport. When considering different APV concepts on cropland, it is important to consider which area is being evaluated. A distinction can be made between the PV-system area (the visually influenced area in the landscape) and the loss of farmland. Depending on the perspective, the concepts have different advantages. The APV vertical concept enables 3 times more electricity production per loss of farmland compared to a conventional ground-mounted PV system. However, in relation to the PV-system area, the electricity yield is only 1/3 of this. The APV horizontal concept has the highest electricity yields per area of loss of farmland. The APV 3D tracing system has the highest electricity yield of all APV concepts per PV-system area. Initial economic analyses show that higher energy yields per loss of farmland are accompanied by higher costs for APV systems. These results can be used for political advice.

The design of an effective fuzzy maximum power point tracking controller plays a crucial aspect in enhancing the photovoltaic system’s efficiency. This article aims to design and compare the performance of symmetric and asymmetric types of fuzzy controllers’ maximum power point tracking algorithms. Depending on the BP SX150S module’ power-voltage attributes at standard technical conditions, the input membership function parameters are derived. Moreover, the effect of fuzzy memberships’ quantity is also examined in this article. Where Five and seven triangular memberships are used. For the simulation, MATLAB is used to assess the effectiveness of the fuzzy controllers. Simulation results show that the asymmetric controller outperforms the symmetric type in terms of transient and steady-state tracking for different numbers of membership functions. Specifically, when employed with 5-triangle memberships, the asymmetric controller outperforms the symmetrical controller in terms of rise time, tracking precision, and energy output, respectively, by 83%, 0.06%, and 14.14%. While, the rise time, tracking precision, and energy yield of 7-triangle memberships are all improved by 86.7%, 0.04%, and 14.78%, respectively. Using asymmetric type, 7-triangle memberships enhance the rise time and harvested energy by around 18.2% and 0.082%, respectively. Overall, the most effective tracking technique for enhancing the photovoltaic system’s efficiency is the asymmetric type, independent of the quantity of memberships.

This study analyzes the field performance of various solar cell designs. Most research and development efforts concerning solar cells aim to increase their efficiency or power under standard test conditions (STC). However, conducting an actual field performance analysis is crucial because of the various ambient conditions present in the field, including temperature, irradiance, PV system installation, and albedo. These conditions can result in different performance results compared to STC. This study compares and analyzes case studies to assess field performance. One particular case study compares the field performance of monofacial modules with a monofacial passivated emitter and rear cell (PERC) and bifacial PERC at a carport system in the ambient conditions of the Korean Peninsula during summer and winter. The module material properties (white EVA and white backsheet) can impact module performance owing to the transmittance spectra at longer wavelengths. Certain transmittance values also contribute to the bifaciality number. Although the monofacial cell demonstrates better STC results, the field performance of the bifacial cell is superior in terms of energy yield and cost-effectiveness. Therefore, this study highlights the importance of considering the field performance (energy yield), in addition to STC, when designing solar cells and modules.

In the photovoltaic (PV) industry, module manufacturers have begun to install bifacial cells into monofacial modules because of their lower production costs relative to monofacial cells. This is linked mainly to a 65.3% reduction in rear aluminum paste consumption and the corresponding 0.5 cent/wafer cost reduction for M4 (161.7 × 161.7 mm2) size wafers. Therefore, this study compared the performance of monofacial PV modules with the monofacial cells as a reference group and bifacial cells as the test group to determine the cost reduction potential of the latter in terms of energy yield. Fifteen modules of each type were installed in a solar carport system on the Korean Peninsula and recorded irradiance and ambient and module temperature for one year. Throughout the year, irradiance and energy yield exhibited a strong linear correlation. The total annual energy yields of the monofacial and bifacial cells were 1,093.1 and 1,098.9 kWh/kWp, respectively. The energy yield of the bifacial module was 5.8 kWh/kWp (0.53%) higher than that of the monofacial module. Thus, monofacial modules with bifacial cells may be used in the PV industry to reduce cell production costs and levelized cost of electricity while enhancing energy yields and overall product performance in carport systems on the Korean Peninsula during all four seasons.

