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The rising demand for renewable energy sources has fueled interest in converting biomass and organic waste into sustainable bioenergy. This study employs a bibliometric analysis (2013-2023) of publications to assess trends, advancements, and future prospects in this field. The analysis explores seven key research indicators, including publication trends, leading contributors, keyword analysis, and highly cited papers. We begin with a comprehensive overview of biomass as a renewable energy source and various waste-to-energy technologies. Employing Scopus and Web of Science databases alongside Biblioshiny and VOSviewer for analysis, the study investigates publication patterns, citation networks, and keyword usage. This systematic approach unveils significant trends in research focus and identifies prominent research actors (countries and institutions). Our findings reveal a significant increase in yearly publications, reflecting the growing global focus on biomass and organic waste conversion. Leading contributors include China, the United States, India, and Germany. Analysis of keywords identifies commonly used terms like "biofuels," "pyrolysis," and "lignocellulosic biomass." The study concludes by proposing future research directions, emphasizing advanced conversion technologies, integration of renewable energy sources, and innovative modelling techniques.

Accurate determination of reaeration coefficient in lakes is a key factor for accurate modeling of dissolved oxygen. This study developed a new numerical model to determine the lake reaeration coefficient of Sawa lake, Iraq based on solving the transform mechanisms of dissolved oxygen without the using the empirical and laboratory methods. The model solved the gas transport at the water-air surface numerically to predict the dissolved oxygen and the reaeration coefficient simultaneously. Results showed that the lake reaeration coefficient was 0.001 Day-1 at 20 °C with low RMSEs (0.138, 0.137, and 0.168 mg/L for the three years of simulation 2007, 2012, and 2017, respectively) and AMEs (0.121, 0.114, and 0.145 mg/L in 2007, 2012, and 2017, respectively). It was noticed the lake habitat was impacted causing unhealthy conditions (low reaeration rate), and there is upward dissolved oxygen movement due to the presence of positive trend in the yearly cycle of temperature. In addition, including this numerical approach along with other water quality models can improve the predictions of other water quality parameters.

Jet impingement cooling enhances photovoltaic (PV) system efficiency by using high-speed fluid jets to reduce panel temperatures, improving performance and longevity. The effectiveness depends on factors like fluid flow rate, nozzle placement, and distance from the panel. While it boosts energy output, it may increase energy use for fluid circulation and add complexity to the system. This research explores a groundbreaking approach to enhancing the efficiency of bifacial photovoltaic thermal (BPVT) systems by integrating jet impingement technology. A novel design featuring a jet plate reflector is introduced, offering the dual benefit of cooling the PV panels while simultaneously reflecting light to optimize energy capture. The study comprehensively analyses the system’s performance, including energy output and a detailed techno-economic and environmental-economic evaluation. The modelling in this study was validated and reasonably consistent with experimental results. The system's output air temperature and thermal efficiency are 302.07–318.75 K and 33.83–62.28 %, respectively. The temperature and electrical efficiency range for PV systems are 304.39–339.54 K and 9.39–11.22 %. Reduced mass flow rate and increased solar irradiation are the most economically advantageous operating parameters for the proposed system, resulting in lower annual pumping costs and more significant annual energy gains for the system. CBR variations range from 0.1363 to 9.3445, with an average of 2. Additionally, by using BPVT with jet impingement to generate electricity rather than fossil fuels, it is possible to reduce annual carbon dioxide emissions by approximately 1.61 tons and save RM93.51 annually. In general, the proposed method should be used to minimize environmental pollution.

The use of solar photovoltaic panels as source of power for Brushless Direct Current (BLDC) motors requires a DC-DC Converter circuit. One application of solar energy is as a power source for Brushless Direct Current (BLDC) motors. The main problem is the voltage fluctuation and low DC voltage generated by the solar panel. This research aims to improve the performance of the DC-DC Boost Converter circuit and minimize voltage fluctuations. The methodology encompasses mathematical modeling of the circuit in the form of transfer functions and optimizing the DC-DC Boost Converter circuit using the Proportional Integral Derivative (PID) controller and the Firefly algorithm. Simulation testing results indicate an improvement in transient response performance of the DC-DC Converter circuit as a driver for the BLDC motor. This is evidenced by an increase in rise time from 499 s to 820 s, a decrease in settling time from 3.33 e+03 s to 2.07e+03 s, and a reduction in overshoot to 0 % from previously 11.4 %. The utilization of the firefly algorithm in optimization significantly enhances system efficiency, as demonstrated by faster achievement of stability without excessive oscillation and a reduction in the time required for the system to settle. Overall, this study shows that the firefly algorithm is effective in developing DC-DC Boost Converter circuits, improving system efficiency by reducing settling time and eliminating overshoot. These findings provide empirical evidence of the effectiveness of using artificial intelligence algorithms in enhancing the operational efficiency of energy conversion systems.

The study investigated the thermal performance of a photovoltaic thermal (PVT) collector with a twisted absorber tube and nanoparticle-enhanced phase change material (nano-PCM). The PVT collector consisted of twisted absorber tubes, a container filled with nano-PCM, and a photovoltaic (PV) panel. To assess its efficiency, five different configurations were tested using an indoor solar simulator. The configurations analyzed were as follows: (a) an unenhanced PV panel, (b) PVT with circular absorber tubes (C-PVT), (c) PVT with twisted absorber tubes (T-PVT), (d) C-PVT with nano-PCM (C-PVT-PCM), and (e) T-PVT with nano-PCM (T-PVT-PCM). The thermal, photovoltaic, and combined photovoltaic-thermal efficiencies were evaluated at varying mass flow rates (0.008-0.04kg/s) and a constant solar irradiance of 800W/m2. Among the configurations tested, the T-PVT-PCM configuration demonstrated the highest performance. Specifically, at a mass flow rate of 0.04kg/s, solar irradiance of 800W/m2, and an ambient temperature of 27°C, it achieved photovoltaic, thermal, and combined photovoltaic-thermal efficiencies of 9.46%, 79.40%, and 88.86%, respectively. The utilization of twisted absorber tubes in the design notably improved thermal efficiency by enhancing heat transmission between the liquid and the tube surface. Furthermore, the implementation of T-PVT-PCM led to a significant reduction in surface temperature. Compared to the unenhanced PV panel, it lowered the surface temperature by approximately 30°C, and when compared to C-PVT-PCM, it reduced it by around 10°C. Notably, T-PVT-PCM outperformed the unenhanced PV panel by exhibiting a 34.5% higher photovoltaic efficiency. Overall, the study highlights the performance of the PVT collector with twisted absorber tubes and nanoparticle-enhanced phase change material. The innovative design achieved remarkable thermal efficiency, reduced surface temperatures, and significantly enhanced photovoltaic efficiency compared to traditional configurations. These findings contribute to the development of more efficient and versatile solar energy systems with the potential for broader applications in renewable energy technology.

Control of the amount of solar energy successfully absorbed by photovoltaic system equipment that can follow the movement of sunlight vertically and horizontally at any time is a very urgent need. The method used in this research activity is the utilization of the ESP8266 microcontroller as the primary control of photovoltaic movements that can follow the direction of sunlight based on information from the Light Dependent Resistor (LDR) sensor. The data variables measured and stored include current, voltage, and temperature, which are then processed and transmitted by the ESP 8266 microcontroller to the user through the Internet of Things (IoT) media to the BLINK application. The experimental results show that the proposed system using the ESP8266 microcontroller and LDR sensor increases efficiency, accuracy, speed, and convenience in the monitoring and control system of sunlight intensity by an average of 65%, compared with the manual monitoring system.

