Binary composite (TiO2-Gr) based nano-enhanced organic phase change material: Effect on thermophysical properties

The latent heat storage technology using Phase Change Materials (PCMs) has recently been extensively utilized in energy conservation and management to reduce energy consumption. To improve the thermal conductivity of PCMs, they have been incorporated with nanoparticles. In this article, we report, Titanium dioxide-Graphene (TiO2:Gr) binary composite (1 wt% TiO2: 0.1, 0.5, 1 and 2 wt% of Graphene (Gr)) with Paraffin wax (PW) to improve the thermophysical properties added with sodium dodecylbenzene sulphonate (SDBS) as surfactant. Ultraviolet-visible spectrometer (UV–VIS), Fourier transform infrared spectroscopy (FT-IR), Differential scanning calorimeter (DSC), Thermogravimetric analyzer (TGA), Field Emission Scanning Electron Microscopy (FESEM) and Thermal property analyzer (TEMPOS) were used for material characterizations. The latent heat capacity of the PW/Titanium oxide (TiO2) composite and the PW/TiO2-Gr binary composites were improved by 8.62% and 10.02%, respectively, in comparison to base PCM. The thermal conductivity of the composite PCMs with PW/TiO2-1.0 and PW/TiO2Gr-1.0 is 120% and 179% higher than base PW. The FT-IR spectra demonstrated no chemical interaction between the PW and the nanoparticles. TGA results presented improved thermal stability by integration of the TiO2-Graphene particles into the matrix of paraffin wax. The light transmission of the prepared composite was reduced by 58.30% related to base PW, resulted increased light absorption and, subsequently, enhanced photothermal conversion. The composite's improved thermal conductivity and enthalpy make it a strong contender for use in TES and solar photovoltaics thermal systems

Experimental and simulation-based comparative analysis of different parameters of PV module

enewable Energy (RE) has been rapidly growing day by day as a need of the world due to the energy crises and environmental effects. In recent years, the use of solar systems for the generation of electricity has gained considerable popularity. This increase mainly results from a scarcity of other energy sources, such as fossil fuels. As a result, there is a pressing need to transition to more dependable and long-term resources, such as photovoltaic (PV) systems. To improve the performance of PV proper design and development have been required for adequate extraction of their essential parameters. This study proposed the implementation and behaviour of a photovoltaic module (PVM) and describes the individual main equation situated on the Shockley diode to enable a detailed study of semiconductor physics and PV occurrence. The environmental performance of a PVM is represented using MATLAB which can be illustrative of the PVM for simple use in the simulation phase. The model was designed in MATLAB, an easy-to-use icon and dialog box that depends on the effect of solar radiation (SR) and cell temperature, output current (I) versus (vs) voltage (V), and power vs. Voltage. PVM is made with the simulated models are simulated and optimized. These models have been used to analyze the outcome of variations in various specifications on the PVM, including the operating temperature and the level of SR. The observed results have been compared with outcomes characteristics of PV, which are specified on the technical datasheet of the PVM. Simulation results have been obtained by using MATLAB software. From the results, it can be seen that at insolation 900W/m2 the output power of PVM is 280 but at 10°C the power of PVM is 270

Thermal conductivity and Thermal properties enhancement of Paraffin/Titanium Oxide based Nano enhanced Phase change materials for Energy storage

The Latent heat storage (LHS) based on phase change materials (PCMs) has a critical part to demonstration in preserving and efficiently utilizing energy, resolving demand-supply mismatches, and boosting the efficiency of energy systems. However, they have a low thermal performance inherent in it because the low thermal conductivity (TC) of PCMs. Paraffin organic PCMs have several advantages such as higher LHS, nontoxic, abundant in nature and inexpensive, whereas TiO2 nanoparticle is type of hydrophilic group having tendency to improve TC. In this research TiO2 in different concentration (0.1, 0.5, 1, and 2 wt percent) with surfactant sodium dodecyl benzene sulphonate (SDBS) added into Paraffin RT44 HC PCM using two step techniques, and the thermophysical properties were broadly discussed. Thermogravimetric analyzer (TGA), Fourier transform infrared spectroscopy (FT-IR) and Thermal property analyzer (TEMPOS) were used for the characterization of prepared composite nano-enhanced phase change materials (NePCM). Additionally, the effect of nanoparticles on TC was investigated. The highest TC was obtained with PW/TiO2-1.0 by an increment of 86.36% as related with base PW. The FTIR spectrum of the composite PW/TiO2 confirmed no interaction between PW and TiO2, resulting in a more chemical stable composite. The addition of TiO2 to PW enhance the degrading temperature 10 C by making it more thermal stable. Grounded on the results it can be concluded that the developed composite is suitable for thermal energy storage (TES), photovoltaic thermal (PVT) systems, and hot water applications