Abstract As photovoltaic modules are increasingly used in renewable energy systems, ensuring energy efficiency by reducing the levelized cost of electricity has become the focus of current research. Herein, the 1‐year performances of both monofacial and bifacial photovoltaic modules were monitored, compared, and analyzed at a solar carport system in the Korean peninsula. The environmental parameters during the four seasons were investigated for both systems under ambient conditions. Irradiance was determined as the primary influencing parameter in the system. The energy yield of the bifacial module system was 3.08% higher than that of the monofacial system owing to rear‐side absorption during the study period. The loss mechanism for this lower yield was determined by investigating the irradiance effect. It was attributed to low bifaciality due to cell properties (optical and electrical properties, and the sorting effect) and module properties (shading effects from the junction box cable and frame design, and glass grid effect), design of the carport system, and the albedo effect. These analyses revealed that the photovoltaic energy yield can be increased further by reducing these loss parameters at the carport system. This study can contribute to achieving higher energy yield from photovoltaic systems during field applications.

The atomic bomb uses fission of heavy elements to produce a large amount of energy. It was designed and deployed during World War II by the United States military. The first test of an atomic bomb occurred in July 1945 in New Mexico and was given the name Trinity; this test was not declassified until 1949. In that year, Geoffrey Ingram Taylor released two papers detailing his process in calculating the energy yield of the atomic bomb from pictures of the Trinity explosion alone. Many scientists made similar calculations concurrently, although Taylor is often accredited with them. Since then, many scientists have also attempted to calculate a yield through various methods. This paper walks through these methods with a focus on Taylor’s method—based on first principles—as well as redoing the calculations that he performed with modern tools. In this paper, we make use of state-of-the-art computer vision tools to find a more precise measurement of the blast radius, as well as using curve fitting and numerical integration methods. With more precise measurements we are able to follow in Taylor’s footstep toward a more accurate approximation.

Wind power is an important energy source that can be used to supply clean energy and meet current energy needs. Despite its advantages in terms of zero emissions, its main drawback is its intermittency. Deterministic approaches to forecast wind power generation based on the annual average wind speed are usually used; however, statistical treatments are more appropriate. In this paper, an intelligent statistical methodology to forecast annual wind power is proposed. The seasonality of wind is determined via a clustering analysis of monthly wind speed probabilistic distribution functions (PDFs) throughout n years. Subsequently, a methodology to build the wind resource typical year (WRTY) for the n + 1 year is introduced to characterize the resource into the so-called statistical seasons (SSs). Then, the wind energy produced at each SS is calculated using its PDFs. Finally, the forecasted annual energy for the n + 1 year is given as the sum of the produced energies in the SSs. A wind farm in Mexico is chosen as a case study. The SSs, WRTY, and seasonal and annual generated energies are estimated and validated. Additionally, the forecasted annual wind energy for the n + 1 year is calculated deterministically from the n year. The results are compared with the measured data, and the former are more accurate. [ABSTRACT FROM AUTHOR]

Forest residues have been gaining interest as a source of renewable fuels due to their availability and the risks they represent for increasing forest fires. A major drawback for their removal and processing is the cost of transportation, which can be overcome through densification procedures, e.g., torrefaction. To optimize the torrefaction parameters, Cistus ladanifer residues from the Portuguese forest were torrefied for 30 min in a lab-scale reactor at 250 and 350 °C. The quality of the torrefied material was assessed, and its energy and mass yields were determined through thermal analysis. The changes in morphological structure occurring during torrefaction were analysed through scanning electron microscopy. When compared to the original biomass, the charcoal obtained at 350 °C had a substantial increase in energy density accompanied by a significant mass reduction. Increasing the mass in the reactor had a positive effect on the energy yield. For the highest mass tested, a mass reduction of around 30% was obtained and a char with no loss in energy content (with a cumulative heat flow (CHF) of 9.0 MJ/kg compared to 5.8 MJ/kg of the original biomass). Modelling of the reactor allowed the analysis of the heat profile required for torrefaction. [ABSTRACT FROM AUTHOR]