A new hybrid system, known as photovoltaic–thermal–thermoelectric (PVT-TE), has been proposed to enhance the conversion efficiency of PV cells by incorporating an intelligent thermal management system, which leverages the dual functions of thermoelectric (TE). This study aims to explore the potential for creating a hybrid system that is more efficient and offers improved performance than standalone photovoltaic thermal (PVT) systems. The key parameters for the creation of a hybrid system were analysed, and the theoretical and experimental results were compared to validate the model. The performance of the PVT-TE collector was evaluated through a steady-state analysis using a one dimensional (1D) mathematical model. Energy balance equations were solved using Microsoft Excel and inverse matrix method. Experiments on PVT and PVT-TE collectors were examined at a solar radiation intensity of 593.16 W/m2. The air mass flow rate was set at 0.009, 0.021, 0.039, 0.069 and 0.095 kg/s for specific radiation intensity. The thermal and electrical performance of the hybrid system was higher than that of the conventional PVT system. The PVT-TE system combines photovoltaic and thermoelectric components, including a thermoelectric module and an air collector. The integration improves system efficiency and performance, surpassing previous research efforts. The PVT-TE system with an air collector has innovative features including efficient thermal-electric conversion, integrated component utilisation, and air collector integration. The overall efficiency of the hybrid system was 7.05%–31.13% higher than the theoretical values and 9.64%–34.83% higher than the experimental values. The increase in the output power of the hybrid system was also higher by 32.59%–55.93%. The findings indicate that the integration thermoelectric (TE) with PV cells has the potential to enhance solar thermal systems' performance. This study provides the basis for further analysis and optimisation of PVT-TE hybrid systems.

Photovoltaic thermal (PVT) collectors convert solar energy into thermal and photovoltaic energy. The thermal performance of a PVT collector with a twisted absorber tube and nanoparticle-enhanced phase change material (Nano-PCM) was evaluated. The experiments were aimed to evaluate the photovoltaic, thermal and combination photovoltaic thermal efficiencies using an indoor solar simulator. Circular and twisted absorber tubes with Nano-PCM were evaluated in two designs. The working fluid was water with 0%, 0.3%, and 0.6% volume fractions of SiC nanofluids. The highest photovoltaic, thermal, and combined photovoltaic thermal efficiencies for the PVT-PCM with twisted tube and 0.6% nanofluids were 9.57, 84.74, and 94.31, respectively. The use of twisted absorber tubes with Nano-PCM increased the efficiency of the PVT collector.

The primary limitation of photovoltaic thermal (PVT) technologies is the adverse effect of solar irradiance-induced heat absorption. In order to enhance the efficiency of the system, it is essential to incorporate a cooling mechanism. The utilization of a reversed circular flow jet impingement (RCFJI) was implemented as a cooling mechanism for a bifacial PVT solar collector. This study aims to analyze the exergy efficiency of a RCFJI bifacial PVT solar collector. An indoor experiment was conducted using a solar simulator with a solar irradiance of 500–900W/m2 and a mass flow rate of 0.01–0.14 kg/s. The findings revealed that the highest photovoltaic exergy attained was 47.2W under solar irradiance of 900W/m2 and a mass flow rate of 0.14 kg/s. Meanwhile, the highest thermal exergy attained was 9.67W under 900W/m2 solar irradiance and 0.14 kg/s mass flow rate. Overall, the exergy efficiency attained a maximum value of 12.64% under 900W/m2, while the lowest exergy efficiency observed was 12.25% under 500W/m2. In addition, the optimal operational mass flow determined was 0.06 kg/s. The findings indicate that the optimal performance of the RCFJI bifacial PVT solar collector is achieved through higher exergy efficiency, which signifies a reduced requirement for input energy. Consequently, more energy can be harnessed.

Transformation of salty seawater into fresh water by the aid of solar energy is one of the solutions for overcoming the lack of these waters with an eco-friendly procedure. The use of solar stills is one of the solutions that use solar energy with a simple design to produce fresh water in small to moderate amounts. Hemispherical solar stills are one kind of still design that does not require a particle rotational orientation, and they have proved to be more efficient than traditional designs. Solar stills generally possess a low thermal efficiency, with limitations of working hours, i.e., only daytime. To overcome these problems, rocks placed in the saline water basin are used as heat storage materials to increase the working period of the design. In the present work, different amounts of river rocks are utilized to study the effect of this addition experimentally. Steady state tests are conducted to study the influence of these additive rocks on the enhancement of solar energy absorption, since increased working time is assured by published research. Two volumes of rocks (300 mL and 600 mL) were tested, and both increased water productivity, by 52% and 58%, respectively. The increases are explained by the increases in solar energy absorption, since steady state cases were used.

Solar irradiation data is essential for the feasibility of solar energy projects. Notably, the intermittent nature of solar irradiation influences solar energy use in all forms, whether energy or agriculture. Accurate solar irradiation prediction is the only solution to effectively use solar energy in different forms. The estimation of solar irradiation is the most critical factor for site selection and sizing of solar energy projects and for selecting a suitable crop selection for the area. But the physical measurement of solar irradiation, due to the cost and technology involved, is not possible for all locations across the globe. Numerous techniques have been implemented to predict solar irradiation for this purpose. The two types of approaches that are most frequently employed are empirical techniques and artificial intelligence (AI). Both approaches have demonstrated good accuracy in various places of the world. To find out the best method, a thorough review of research articles discussing solar irradiation prediction has been done to compare different methods for solar irradiation prediction. In this paper, articles predicting solar irradiation using AI and empirical published from 2017 to 2022 have been reviewed, and both methods have been compared. The review showed that AI methods are more accurate than empirical methods. In empirical models, modified sunshine-based models (MSSM) have the highest accuracy, followed by sunshine-based (SSM) and non-sunshine-based models (NSM). The NSM has a little lower accuracy than MSSM and SSM, but the NSM can give good results in sunshine data unavailability. Also, the literature review confirmed that simple empirical models could predict accurately, and increasing the empirical model's polynomial order cannot improve results. Artificial neural networks (ANN) and Hybrid models have the highest accuracy among AI methods, followed by support vector machine (SVM) and adaptive neuro-fuzzy inference system (ANFIS). The increase in efficiency by hybrid models is minimal, but the complexity of models requires very sophisticated programming knowledge. ANN's most important input factors are maximum and minimum temperatures, temperature differential, relative humidity, clearness index and precipitation.

The influence of the Nd:YAG laser's oscillation energy on creating textured surfaces on silicon wafers is investigated in this study. The silicon wafer surfaces were directly ablated by a pulsed Nd:YAG laser beam to create the texturing, which was then examined using UV–Vis spectroscopy, AFM and FESEM to determine its characteristics. The reflectance was reduced up to 15% after laser texturing of multicrystalline silicon wafers. The silicon surface suffers from structural defects and a laser damage layer as a result of the laser texturing process, which in turn has an effect on the lifespan of the photo-generated carriers. To compensate for the laser damage layer, the silicon surface was cleaned with diluted KOH (15%) to remove undesirable particles and the oxide layer. Surface roughness and reflectance in silicon solar cells were changed depending on the laser oscillation energy utilized for texturing. The roughness and reflectance were measured using AFM and UV–Vis, respectively. The laser oscillation energy of 84 J/p had the highest average roughness of 0.2104 m and the lowest reflectance of 5%. As a result, standard silicon solar cell devices revealed photovoltaic conversion efficiencies of roughly 7.5% and 5.0% for laser-textured grid and one-dimensional line patterns, respectively.