Electrical and thermal performance assessment of photovoltaic thermal system integrated with organic phase change material

The integration of photovoltaic (PV) system in power system proved to be potential technology in terms of renewable energy sources. However, photovoltaic system has major drawback of rise in cell temperature, which results in low power production and reduced service life. To overcome the temperature rise in photovoltaic system, the addition of water cooling and phase change materials installed at rear side PV system termed as photovoltaic thermal (PVT) system has been adopted in this study. The organic phase change material (RT-42) having melting temperature of 42 °C and water cooling running at 0.45 litre per minute (LPM) under 440 W/m2 irradiation has been taken as input parameters. The photovoltaic system and water cooled photovoltaic system performance has been analysed by using real time solar simulator. Additionally, the PVT-PCM system is assessed by use of TRNSYS simulation. Finally, this study compares the thermal and electrical efficiency of PV, PVT, and PVT-PCM systems. The findings indicated that maximum temperature for PV cells in a PV system was 59 °C. Water cooling alone reduces the temperature down to 49 °C, whereas water cooling combined with phase change material (PVT-PCM) lowers it down to 36°C. Further, the heat gain of 189 watt and 191 watt was achieved for PVT and PVT-PCM system. Additionally, the PV, PVT, and PVT-PCM systems achieved electrical efficiencies of 6.1%, 7%, and 9.5%, correspondingly

Thermal energy harvesting of highly conductive graphene-enhanced paraffin phase change material

Solar energy is the most plentiful renewable energy source that has the capability to keep up with the growing demand. When the sun’s energy is not available, thermal energy storage (TES) using phase change material (PCM) is a promising technique for storage and utilization. However, PCM’s low thermal conductivity may limit its use. The use of nanomaterials to enhance the thermal conductivity is one of the prominent solutions to overcome this issue. This research work reports that graphene nanoparticles (0.1%, 0.3%, 0.5%, 0.7% and 1% mass) enhanced paraffin wax (PW) to improve the thermophysical properties and transmittance capability. Thermogravimetric analyzer (TGA), differential scanning calorimeter (DSC), Fourier transform infrared spectroscopy (FTIR) and ultra-violet visible spectroscope (UV–VIS) were used for the characterization of the base PCM and nano-enhanced phase change materials (NePCM) composites. A significant improvement of 110% in thermal conductivity was obtained at 0.7% mass ratio compared to base PW without compromising the prepared composites’ latent heat storage (LHS) capacity. TGA and FTIR outcomes demonstrated excellent thermal and chemical stability, respectively. To check the thermal reliability of composite, the PW and nanocomposite were subjected to repeated thermal cycling. The outcome evidence that the NePCM composite had consistent thermal energy storage properties even after repeated thermal cycles. The composite’s light transmission was drastically lowered by 56.34% (PW/Gr-0.5) compared to base PW, resulting in PW/Gr composite has better thermal reliability in relation to thermal conductivity and LHS than base PCM, which can be used specifically in photovoltaic thermal systems and TES

Thermal energy harvesting of highly conductive graphene‑enhanced parain phase change material

Solar energy is the most plentiful renewable energy source that has the capability to keep up with the growing demand. When the sun’s energy is not available, thermal energy storage (TES) using phase change material (PCM) is a promising technique for storage and utilization. However, PCM’s low thermal conductivity may limit its use. The use of nanomaterials to enhance the thermal conductivity is one of the prominent solutions to overcome this issue. This research work reports that graphene nanoparticles (0.1%, 0.3%, 0.5%, 0.7% and 1% mass) enhanced paraffin wax (PW) to improve the thermophysical properties and transmittance capability. Thermogravimetric analyzer (TGA), differential scanning calorimeter (DSC), Fourier transform infrared spectroscopy (FTIR) and ultra-violet visible spectroscope (UV–VIS) were used for the characterization of the base PCM and nano-enhanced phase change materials (NePCM) composites. A significant improvement of 110% in thermal conductivity was obtained at 0.7% mass ratio compared to base PW without compromising the prepared composites’ latent heat storage (LHS) capacity. TGA and FTIR outcomes demonstrated excellent thermal and chemical stability, respectively. To check the thermal reliability of composite, the PW and nanocomposite were subjected to repeated thermal cycling. The outcome evidence that the NePCM composite had consistent thermal energy storage properties even after repeated thermal cycles. The composite’s light transmission was drastically lowered by 56.34% (PW/Gr-0.5) compared to base PW, resulting in PW/Gr composite has better thermal reliability in relation to thermal conductivity and LHS than base PCM, which can be used specifically in photovoltaic thermal systems and TES