The photovoltaic (PV) module energy rating standard series IEC 61853 does not cover bifacial PV modules. However, the market share of bifacial PV modules has dramatically increased in recent years and is projected to grow. This work demonstrates how Parts 3 and 4 of the IEC 61853 standard could be extended to bifacial modules. First, we develop an irradiance model that uses the data already given in the standard IEC 61853‐4 to calculate the irradiance on the rear side of the module. Second, we propose a way to extend the energy yield calculation algorithm IEC 61853‐3 to include bifacial modules and make it available to the PV community. This rear irradiance and bifacial energy yield calculation procedure is tested using real outdoor measurements for a nine‐month period with a root mean square difference between measured and simulated energy yield of 4.65%. To conclude, we investigate the impact of different climates and normalization on the bifacial module energy rating results. [ABSTRACT FROM AUTHOR]

Compared with typical mono-facial photovoltaic (PV) solar modules, bifacial solar modules can make full use of reflected or scattered light from the ground and the surroundings to yield more electrical energy. The electrical energy on the rear side depends on multiple factors, such as the IV parameters of modules, packaging materials, and installation circumstances. In this work, the power generation output is simulated and researched using the PV-SYST software program, based on the different electrical parameters of bifacial solar modules and the installation conditions of the given PV systems. The influencing factors that affect the electrical energy are further analyzed using power-loss diagrams. The results show that improving the surface albedo can raise additional energy by 8.3%, thus behaving significantly better than the mono-facial module. Furthermore, improving the siting height and incidence angle modifier (IAM) of the modules can increase the additional energy by 3.1%. In contrast, adjusting the output current or voltage of the modules adds some energy, while the modules are of the same nominal power value. It was observed that the energy level of a photovoltaic system mainly depends on the installation circumstances, but the electrical parameters of the modules themselves contribute little. [ABSTRACT FROM AUTHOR]

Biomass is a renewable alternative energy source with almost zero‐carbon footprint. This work focused on the physicochemical analysis and wet torrefaction of shea nut chaff (SNC) biomass. The SNC is a semi‐solid waste generated during the production process of shea nut butter and is least studied for its bioenergy potential. Wet torrefaction or hydrothermal carbonization studies of sun‐dried SNC were conducted at different temperatures (180–260°C), residence times (15–30 min) and water‐to‐biomass (W/B) ratios (5–15:1). Characterization studies of the torrefied biomass for different temperatures were conducted using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM) analyses. The best‐fit analysis of variance (ANOVA) model for wet torrefaction mass yield was 2FI, with p‐values of <0.05, and a regression coefficient (R2) of 0.9443. The yield of torrefied SNC attained at 260°C, 45 bar, W/B ratio of 5, and 10‐min residence time was 55.5 wt.%, and the corresponding energy yield was 89.5%. Both temperature and W/B ratio had significant effect on torrefaction yield. There was a significant improvement in the volatile matter, fixed carbon, moisture, and heating value reduction in the torrefied SNC compared to the raw SNC making it a potential bioenergy source. However, high ash content is a major concern even after torrefaction. [ABSTRACT FROM AUTHOR]