A hybrid PVT (photovoltaic thermal system) nanofluid circulation system was tested, which included a micro-fin tube (inner grooved) and twisted tape with nano PCM (phase change material). The use of nanoparticles allowed the nano PCM and nanofluid to have higher thermal conductivities, improving their performance. Experiments were carried out within a controlled environment by utilizing an indoor solar simulator with a solar irradiance level of 800W/m2. The PVT system used water/SiC (0.6, 0.3) vol% nanofluid as a working fluid. The nanoPCM comprises 1% SiC nanoparticles, which enhance thermal, electrical (photovoltaic), and photovoltaic thermal efficiency (total efficiency). The mass flow rate range is 0.008–0.058 kg/s. The energy analysis showed that the PVT had an electrical efficiency of 10.8%. The system's maximum thermal efficacy was 83.3% for the PVT with the T (twisted tape), MF (micro-fins), NF (nanofluids), and NPCM (Nano PCM). The percentage of improved electrical power compared between the bare PV and the PVT NF T NF NPCM was 44.5%. The micro fin tube with twisted tape improved the heat transfer properties for enhanced thermal performance.

The insertion of a highly resistive transparent (HRT) layer with the ability to transfer an optimum portion of the UV range of sunlight is targeted in this study by bandgap engineering through varying the thickness as well as the concentration of dopants. The integrability of ZnO and Mg-doped ZnO (MZO) as the potential HRT layers for CdTe solar cell devices with the possibility of bandgap management, high transmission at short wavelength and reduced current loss by inhibiting holes from reaching interfacial defects is proposed. Using SCAPS-1D modelling software, key performance parameters such as open circuit voltage (Voc), short circuit current (Jsc), fill factor (FF), conversion efficiency (η), and quantum efficiency (QE) were evaluated for the proposed devices by varying the carrier concentration and series resistance (Rs). The simulation was carried out based on experimental data such as thickness, optical characteristics and bandgap to validate the findings. Results showed that the conversion efficiency for thin-film solar cells of ITO/CdS/CdTe, ITO/ZnO/CdS/CdTe and ITO/MZO/CdS/CdTe were attained to be 17.83%, 18.76% and 20.27%, respectively. The optimal carrier concentration using ZnO, and MZO was found to be 1016 cm−3 for an efficient CdTe solar cells design.

The performance of photovoltaic thermal (PV/T) type solar collectors can be optimised with the use of bifacial photovoltaic panel since it can utilise the absorbed incident solar irradiance from its front and rear surface. However, its potential is highly determined by the amount of the reflected solar irradiance onto the rear surface of the panel. In this research, we assessed the potential of a novel double pass photovoltaic/thermal (PV/T) solar air collector using semi-transparent bifacial PV panel with compound parabolic concentrator and mirror reflector in Malaysia. The use of CPC and reflector was introduced to increase the amount of reflected light and hence increasing the efficiency of the collector. A mathematical model was developed, and validated o predict the performance of the solar collector. Using the validated mathematical model, the optimum mass flow rate of the bifacial PV/T collector with CPC and mirror reflector was found at 0.0589 kg/s. At this flow rate, when operated under the hot climate of Malaysia, the temperature output of as high as 51 °C is achievable implying its potential as a preheated air to regenerate desiccant materials in solar assisted cooling system and for agriculture drying application. Also, when compared with the bifacial PV/T solar collector without the CPC, the total energy useful was found almost 40% higher.

Global solar radiation can theoretically be approximated in terms of tilt and azimuth of the surface regarding the impossibility of simultaneous measurement of solar radiation at various surface tilt and azimuth angles. Moreover, the random and anisotropic nature of diffuse radiation in a tropical climate makes it extremely difficult to estimate global solar radiation accurately as a function of surface tilt and azimuth angles. This study aims to develop a novel experimental and theoretical approach in the form of a computational network in order to determine a precise combined model integrated with global horizontal solar radiation to evaluate global tilted solar radiation in a tropical climate. Obtained results revealed that precisely estimation of the global tilted solar radiation was possible, by combining geometric factors for the tilted beam solar radiation, a combination of Gueymard and Louche models for the tilted diffuse solar radiation, and isotropic ground reflectance model for the ground reflected radiation, along with global horizontal solar radiation. It was observed that the accuracy of the model developed was higher for the partly sunny sky compared to the cloudy and rainy sky, estimates were more accurate on south-facing surfaces, and the model's accuracy declined with the increasing tilt angle of the surface. The statistical analysis exhibited excellent agreement between the measured data and simulation results, considering the value of normalized mean absolute error (nMAE %), normalized root mean squared error (nRMSE %), and mean absolute percentage error (MAPE %), which were in the ranges 0.22–0.94, 0.27–1.11, and 0.23–1.02, respectively for estimating global tilted solar radiation in various regions of Peninsular Malaysia, and they were respectively found in the range of 10.2–27.5%, 16.1–38.9%, and 6.0–17.8%, for evaluating the monthly optimum tilt angle towards the south, that leads to a loss of solar energy from 1.3 to 5.4 kWh/m2/year in Peninsular Malaysia. This search revealed that the experimental and theoretical approach employed in this study can be extended to more climatic regions.

This research examines the feasibility of employing bifacial photovoltaic (bPV) panels on PVT solar collectors to improve electrical efficiency. Bifacial PVT (bPVT) collector with a V-groove mirror reflector is developed in this paper. The mathematical model is developed based on energy balance equations by using the inverse matrix method. The experimental findings are compared with the theoretical results to verify the mathematical model. The experiments on a bPVT collector are conducted at different mass flow rates and solar radiation intensities in the range of 0.032–0.092 kgs−1 and 508–820 Wm−2, respectively. The findings show that the temperature differential and bPV panel temperature decrease as the mass flow rate increases. Consequently, this adds to the increased electric and thermal energy of a bPVT collector. The theoretical findings report an overall performance of 58.2% at mass flow rate of 0.092 kgs−1 and solar radiation of 820 Wm−2. According to the experimental analysis, the highest energy efficiency obtained is 59.24% at the same parameter. In conclusion, this research contributes to the development of PVT collector system technology where the theoretical and experimental studies have proven the feasibility to integrate the bifacial PV and reflector on PVT solar collectors.

Residential photovoltaic systems are a cost-effective solution for Palestinians to reduce their power costs while improving the environment. Despite their numerous advantages, these systems have several negative effects on the entire electric grid infrastructure. Increased penetration of photovoltaic (PV) systems, for example, may result in a fall in the power factor of the distribution grid. When the power factor is low, heat production and switch failures are more likely to occur. Even though comparable research has been published in the past, this is the first time PV systems have been investigated in terms of power factors in Palestine. This research serves as a resource for people interested in how photovoltaics (PVs) impact their systems' total power factor. To begin, the researchers in this study presented an intuitive power factor selection criterion for photovoltaic (PV) systems. Second, the article included a proposal for an auxiliary power factor controller. This article's conclusions may be utilized by municipalities, grid operators, and legislators to aid them in planning, forecasting, and accommodating new PV systems in their grids in terms of total power factor, as demonstrated by the results of this study. However, even though the data in this study is drawn from Palestinian sources, it may be applied to other regions because the data sets used are worldwide in scope.