Extraction of cellulose from bagasse for the synthesis of Alginate:Cellulose porous beads

This study aimed to develop the production of porous cellulose beads from bagasse. Alkali extraction with 6% sodium hydroxide was identified as the optimal solvent for cellulose, based on the swelling ratio. This process resulted in viscose cellulose solution with improved characteristics, including a density of 1.099 g/ml, viscosity of 0.024 Pa·s, molecular weight of 171.668 g/mol, and a swelling ratio of 50.8%. The beads fabrication using the cellulose extract combined with alginate led to the formation of beads with a homogeneous and rough surface. Calcium carbonate (CaCO3) was utilized as a porogen and zinc acetate served as the crosslinking agent. The optimal composition of alginate to cellulose xanthate for bead formation, determined through evaluations of bead geometry, swelling power, and surface porosity using SEM-EDX, was found to be a 2:2 ratio

Advancements in PV-thermal systems with and without phase change materials as a sustainable energy solution: energy, exergy and exergoeconomic (3E) analytic approach

Photovoltaic thermal (PVT) systems are increasingly becoming an essential part of the solar application systems integrating the photovoltaic (PV) and solar thermal collectors into a single unit to produce heat and electrical energy from the intermittent solar irradiation. Energy systems are usually analyzed by energy and exergy analyses. Most of these systems are designed considering their energy performances based on the 1st law of thermodynamics. Generally, the energy reduction occurring in systems can be detected using exergy analysis and is a valuable tool for investigating the energy efficiency of energy systems, thereby helping the complicated thermodynamic systems more efficient. The exergoeconomic analysis is a form of economics focused on exergy analysis and is a hybrid of exergy and cost analysis to enhance the output of PVT systems. This allows designers to determine strategies to enhance the system efficiency from its cost perspective. Herein, a detailed literature review on energy, exergy and exergoeconomics (3E) analysis and their applications in air-based, water-based and bi-fluid PVT systems with and without integrated phase change materials (PCMs) is executed. It was found that water-based PVT systems with PCMs (PVT-PCM) are more feasible as the energy and exergy efficiencies are enhanced and their energy payback time reduced as compared to other conventional systems. The energy and exergy efficiencies of the water-, air- and bi-fluid-based PVT systems integrated with PCMs were found to be higher than the systems without PCM integration. PCM integration with a water-based PVT system can lead to the storage of thermal energy and also enhance the overall exergetic efficiency of the system up to 25%. The exergy efficiencies of PVT systems were found to be between 3–14%, and generally less than their energy efficiencies. Thus, 3E analysis is found to be a more technical approach to assess the performance of PVT systems and gives a complete overview of the performance of the system

Energy, exergy, exergoeconomic and enviroeconomic (4-E) assessment of solar water heater with/without phase change material for building and other applications: a comprehensive review

Solar water heating is the most common method of using solar energy because of its technical viability and economic attractiveness. However, intermittent nature of solar energy and lack of energy storage limits use of Solar Water Heaters (SWHs). Phase change materials (PCMs) utilize the heat energy from the solar energy effectively. Integrating PCMs to SWHs overcome the limitation of limited use in the day time only and make it more efficient and user friendly. The main objective of this review paper is to review a broad variety of work on the energy, exergy, exergoeconomic and enviroeconomic (4E) approach of with and without PCMs integrated SHWs for building and other applications in recent years and to address the technical challenges associated with SWH systems. This review paper discusses the recent advances, practical techniques, appropriate specifications of solar water heating systems with and without phase change materials based on 4E (energy, exergy, exergoeconomic and enviroeconomic) analytical approach. It has been observed that solar water heater combined with PCMs are more efficient in terms of energy and exergy efficiency and energy payback period