In this work, the thermochemical properties of municipal solid waste (MSW) are studied using the torrefaction process as the main method for investigation. Torrefaction experiments were carried out using an electric laboratory furnace, at temperatures of 200, 250, and 300 °C. The residence time was set to 90 min. Proximate and ultimate analysis were performed on the torrefied MSW samples and compared with the properties of the raw MSW samples. In addition, the thermal properties of the obtained torrefied MSW samples were evaluated by thermogravimetric analysis (TGA) and derivative thermogravimetric analysis (DTG). The following could be stated: the obtained results showed that mass and energy yields (MY and EY, respectively) decrease with increasing when torrefaction temperature, while the heating values (HHV) increased under the same conditions (from 24.3 to 25.1 MJ/kg). Elemental analysis showed an increase in carbon content (C), from 45.7 ± 0.9 to 52.8 ± 1.05 wt.%, and decrease in oxygen content (O), from 45.6 ± 0.9 to 39.5 ± 0.8 wt.%, when torrefaction temperature is increased, which is consistent with the general definition of the torrefaction process. In addition, enhancement factors (EFs) and fuel ratios (FRs) were calculated, which ranged from 1.00 to 1.02 and 0.16 to 0.23, respectively. Some anomalies were observed during the thermal analysis, which are assumed to be related to the composition of the selected MSW. This study therefore shows that torrefaction pretreatment can improve the physicochemical properties of raw MSW to a level comparable to coal, and could contribute to a better understanding of the conversion of MSW into a valuable, solid biofuel.

The temperature experienced by reactants during preparation in a reactor is a key component in determining the yield and homogeneity of usable chemical products such as biomass particles. Thermocouples with sensors can be used to monitor spatial temperature gradients within reactors but these sensors are often too expensive and/or invasive. The present work proposes a strategy to identify optimal machine learning models to infer the maximum effective temperature experienced by particles during oxidative biomass torrefaction using key thermochemical combustion parameters. The maximum rate of weight loss, the corresponding temperature, and fixed carbon content on a dry‐ash‐free basis are used as literature‐based predictor variables obtained from thermogravimetric analysis. The evaluation of 24 machine‐learning models using the standard tenfold cross‐validation method suggests that the exponential Gaussian process regression (GPR) model is the most effective, followed by other GPR models. These high‐performing GPR models were also utilized to predict the effective preparation temperature distribution of reactor‐produced biomass particles under eight conditions of varying residence time and air‐to‐biomass ratio. The effective preparation temperature and residence time of individual biomass particles were then encoded into the torrefaction severity factor and used to estimate the energy yield of the reactor output as a novel quality control method. © 2023 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Crop diversification in rotations is an important part of sustainable crop production. The aim of this research was to analyse soil tillage and crop rotation influence on the yield (t ha−1) of different field crops, their energy yield (GJ ha−1) and the economical profitability (EUR ha−1) of crop rotation. The field trial was conducted in Latvia during four harvest seasons (2017–2020) in a long-term experiment that started in 2009. Three crop rotations with a different share of winter wheat (Triticum aestivum) were studied: 100% wheat (repeated sowings), 67% wheat (three-year rotation with winter oilseed rape (Brassica napus ssp. oleifera) and two years following wheat) and 25% wheat (four-year rotation: field bean (Vicia faba)–wheat–winter oilseed rape–spring barley (Hordeum vulgare). Conventional and reduced soil tillage systems were used for rotation variants. Crop rotations "67% wheat" and "25% wheat" ensured significantly higher average wheat grain yields in comparison to "100% wheat". Wheat and oilseed rape were the most valuable crops in terms of accumulated energy and economic value in this trial. Higher energy yields were gained from variants in the rotations "67% wheat" and "25% wheat". Average gross profit was higher from crop rotations with diverse crops, mainly due to the positive forecrop effect on winter wheat. [ABSTRACT FROM AUTHOR]