This article deals with the impact of including transverse ribs within the absorber tube of the concentrated linear Fresnel collector (CLFRC) system with a secondary compound parabolic collector (CPC) on thermal and flow performance coefficients. The enhancement rates of heat transfer due to varying governing parameters were compared and analyzed parametrically at Reynolds numbers in the range 5,000–13,000, employing water as the heat transfer fluid. Simulations were performed to solve the governing equations using the finite volume method (FVM) under various boundary conditions. For all Reynolds numbers, the average Nusselt number in the circular tube in the CLFRC system with ribs was found to be larger than that of the plain absorber tube. Also, the inclusion of transverse ribs inside the absorber tube increases the average Nusselt number by approximately 115% at Re = 5,000 and 175% at Re = 13,000. For all Reynolds numbers, the skin friction coefficient of the circular tube with ribs in the CLFRC system is larger than that of the plain absorber tube. The coefficient of surface friction reduces as the Reynolds number increases. The performance assessment criterion was found to vary between 1.8 and 1.9 as the Reynolds number increases.

The efficiency of the photovoltaic cell ultimately decreases as its temperature rises. A hybrid PVT (photovoltaic thermal system) is one of the innovative techniques employed to increase that efficiency. This study utilized a cooling nanofluid circulation system with a micro fin tube (inner grooved) encapsulated with nano PCM (Phase Change Material). The utilization of nanoparticles allowed nano PCM and Nanofluid to have higher thermal conductivities increasing efficiencies. Experiments were conducted in a controlled environment using an indoor solar simulator. Water and nanofluid with 0.6 vol% SiC were used as working fluids in the PVT system. The nano PCM contains 1% SiC nanoparticles, which improves electrical (photovoltaic), thermal, and photovoltaic thermal efficiencies (total efficiencies). The mass flow rate ranges from (0.008–0.058 kg/s. The energy analysis indicated that the PVT had an electrical efficiency of 9.6%. The system’s highest thermal efficiency was 77.5% for the PVT M.F.N.F.N.PCM where the M.F (micro-fins), N.F (nanofluids), and N.PCM (nanoPCM).

Poly(3,4-ethylenedioxythiophene)/manganese oxide coated on porous carbon nanofibers (P-CNFs/PEDOT/MnO2) is developed as an advanced anode material via the innovative combination of multiple routes, such as electrospinning, carbonization and electrodeposition. The structural and morphological characterization of the P-CNFs/PEDOT/MnO2 electrode indicates that crosslinked and rough surface provides, as a strategic point, enough active sites for Li+storage. PEDOT nanoparticles and irregular block shape of MnO2 are randomly oriented on the P-CNFs surface, thus allowing a possible electron-conducting pathway, increment in catalytic activity as well as a buffer of the volumetric changes upon cycling. Consequently, the obtained P-CNFs/PEDOT/MnO2 electrode exhibits a truly promising electrochemical performance, which displays discharge capacity of 1477 mAh/g, better than that of P-CNFs/PEDOT (1191 mAh/g), P-CNFs/MnO2 (763 mAh/g) and P-CNFs (433 mAh/g), at a current density of 2 mA/g. In addition, satisfactory electrochemical performances of the as-prepared P-CNFs/PEDOT/MnO2 electrode after 20 cycles of charge/discharge are detected, with a Coulombic efficiency higher than 90% and a charge-transfer resistance being relatively smaller (131.91 Ω) than that of P-CNFs/PEDOT (232.66 Ω) and P-CNFs/MnO2(169.17 Ω) electrodes. Thus, these results indicate that the P-CNFs/PEDOT/MnO2 electrode could offer a great potential to replace commercial graphite for lithium-ion batteries.

Solar energy is an accessible and sustainable energy source to meet the rising air conditioning demand. This study investigated the performance of solar thermal assisted sorption cooling systems, namely, solar absorption (SABC) and adsorption cooling (SADC) systems. A novel analytical approach to determine the techno-economic potential for specific climate conditions has been developed. The climatic conditions of Malaysia were used as a case study. Both cooling systems were simulated using TRNSYS coupled with VISUAL BASIC and optimized using a multi-objective optimization algorithm implemented in MATLAB. The results show that the COPchiller and collector area have the most significant impact on the performance and primary energy consumption of SABC and SADC systems. On average, 36 % and 27 % of the useful energy gain of solar collectors was converted to the cooling effect in SABC and SADC systems, respectively. Meanwhile, the minimum amount of non-renewable primary energy, the non-renewable primary energy savings ratio, and the least payback period are 0.57 and 0.39, 7.6 % and 7.5 %, and 4 and 9 years, for the SABC and SADC systems, respectively.

The impact of utilizing Nanofluids with different metal oxide nanoparticles on heat transfer enhancement and fluid flow for concentration photovoltaic thermal the CPVT collector with Fresnel lens is demonstrated using CFD simulation. With the rising temperature, the electrical efficiency and output power of Multi-Junction Solar Cells drop. Four different types of nanofluids and water are utilized as cooling fluids to disperse heat from Multi-Junction Solar Cells by moving the fluid within the mini-channel beneath the PV Solar Cells. In the current analysis, the Reynolds numbers range from 2000 to 18000. For all forms of cooling fluids, the average Nusselt numbers are augmented by rising Reynolds numbers. The CFD results demonstrated that the Nusselt number of all nanofluid cooling fluids is greater than that of water. When compared to water in a CPVT collector, water-SiO2 nanofluid provides the maximum heat transfer improvement of 12.5%. The silicon dioxide nanoparticles have high thermal conductivity, with the water-SiO2 nanofluid exhibiting the greatest heat transfer increase, followed by water-Al2O3, water-ZnO, water-CuO, and water. The average top surface temperature of the mini-channel for the CPVT collector is reduced by 7% when water-SiO2 nanofluid is used as a cooling fluid and by 3.4% when water is used. The usage of water-SiO2 nanofluid has a significant impact on the heat dissipation with high heat transfer enhancement from Multi-Junction Solar Cells in CPVT collector, leading to an increase in electrical efficiency.

When it comes to guaranteeing appropriate performance for buildings in terms of energy efficiency, the building envelope is a crucial component that must be presented. When a substance goes through a phase transition and either gives out or absorbs an amount of energy to provide useful heat or cooling, it is called a phase-change material, or PCM for short. Transitions often take place between the matter’s solid and liquid states. Buildings use PCMs for a variety of purposes, including thermal comfort, energy conservation, managing the temperature of building materials, reducing cooling/heating loads, efficiency, and thermal load shifting. Improved solutions are applied using new method and approach investigations. Undoubtedly, researching and applying PCM use in building applications can help create buildings that are more energy-efficient and environmentally friendly, while also increasing thermal comfort and consuming less energy. It provides a possible answer to the problems posed by climate change, rising energy demand in the built environment, and energy use optimisation. However, it is true that no particular research has yet been conducted to thoroughly analyse the linked PCM applications in the building industry. Thus, the principal tactics are addressed in this paper to determine current and efficient methods for employing PCMs in buildings to store thermal energy. By gathering around 50 instances from the open literature, this study conducts a thorough assessment of the up-to-date studies between 2016 and 2023 that used PCMs as thermal energy storage in building applications. As a result, this review aims to critically evaluate the PCM integration in buildings for thermal energy storage, identify a number of issues that require more research, and draw some important conclusions from the body of literature. Specifically, the building envelope roof and external wall uses of PCMs are highlighted in this research. Applications, general and desired characteristics, and PCM types and their thermal behaviour are described. In comparison to a traditional heat storage tank that simply contains water, this review indicates that a water storage tank containing 15% PCM improves heat storage by 70%. Also, less than 7 °C of internal air temperature was reduced by the PCMs in the walls, which avoided summer warming. Finally, using PCM for space cooling resulted in substantial energy savings across the various seasons.