Demonstrating power performance in real conditions is vital for verifying tidal turbine design. The International Electrotechnical Commission's Technical Specification IEC TS 62600-200 provides guidance for tidal developers to evaluate machine performance. This study evaluates the performance of the operational 1 MW DEEP-Gen IV commercial-scale tidal turbine deployed during the ReDAPT project at the European Marine Energy Centre's tidal test site in Orkney, Scotland. IEC TS 62600-200 states that the power performance should be measured relative to two independently located current profilers deployed in one of two orientations; 'in-line' (preferred) or 'adjacent' (least preferred), relative to the turbine. Two measurement campaigns are used to assess the impact of instrument placement on the measured power curve and annual energy production (AEP). The ambient current flow and vertical profile form differed at each current profiler location (due to topography and bathymetry), leading to AEP variability. The results reinforce the IEC TS preferred orientation for instrument placement, with inline measurements showing smaller variation in AEP estimates compared with adjacent measurements. An additional analysis assesses the sensitivity of AEP estimates on the vertical alignment of the flow profiles with rotor positioning. For this we consider three turbine scenarios: the DEEP-Gen IV and two modelled turbine rotors occupying different regions in the water column. Results show that for regions of high vertical shear, AEP estimates can be misrepresented by up to 5.5% under an imposed vertical misalignment of 2 m. This work has quantified, at this site, the variation in AEP estimates from different flow measurement campaigns informed by IEC TS 62600-200 and has shown the need to ensure good vertical alignment between measurements and turbine rotor positioning. • The measured power curve for TEC is sensitive to the flow reference used. • ADCPs placed in-line to the TEC provide a better reference than adjacently placed. • In-line flow measurements varied despite being placed at IEC prescribed distance. • Large flow structures impacted measurements 30 m from the TEC location. • Vertical ADCP misalignment (±2 m) to TEC swept area can impact AEP by up to 5.5%. [ABSTRACT FROM AUTHOR]

As photovoltaic modules are increasingly used in renewable energy systems, ensuring energy efficiency by reducing the levelized cost of electricity has become the focus of current research. Herein, the 1‐year performances of both monofacial and bifacial photovoltaic modules were monitored, compared, and analyzed at a solar carport system in the Korean peninsula. The environmental parameters during the four seasons were investigated for both systems under ambient conditions. Irradiance was determined as the primary influencing parameter in the system. The energy yield of the bifacial module system was 3.08% higher than that of the monofacial system owing to rear‐side absorption during the study period. The loss mechanism for this lower yield was determined by investigating the irradiance effect. It was attributed to low bifaciality due to cell properties (optical and electrical properties, and the sorting effect) and module properties (shading effects from the junction box cable and frame design, and glass grid effect), design of the carport system, and the albedo effect. These analyses revealed that the photovoltaic energy yield can be increased further by reducing these loss parameters at the carport system. This study can contribute to achieving higher energy yield from photovoltaic systems during field applications. [ABSTRACT FROM AUTHOR]

Bifacial perovskite (PVK)/crystalline silicon (c‐Si) tandem photovoltaic (PV) modules provide an effective strategy to further improve the efficiency and energy yield (EY) of c‐Si PV modules. In this work, the energy outputs of bifacial tandem PV modules under outdoor conditions are analyzed by combining optical modeling, one‐diode equivalent circuit model, module tilt angle, and meteorological data, and a detailed comparative study with bifacial silicon heterojunction (SHJ) PV modules is also performed. The bifacial PVK/c‐Si tandem modules exhibit higher EY in locations with strong direct normal irradiance regardless of the ground type with any albedo, while bifacial SHJ modules exhibit similar or even higher EY than tandem modules in locations with strong diffuse horizontal irradiance (DHI) such as Chengdu. Considering factors such as EY and levelized cost of electricity, Eg_PVK in the range of 1.58–1.62 eV is suitable for most application scenarios, while the deployment of bifacial SHJ PV modules is preferred in areas dominated by DHI, as represented by Chengdu. Herein, important implications for policy making in determining the cost‐effective type of PV modules are provided to generate renewable electricity. [ABSTRACT FROM AUTHOR]

Harnessing the abundant solar resources holds great potential for sustainable energy generation. This research paper delves into a comprehensive analysis of seasonal tilt and solar tracking strategy scenarios for a 15 MW grid-connected PV solar power plant situated in Kandahar province, Afghanistan. The study investigates the impact of fixed tilt, seasonal tilt, SAHST (single-axis horizontal solar tracking), and SAVST (single-axis vertical solar tracking) on energy yield, considering technical, economic, and environmental aspects. In the first scenario, a fixed tilt angle of 31 degrees was employed. The second scenario explored the use of seasonal tilt angles, with a summer tilt angle of 15 degrees and a winter tilt angle of 30 degrees. The third scenario analyzed SAHST. Finally, the fourth scenario focused on implementing SAVST. SAVST proved to be an exceptional solution, showcasing a remarkable increase in annual energy yield, and generating an additional 6680 MWh/year, 6336 MWh/year, and 5084 MWh/year compared to fixed, seasonal, and SAHST scenarios, respectively. As a result, surplus energy yielded an income of USD 554,440.00 per year compared to fixed tilt. However, the investment cost for the solar tracking system amounted to USD 1,451,932, accompanied by an annual operation and maintenance cost of 0.007 USD/W/year. The analysis revealed a promising payback period of 3 years, confirming the economic feasibility of this investment. The findings underscore the effectiveness of different strategies for optimizing solar power generation in the Kandahar region. Notably, the installation of SAVST emerged as an influential solution, significantly increasing power production. These research outcomes bear practical implications for solar tracking strategies for addressing the load challenges faced by Kandahar province and offer valuable insights for the operators and operation of solar power plants in similar regions. [ABSTRACT FROM AUTHOR]

Developing countries like India are rapidly transitioning from traditional energy sources to sustainable energy sources, due to the increase in demand and the depletion of fossil fuels. Grid-connected photovoltaic (PV) systems attract many investors, organizations, and institutions for deployment. This article studies and compares the performance evaluations of three 52-kW PV plants installed at an educational institution, SRMIST (SRM Institute of Science and Technology), in Tamil Nadu, India. This site receives an annual average temperature of 28.5°C and an average global horizontal irradiation of 160 kWh/m2/m. The prediction model for the 52-kW power plant is obtained using solar radiation, temperature, and wind speed. Linear regression model-based prediction equations are derived using the Minitab 16.2.1 software, and the results are compared with the real-time AC energy yield acquired from the three 52-kW plants for the year 2020. Furthermore, this 52-kW plant is designed using PVsyst V7.1.8 version software. The simulation results are compared with the energy yield from the plants in 2020 to identify the shortfall in the plant performance. The loss analysis for the plant is performed by obtaining the loss diagram from the PVsyst software. This study also proposes a methodology to study the commissioned PV plant’s performance and determine the interaction between variables such as direct and diffused solar radiations, air temperature, and wind speed for forecasting hourly produced power. This article will motivate researchers to analyze installed power plants using modern technical tools.

Abstract Wet dust on the Photovoltaic (PV) surface is a persistent problem that is merely considered for rooftop based PV cleaning under a high humid climate like Malaysia. This paper proposes an Automated Water Recycle (AWR) method encompassing a water recycling unit for rooftop PV cleaning with the aim to enhance the electrical performance. This study makes a major contribution by developing a new model to correlate output power ( $$P_{out}$$ P out ) and dust-fall factor. For model validation, we conducted an experiment of taking one set of Monocrystalline PV (mono) on a $$340\frac{W}{m^{2}}$$ 340 W m 2 of medium luminance day. One mono module was cleaned by AWR - pressurized water sprayed through 11 small holes over its front surface, while the other module was left with no-cleaning. The dust-contaminated water was filtered and collected back to the tank for recycling process. The water loss per cleaning cycle was achieved 0.32%, which was normalized to net loss of 28.8% at a frequency of 1 cycle/day for 90 days of operation. We observed that $$P_{out}$$ P out of no-cleaning PV was decreased by 29.44% than that of AWR method. From this experimental data also, a unique and more accurate model is created for $$P_{out}$$ P out prediction, which is much simpler compared to multivariables equation. Our investigation offers important insights into the accuracy of this regression model demonstrated by $$R^{2}=0.744$$ R 2 = 0.744 or a strong negative quadratic relationship between $$P_{out}$$ P out and dust-fall. The cleaning of PV modules is expected to save significant energy to reduce the payback period. Article Highlights An automated water recycle method for cleaning dust-fall in rooftop photovoltaic module is proposed. Both simulation and experimental models are developed to predict output power of the photovoltaic module. Proposed method can produce 24.40% more output power than a no-cleaning system with a mere water loss of 0.32%/cycle.