Airborne dust and dust storms are natural disasters that transport dust over long distances from the source basin, sometimes reaching hundreds of kilometers. Today, Iraq is a basin that produces dust storms that strike all neighboring countries such as Iran, Kuwait and Saudi Arabia. These storms affect the productivity and capacity of the photovoltaic modules and reduce the amount of electricity that is generated clearly. Airborne dust reduces the intensity of solar radiation by scattering and absorbing it. In addition, the dust accumulated on the photovoltaic modules causes a deterioration in their productivity. In this study, an extensive review of wind movement and its sources, especially those that hit the city of Baghdad, the capital of Iraq, was conducted. Practical experiments were also carried out during a storm to measure important variables that had not been measured practically before at this site. The experimental tests were carried out starting from 1 April 2022 and continued until 12 April. Within this period, a dust storm occurred that lasted for three consecutive days that was considered one of the most severe storms that the city of Baghdad had experienced in the last few years. Practical measurements showed a deterioration in the solar radiation intensity by up to 54.5% compared to previous days. The air temperature during the storm decreased by 21.09% compared to the days before the storm. From the measurements of ultrafine aerosol particles PM1 and PM2.5, there was a significant increase of 569.9% and 441% compared to the days before the storm, respectively. Additionally, the measurements showed an increase of 217.22% and 319.21% in PM10 and total suspended particles, respectively. Indoor performance experiments showed a deterioration of current, voltage, power and electrical efficiency by 32.28%, 14.45%, 38.52% and 65.58%, respectively, due to dust accumulated during the storm days compared to the previous days. In the outdoor experiments, the rates of deterioration of current, voltage, power and electrical efficiency were greater, reaching 60.24%, 30.7%, 62.3% and 82.93%, respectively, during the storm days compared to the days before it. During a storm, cleaning the panels is futile due to the high concentration of dust in the air, especially by water. However, the photovoltaic modules can be dry cleaned with bristle brushes after the storm has subsided.

In this study, different chemically treated coconut coir (CC), local waste biomass, has been developed as an adsorbent for the removal of methylene blue (MB) from an aqueous solution. The acid and base treated coconut coir with higher water and moisture absorbency have been investigated for dye removal performance. The influence of different experimental factors such as initial MB concentration and condition of chemical treatments on dye removal performance of coconut coir were studied. The compositional and structural changes of the treated samples were determined using X-ray diffraction (XRD), scanning electron microscope (SEM), X-Ray photoelectron spectroscopy (XPS), Fourier Transform Infrared spectroscopy (FT-IR), and Thermogravimetric analysis (TGA). The best sample showed the removal percentage of methylene blue equal to % 92.36 and %91.62 in 0.05mM and 0.03 mM of MB, respectively. The results showed the simply modified cheap waste biomass could be used as an effective green adsorbent for dye removal in aqueous solution.

Solar energy is a renewable energy that can produce heat via a thermal system and generate electricity via a photovoltaic (PV) module. A photovoltaic-thermal (PVT) collector is a system that has a PV module combined with a thermal collector system. The PVT collector is a popular technology for harvesting solar energy. A PVT collector can generate both electrical and thermal energies simultaneously. The study aims to validate the PV and outlet temperature for various mass flow rates and solar radiation. To develop a predictive model, a steady-state energy analysis of a PVT air collector was performed. An energy balance equation was solved using the matrix inversion method. The theoretical model was developed and validated against the experimental results, which have a similar trend and are consistent with the experimental results. On the other hand, the validated model was used to study the performances of PVT air collectors using exergy analysis for the mass flow rate ranging from 0.007 kg/s to 0.07 kg/s and solar radiation ranging from 385 W/m2 to 820 W/m2. The result from the mathematical model was found to be consistent with the experimental data with an accuracy of about 95 %. The average PVT exergy efficiency was found to be 12.7 % and 12.0 % for the theoretical and experimental studies, respectively.

Abstract The establishment of perovskite solar cells (PSCs) in terms of their power-conversion efficiency (PCE) over silicon-based solar cells is undeniable. The state-of-art of easy device fabrications of PSCs has enabled them to rapidly gain a place in third-generation photovoltaic technology. Numerous obstacles remain to be addressed in device efficiency and stability. Low performance owing to easily degraded surface and deterioration of perovskite film quality resulting from humidity are issues that often arise. This work explored a new approach to producing high-quality perovskite films prepared under high relative humidity (RH = 40%–50%). In particular, the ubiquitous 4-tert-butylpyridine (tBp) was introduced into lead iodide (PbI2) precursor as an additive, and the films were fabricated using a two-step deposition method followed by a delay-deposition technique of methylammonium iodide (MAI). High crystallinity and controlled nucleation of MAI were needed, and this approach revealed the significance of time control to ensure high-quality films with large grain size, high crystallography, wide coverage on substrate, and precise and evenly coupled MAI molecules to PbI2 films. Compared with the two-step method without time delay, a noticeable improvement in PCE from 3.2 to 8.3% was achieved for the sample prepared with 15 s time delay. This finding was primarily due to the significant enhancement in the open-circuit voltage, short-circuit current, and fill factor of the device. This strategy can effectively improve the morphology and crystallinity of perovskite films, as well as reduce the recombination of photogenerated carriers and increase of current density of devices, thereby achieving improved photovoltaic performance.

Fabrication of quasi-solid state polymer electrolytes are recently being endorsed by electrochemists due to its superior electrical and physical properties. With the aspiration to develop a sustainable electrolyte component, this study is a novel attempt to fabricate quasi-solid electrolyte based on esterified starch. Potato starch was chemically modified via simple phthaloylation method. The resulting amorphous, hydrophobic starch derivative was used as a polymer base to prepare cost effective thermoplastic gel electrolytes via incorporation of propylene carbonate, dimethylformamide and lithium iodide. Fourier transform infrared spectroscopy and X-ray diffraction characterizations verified the impact of phthaloylation and plasticization in suppressing the crystallinity and hydrophilicity of starch. The biopolymer gel with 40 wt.% LiI recorded the highest room temperature ionic conductivity of 4.82 mS cm−1. The sample with highest ionic conductivity recorded the best efficiency of 3.56%, which is one of the highest values for starch electrolyte-based dye-sensitized solar cells (DSSC). The optimized efficiency indicate that starch-based electrolyte has good prospects for fabrication of quasi-solid DSSC.

Symmetrical compound parabolic concentrators (CPC) for a stationary double pass photovoltaic thermal (PV/T) air solar collector has been widely employed. However, for high yearly energy delivery, the solar incidence angle must be within the full acceptance angle of the CPC which is a challenge to determine for a symmetrical CPC. This paper presents the performance enhancement of a double pass photovoltaic/thermal air solar collector using an asymmetric compound parabolic concentrator (PV/T-ACPC) suitable for building façade application. Mathematical modelling was developed and validated against established experimental results. The potential of double pass PV/T-ACPC was then evaluated for different locations that represent low, mid, and high latitudes. Double pass PV/T-ACPC outperforms the conventional symmetric compound parabolic concentrator (PV/T-CPC) and the conventional flat type of double pass PV/T solar air collector. When compared with conventional flat type, the average percentage increase in the average daily total power yield for the PV/T-ACPC is as high as 14% and 50% for the low and mid-latitude, and high latitude countries, respectively. Meanwhile, for the PV/T CPC, the percentage of the average daily total power yield was slightly negative in value for low and mid-latitude countries, which indicates worse performance compared to the conventional type.

Energy systems are dynamic and transitional because of alternative energy resources, technological innovations, demand, costs, and environmental consequences. The fossil fuels are the sources of traditional energy generation but has been gradually transitioned to the current innovative technologies with an emphasis on renewable resources like solar, and wind. Despite consistent increases in energy prices, the customers’ demands are escalating rapidly due to an increase in populations, economic development, per capita consumption, supply at remote places, and in static forms for machines and portable devices. The energy storage may allow flexible generation and delivery of stable electricity for meeting demands of customers. The requirements for energy storage will become triple of the present values by 2030 for which very special devices and systems are required. The objective of the current review research is to compare and evaluate the devices and systems presently in use and anticipated for the future. The economic and environmental issues as well as challenges and limitations have been elaborated through deep and strong consultation of literature, previous research, reports and journal. The technologies like flow batteries, super capacitors, SMES (Superconducting magnetic energy storage), FES (Flywheel Energy Storage), PHS (Pumped hydro storage), TES (Thermal Energy Storage), CAES (Compressed Air Energy Storage), and HES (Hybrid energy storage) have been discussed. This article may contribute to guide the decision-makers and the practitioners if they want to select the most recent and innovative devices and systems of energy storage for their grids and other associated uses like machines and portable devices. The characteristics, advantages, limitations, costs, and environmental considerations have been compared with the help of tables and demonstrations to ease their final decision and managing the emerging issues. Thus, the outcomes of this review study may prove highly useful for various stakeholders of the energy sector.

Solar adsorption air conditioning system (SADCS) is an excellent alternative to the conventional vapour compression system (VCS). SADCS has advantages over VCS system notably that it is a green cooling technology that utilizes solar energy to drive the adsorption/desorption cycle, using pure water as a green HFC-free refrigerant, mechanically simple and can be operated without moving parts other than the magnetic valves. In the last decade, several developments and innovations have been achieved in the field of SADCS research. However, further research is needed to bring this technology to practical level. Hence, this paper first discusses the literature survey that adds insights into the research of SADCS technologies with emphasis placed on the practical research that has been conducted at lab-scale and commercial level. Then, the potential of SADCS for cooling applications of an office building in tropical climate is discussed using simulation in TRNSYS. From the simulation we found that the solar fraction of the SADCS system is as high as 63 %, with the temperature and the relative humidity of an office space can reach an average of 20 °C and 60 % respectively, which are within the range of the thermal comfort level for the occupants.

Photovoltaic/thermal (PV/T) systems used to produce electricity and heat concurrently. The production and efficiencies of these systems were specified by the materials, design, and weather data of the location. In this study, a 100-Watt Web-configuration PV/T systems designed, tested, and evaluated in Sohar, Oman. Two identical Web configuration PV/T systems designed, installed, and compared with a conventional PV system. A water-based and a Silicon Carbide SiC nanofluid used in the PV/T systems tested to evaluate the enhancement of the PV/T production in term of electrical and thermal parameters. It is found that the PV electrical power increase from 55.2 W, to 63.16 W and 72.28 W for water-based and nanofluid based PV/T, respectively. Also, the temperature cell reduced (3.92% and 15.26%), electrical efficiency increased (8.51% and 20.21%), and thermal efficiency increased (29.0% and 43.3%) for water-based and nanofluid based PV/T, respectively. Based on the evaluation of the numerical and experimental results, it is concluded that the nanofluid enhances electrical and thermal behaviours and suitable for Oman weather.

Tungsten oxide (WOx) thin films were synthesized through the RF magnetron sputtering method by varying the sputtering power from 30 W to 80 W. Different investigations have been conducted to evaluate the variation in different morphological, optical, and dielectric properties with the sputtering power and prove the possibility of using WOx in optoelectronic applications. An Energy Dispersive X-ray (EDX), stylus profilometer, and atomic force microscope (AFM) have been used to investigate the dependency of morphological properties on sputtering power. Transmittance, absorbance, and reflectance of the films, investigated by Ultraviolet-Visible (UV-Vis) spectroscopy, have allowed for further determination of some necessary parameters, such as absorption coefficient, penetration depth, optical band energy gap, refractive index, extinction coefficient, dielectric parameters, a few types of loss parameters, etc. Variations in these parameters with the incident light spectrum have been closely analyzed. Some important parameters such as transmittance (above 80%), optical band energy gap (~3.7 eV), and refractive index (~2) ensure that as-grown WOx films can be used in some optoelectronic applications, mainly in photovoltaic research. Furthermore, strong dependencies of all evaluated parameters on the sputtering power were found, which are to be of great use for developing the films with the required properties.

The silicon heterojunction solar cell (SHJ) is considered the dominant state-of-the-art silicon solar cell technology due to its excellent passivation quality and high efficiency. However, SHJ’s light management performance is limited by its narrow optical absorption in long-wave near-infrared (NIR) due to the front, and back tin-doped indium oxide (ITO) layer’s free carrier absorption and reflection losses. Despite the light-trapping efficiency (LTE) schemes adopted by SHJ in terms of back surface texturing, the previous investigations highlighted the ITO layer as a reason for an essential long-wavelength light loss mechanism in SHJ solar cells. In this study, we propose the use of Molybdenum disulfide (MoS2) as a way of improving back-reflection in SHJ. The text presents simulations of the optical response in the backside of the SHJ applying the Monte-Carlo raytracing method with a web-based Sunsolve high-precision raytracing tool. The solar cells’ electrical parameters were also resolved using the standard electrical equivalent circuit model provided by Sunsolve. The proposed structure geometry slightly improved the SHJ cell optical current density by ~0.37% (rel.), and hence efficiency (η) by about 0.4% (rel.). The SHJ cell efficiency improved by 21.68% after applying thinner back ITO of about 30 nm overlayed on ~1 nm MoS2. The efficiency improvement following the application of MoS2 is tentatively attributed to the increased NIR absorption in the silicon bulk due to the light constructive interface with the backside components, namely silver (Ag) and ITO. Study outcomes showed that improved SHJ efficiency could be further optimized by addressing front cell components, mainly front ITO and MoS2 contact engineering.

Both electrical and thermal efficiencies combine in determining and evaluating the performance of a PV/T collector. In this study, two PV/T systems consisting of poly and monocrystalline PV panels were used, which are connected from the bottom by a heat exchanger consisting of a spiral tube through which a nanofluid circulates. In this study, a base fluid, water, and ethylene glycol were used, and iron oxide nanoparticles (nano-Fe2O3) were used as an additive. The mixing was carried out according to the highest specifications adopted by the researchers, and the thermophysical properties of the fluid were carefully examined. The prepared nanofluid properties showed a limited effect of the nanoparticles on the density and viscosity of the resulting fluid. As for the thermal conductivity, it increased by increasing the mass fraction added to reach 140% for the case of adding 2% of nano-Fe2O3. The results of the zeta voltage test showed that the supplied suspensions had high stability. When a mass fraction of 0.5% nano-Fe2O3 was added the zeta potential was 68 mV, while for the case of 2%, it reached 49 mV. Performance tests showed a significant increase in the efficiencies with increased mass flow rate. It was found when analyzing the performance of the two systems for nanofluid flow rates from 0.08 to 0.17 kg/s that there are slight differences between the monocrystalline, and polycrystalline systems operating in the spiral type of exchanger. As for the case of using monocrystalline PV the electrical, thermal, and total PV/T efficiencies with 2% added Fe2O3 ranged between 10% to 13.3%, 43–59%, and 59 to 72%, respectively, compared to a standalone PV system. In the case of using polycrystalline PV, the electrical, thermal, and total PV/T efficiencies ranged from 11% to 13.75%, 40.3% to 63%, and 55.5% to 77.65%, respectively, compared to the standalone PV system. It was found that the PV/T electrical exergy was between 45, and 64 W with thermal exergy ranged from 40 to 166 W, and total exergy from 85 to 280 W, in the case of using a monocrystalline panel. In the case of using polycrystalline, the PV/T electrical, thermal, and total exergy were between 45 and 66 W, 42–172 W, and 85–238 W, respectively. The results showed that both types of PV panels can be used in the harsh weather conditions of the city of Baghdad with acceptable, and efficient productivity.