The incorporation of photovoltaic elements in buildings have been gaining more mileage in recent times. Building integrated photovoltaic (BIPV) technologies are on the rise in terms of efficiency and longevity, with a compound annual growth rate (CAGR) of 15.7 % since 2018. The costs of production and raw materials of BIPV have reached a level that is economically beneficial for building developers to adopt the technology. However, the lack of infrastructure as compared to traditional means of energy production has impeded the maturing of such technologies. The issue of conversion efficiency and module degradation have been addressed but not completely resolved by the scientific community. Although attractive governmental incentives such as net energy metering (NEM) and better returns of investments are shifting the tide as of late, what remains to be seen is the mass adoption of BIPV technology in residential and commercial infrastructure. This work aims to develop an optimal layout for photovoltaic panels in the university building precise 3D modelling and solar energy resource assessment. The method adopted is based on energy production capability of a 3D modelled BIPV system which will be carried out in three stages. They are i) Assessment of geographical location and meteorological data, ii) Development of 3D model and orientation analytics and (iii) Development of optimal PV layout. Three systems were considered for this study, which is the roof and two systems on the Southern Façade. The proposed rooftop BIPV design is expected to provide 49.27 % of the building's energy consumption while reducing CO2 emissions by 20155.32 tonnes throughout the lifespan of the system's deployment. This paper serves as a pioneering study on the feasibility of a BIPV system through the incorporation of building geometry for computations on incident solar irradiation. Through the reduction of electricity imported from the grid, the adoption of the BIPV system also serves as an incremental step towards achieving Net Zero Energy Building (NZEB) status for HWUM.

In this work, the thermochemical properties of municipal solid waste (MSW) are studied using the torrefaction process as the main method for investigation. Torrefaction experiments were carried out using an electric laboratory furnace, at temperatures of 200, 250, and 300 °C. The residence time was set to 90 min. Proximate and ultimate analysis were performed on the torrefied MSW samples and compared with the properties of the raw MSW samples. In addition, the thermal properties of the obtained torrefied MSW samples were evaluated by thermogravimetric analysis (TGA) and derivative thermogravimetric analysis (DTG). The following could be stated: the obtained results showed that mass and energy yields (MY and EY, respectively) decrease with increasing when torrefaction temperature, while the heating values (HHV) increased under the same conditions (from 24.3 to 25.1 MJ/kg). Elemental analysis showed an increase in carbon content (C), from 45.7 ± 0.9 to 52.8 ± 1.05 wt.%, and decrease in oxygen content (O), from 45.6 ± 0.9 to 39.5 ± 0.8 wt.%, when torrefaction temperature is increased, which is consistent with the general definition of the torrefaction process. In addition, enhancement factors (EFs) and fuel ratios (FRs) were calculated, which ranged from 1.00 to 1.02 and 0.16 to 0.23, respectively. Some anomalies were observed during the thermal analysis, which are assumed to be related to the composition of the selected MSW. This study therefore shows that torrefaction pretreatment can improve the physicochemical properties of raw MSW to a level comparable to coal, and could contribute to a better understanding of the conversion of MSW into a valuable, solid biofuel. [ABSTRACT FROM AUTHOR]