In this study, the heat transfer characteristics of the flat plate collectors with circular and elliptical serpentine tubes are theoretically analyzed and compared in terms of m˙, Re, Nu, hfi, FR, Qu, and μTh under various water flow rates and the standard test conditions. The results reveal that the maximum μTh correspondence to the elliptical serpentine design with 56% under turbulent flow, and the minimum μTh of 47% for the circular cross-section under laminar flow. In addition, it was found that the highest useful energy gain per unit time (493.8 W) through the system is possible when FR, hfi, Nu, and m˙ are maximum and vice versa. It was concluded that, at the same area, the larger contact area in the elliptical cross-section compared to the circular would improve FR and Qu by an average of 2%. Overall, it is crucial to evaluate the thermal parameters of the thermal collector during the preliminary design stage to fabricate a highly efficient system and save time as well as initial cost.

This study presents a prediction model for comparing the performance of six different photovoltaic (PV) modules using artificial neural networks (ANNs), with simple inputs for the model. Cell temperature (Tc), irradiance, fill factor (FF), short circuit current (Isc), open-circuit voltage (Voc), maximum power (Pm), and the product of Voc and Isc are the inputs of the neural networks’ processes. A Prova 1011 solar system analyzer was used to extract the datasets of IV curves for six different PV modules under test conditions. As for the result, the highest FF was the mono-crystalline with an average of 0.737, while the lowest was the CIGS module with an average of 0.66. As for efficiency, the most efficient was the mono-crystalline module with an average of 10.32%, while the least was the thin-film module with an average of 7.65%. It is noted that the thin-film and flexible mono-modules have similar performances. The results from the proposed model give a clear idea about the best and worst performances of the PV modules under test conditions. Comparing the prediction process with the real dataset for the PV modules, the prediction accuracy for the model has a mean absolute percentage error (MAPE) of 0.874%, with an average root mean square error (RMSE) and mean absolute deviation (MAD) of, respectively, 0.0638 A and 0.237 A. The accuracy of the proposed model proved its efficiency for predicting the performance of the six PV modules.

Performance degradation of photovoltaic modules occurs when cell temperature increases; this is due to losses within the cell and the effect of surrounding weather as well. An increase in cell temperature leads to a decrease in the open-circuit voltage and hence, the electrical power produced by the PV. A nanofluid and nano-PCM (paraffin wax) -based PV/T hybrid collector has been employed in this paper. The experiments focus on the electrical performance and characteristics of the PV module under the weather conditions of Bangi-Malaysia. The cooling technique used is attaching the module to a nano-PCM tank and running nanofluids within. The results from the experimental tests show a maximum PV efficiency of 13.7% under operation for PV/T collector as appose to conventional PV module, which achieved an efficiency of 7.1%, which is suitable relative to the efficiency of 14% under standard testing conditions.

Working fluid with higher thermal conductivity and tube with better fluid mixing are two crucial elements for heat transfer enhancement in heat exchanger system. Hence, several methods and techniques have been explored to improve heat transfer efficiency, including dispersing nanoparticles into conventional heat transfer fluid and inserting instruments inside the tube of the heat exchanger. Studies have shown that nanofluid can improve heat transfer efficiency of the system due to its higher thermal conductivity and drastic Brownian motion of nanoparticles while inserts within tube can improve heat transfer efficiency by increasing axial velocity of working fluid for better fluid mixing. This article summarized 109 of journals from recent research on heat transfer enhancement of nanofluid flowing inside the tube with inserts as well as discussing the significant parameters that affected the system’s efficiency such as nanoparticles’ volume fraction, Reynolds number and types and configurations of inserts. Ultimately, analysis will be carried out to determine the most suitable modification of twisted tape inserts with the most optimum value of nanoparticle volume fraction for turbulence flow regime. Finally, some problems that need to be solved for future research such as agglomeration and pressure drop are discussed.

This paper investigates double-pass solar air thermal collectors with lava rock as the porous media. The addition of lava rock serves as short-term sensible thermal storage for a solar drying system. It also enhances the convective heat transfer rate to the airflow due to an increased heat transfer area and increased turbulence in the air channel. A mathematical model was developed based on energy balance equations and was numerically solved in MATLAB. The collector’s thermal performance was studied at various levels of solar intensity and at different wind speeds for different design parameters: collector size, air mass flow rate, and lava rock volume. From the study, the optimum efficiencies that were obtained in the range between the intensities of 500 W/m2 and 800 W/m2 were 62% to 64%, respectively, with an optimum flow rate of 0.035 kg/s. The optimum porosity of about 89% was selected for the collector by considering the pressure drop and thermal efficiency. An optimal temperature output range between 41.7 °C and 48.3 °C could be achieved and was suitable for agricultural and food drying applications. Meanwhile, compared to conventional DPSAHs, the average percentage increase in the output temperature of the DPSAH with lava rock was found to be higher by 17.5%.

Air-based solar collectors are the simplest forms of flat plate solar collectors; without complications of introducing water or nanofluids into the process. They are used to raise the entering atmospheric air temperature to a level where it can be used for different low and medium temperature applications. The main components of their design are the collector, absorber and airflow arrangement. However, they exhibit the lowest efficiencies among other collectors. Hence, V-groove absorber designs are implemented to raise the thermal efficiency of air collectors. In this paper, a parametric study on the thermal performance of single-pass solar air collector with a v-groove absorber has been conducted using theoretical model and ran numerically using an excel sheet. The v-groove will enhance the convective heat transfer of the collector; as it has superior performance to flat-plate collectors. Two different cover designs are proposed; one with glass cover and the other with Fresnel lens cover. A comparison of different parameters is presented for various design conditions and operating conditions to drive the efficiency with respect to mass flowrate and incident solar radiation. This paper differs from other works in the literature in that it presents comparison between Fresnel lens and glass cover for V-groove single pass air heater. The results obtained shows that at solar irradiance of 755 W/m2 the collector covered with Fresnel less has the highest efficiency value of 71.18% compared to solar collectors with glass which has efficiency 54.10%. The mass flowrate contributed to efficiency enhancement. Moreover, a case study for Bangi, Malaysia was conducted to numerically test the performance of the two types using real-data from an outdoors test. Highest achieved temperatures from both collectors were around 35.85 °C for the glass-covered type and 38.39 °C for the Fresnel lens covered type. Keywords: Air-collector, Glass cover, Fresnel lens cover, V-groove, Convective heat transfer

The existing literature in photovoltaic thermal (PV/T) collectors shows a promising development in this technology. The current markers for the technologies’ success are examined for various designs configurations and materials. However, the lack of an international standard to follow for PV/T installation, testing, and analysis may hinder the field from advancing to the next stage. In order to develop such standards, it is critical to establish a methodology for evaluating PV/T collectors. This paper examines existing evaluation criteria and proposes four novel methods for PV/T evaluation, namely yield per area/space, yield per weight, yield bias, and cost of yield. Outdoor experiments were performed in Bangi-Malaysia, as a proof of concept to the proposed criteria. The tested systems are (i) PV, (ii) Water-based PV/T and (iii) PV/T with Phase Change Material (PCM) and water as a coolant. Keywords: PV/T, Evaluation criteria, Yield per space, Yield per weight, Yield bias

The importance of utilizing the solar energy as a very suitable source among multi-source approaches to replace the conventional energy is on the rise in the last four decades. The invention of the photovoltaic module (PV) could be the corner stone in this process. However, the limited amount of energy obtained from PV was and still the main challenge of full utilization of the solar energy. In this paper, the use of the compound parabolic concentrator (CPC) along with the thermal photovoltaic module (PVT) where the cooling process of the CPC is conducted using a novel technique of water jet impingement has applied experimentally and physically tested. The test includes the effect of water jet impingement on the total power, electrical efficiency, thermal efficiency, and total efficiency on CPC-PVT system. The cooling process at the maximum irradiation by water jet impingement resulted in improving the electrical efficiency by 7%, total output power by 31% and the thermal efficiency by 81%. These results outperform the recent highest results recorded by the most recent work. Keywords: Photovoltaic thermal collectors, Electrical performance, Thermal performance, Compound parabolic concentrator, Jet impingement

Abstract High-performance perovskite solar cells have attracted increased attention for photovoltaic applications and potentially replacing the predecessor generations. Nevertheless, the stability issues and the lead content has always been among the major concerns that barriers perovskite solar cells from commercialization. This review presents the discussion towards the inherent instability of perovskite solar cells and the development towards replacing lead with discussion towards their performance and challenges. The degradation of perovskite active layer would release toxic substance into the environment. The development towards low-toxic, lead-free and efficient perovskite solar cells is the key for a sustainable solar energy generation with the application of perovskite solar cells.

In this study, chromium (Cr)-doped nickel oxide (NiO) thin films were deposited by employing selective lateral doping of Cr in NiO by radio-frequency magnetron sputtering at different doping times ranging from 0 s (undoped) to 80 s. The structural, optical, and electrical properties of the resulting Cr-doped NiO thin films were investigated. Structural investigation from XRD patterns indicated that the grown Cr-doped NiO layer crystallized in a cubic phase. Broadening of the diffraction peak with increasing doping time from 0 s to 80 s led to a reduction in the crystallite size that varied from 23.52 nm to 14.65 nm. Compared with the undoped NiO, the diffraction peak along the (200) plane shifted from left to right as a function of doping time. This result indicated that Cr+3 could easily enter the NiO lattice. Results from the Hall-effect study disclosed that electrical properties of Cr-doped NiO was highly dependent on doping time. The conductivity of NiO was increased with doping time, and the highest conductivity (8.73 × 10−2 Scm−1) was achieved at a doping time of 80 s. Finally, optical investigations revealed that as doping time increased, the optical bandgap of Cr-doped NiO films dropped from 3.43 eV to 3.28 eV. The highest Urbach energy at higher doping time indicated that crystallinity became poorer, and the degree of defects increased with increasing doping time.

The unprecedented development of perovskite-silicon (PSC-Si) tandem solar cells in the last five years has been hindered by several challenges towards industrialization, which require further research. The combination of the low cost of perovskite and legacy silicon solar cells serve as primary drivers for PSC-Si tandem solar cell improvement. For the perovskite top-cell, the utmost concern reported in the literature is perovskite instability. Hence, proposed physical loss mechanisms for intrinsic and extrinsic instability as triggering mechanisms for hysteresis, ion segregation, and trap states, along with the latest proposed mitigation strategies in terms of stability engineering, are discussed. The silicon bottom cell, being a mature technology, is currently facing bottleneck challenges to achieve power conversion efficiencies (PCE) greater than 26.7%, which requires more understanding in the context of light management and passivation technologies. Finally, for large-scale industrialization of the PSC-Si tandem solar cell, the promising silicon wafer thinning, and large-scale film deposition technologies could cause a shift and align with a more affordable and flexible roll-to-roll PSC-Si technology. Therefore, this review aims to provide deliberate guidance on critical fundamental issues and configuration factors in current PSC-Si tandem technologies towards large-scale industrialization. to meet the 2031 PSC-Si Tandem road maps market target.

An ideal n-i-p perovskite solar cell employing a Pb free CH3NH3SnI3 absorber layer was suggested and modelled. A comparative study for different electron transport materials has been performed for three devices keeping CuO hole transport material (HTL) constant. SCAPS-1D numerical simulator is used to quantify the effects of amphoteric defect based on CH3NH3SnI3 absorber layer and the interface characteristics of both the electron transport layer (ETL) and hole transport layer (HTL). The study demonstrates that amphoteric defects in the absorber layer impact device performance significantly more than interface defects (IDL). The cell performed best at room temperature. Due to a reduction in Voc, PCE decreases with temperature. Defect tolerance limit for IL1 is 1013 cm−3, 1016 cm−3 and 1012 cm−3 for structures 1, 2 and 3 respectively. The defect tolerance limit for IL2 is 1014 cm−3. With the proposed device structure FTO/PCBM/CH3NH3SnI3/CuO shows the maximum efficiency of 25.45% (Voc = 0.97 V, Jsc = 35.19 mA/cm2, FF = 74.38%), for the structure FTO/TiO2/CH3NH3SnI3/CuO the best PCE is obtained 26.92% (Voc = 0.99 V, Jsc = 36.81 mA/cm2, FF = 73.80%) and device structure of FTO/WO3/CH3NH3SnI3/CuO gives the maximum efficiency 24.57% (Voc = 0.90 V, Jsc = 36.73 mA/cm2, FF = 74.93%) under optimum conditions. Compared to others, the FTO/TiO2/CH3NH3SnI3/CuO system provides better performance and better defect tolerance capacity.

Tungsten disulfide (WS2) thin films were deposited on soda-lime glass (SLG) substrates using radio frequency (RF) magnetron sputtering at different Ar flow rates (3 to 7 sccm). The effect of Ar flow rates on the structural, morphology, and electrical properties of the WS2 thin films was investigated thoroughly. Structural analysis exhibited that all the as-grown films showed the highest peak at (101) plane corresponds to rhombohedral phase. The crystalline size of the film ranged from 11.2 to 35.6 nm, while dislocation density ranged from 7.8 × 1014 to 26.29 × 1015 lines/m2. All these findings indicate that as-grown WS2 films are induced with various degrees of defects, which were visible in the FESEM images. FESEM images also identified the distorted crystallographic structure for all the films except the film deposited at 5 sccm of Ar gas flow rate. EDX analysis found that all the films were having a sulfur deficit and suggested that WS2 thin film bears edge defects in its structure. Further, electrical analysis confirms that tailoring of structural defects in WS2 thin film can be possible by the varying Ar gas flow rates. All these findings articulate that Ar gas flow rate is one of the important process parameters in RF magnetron sputtering that could affect the morphology, electrical properties, and structural properties of WS2 thin film. Finally, the simulation study validates the experimental results and encourages the use of WS2 as a buffer layer of CdTe-based solar cells.