Efficiency Of Solar Modules Research Articles

Technical and Economic Analysis of Modernization of Solar Power Plant: A Case Study from the Republic of Cuba

The problem of increasing the efficiency of existing power plants is relevant for many countries. Solar power plants built at the end of the 20th century require, as their shelf lives have now expired, not only the replacement of the solar modules, but also the modernization of their component composition. This is due to the requirements to improve the efficiency of power plants to ensure the expansion of renewable energy technologies. This article presents a technical and economic analysis of the choice of solar power plant modernization method, which consists of (1) a method for calculating the amount of power generation; (2) the modeling of solar power plants under specific climatic conditions; (3) the analysis of electricity generation using different types of PV modules and solar radiation trapping technologies in Matlab/Simulink; and (4) the technical and economic analysis of a 2.5 MW solar power plant in the Republic of Cuba (in operation since 2015), for which four different modernization options were considered. All the scenarios differ in the depth of modernization; the results of the analysis were compared with the existing plant. The results of the study showed that the different modernization scenarios respond differently to changes in the inputted technical and economic parameters (cost per kWh, inflation rate, losses, and power plant efficiency). The maximum NPV deviations among the considered scenarios are: a 1% increase in inflation reduces NPV by 2%; a decrease in losses from 20% to 10% increases the NPV by 2.5%; a change in cost from EUR 0.05 to EUR 0.1 increases the NPV by more than 3.5 times. The dependence of the economic results was also tested as a function of three factors: solar module efficiency, inflation, and the price per 1 kWh. It was found that the greatest influence on the NPV of the proposed model is the price per 1 kWh. Based on this analysis, an algorithm was developed to choose the most effective scenario for the conditions of the Republic of Cuba for the modernization of the existing power plants.

Efisiensi Panel Surya Kapasitas 100 Wp Akibat Pengaruh Suhu Dan Kecepatan Angin

Solar radiation has a great effect on the output of the photovoltaic system. Wind speed is directly related to the cooling of the PV system and can also affect the performance of the solar collector. This research looks at the influence of temperature and wind on the efficiency of solar panels. From the results of the tests and calculations, it was found that the temperature of the single crystal panel measured on that day was 44°C, and the temperature of the polycrystalline panel was 43°C. The effect of wind speed on the efficiency of the solar module, calculated based on calculations using the linear regression method, shows a correlation level of R = 0.0281. This means that only about 2.81% wind speed will affect it. Has solar module efficiency. From the various aspects of the calculations carried out, we can see that the efficiency of the single crystal panel is 11.716%, while the efficiency of the polycrystalline panel is 10.02%. From the calculation results, we can conclude that the efficiency of the single crystal module is significantly increased.

Total solar spectrum energy converter with integrated photovoltaics, thermoelectrics, and thermal energy storage: System modeling and design

A total-spectrum-utilizing integrated photovoltaic (PV), thermoelectric (TEG), and thermal energy storage fluid (TES) solar energy converter (PV-TEG-TES) with novel device architecture is proposed, and its performance is modeled to demonstrate its viability and optimize its system-level design. By incorporating a top-layer GaAs PV, ultraviolet and visible light is absorbed and converted directly to electricity, while infrared radiation passes through the PV. This infrared radiation is then captured by the TEG and TES layers to supply additional electricity or to be stored as thermal energy. In addition, the TEG converts to electricity otherwise wasted heat from thermalization of photons within the PV layer, and the TES effectively cools the PV, keeping it within adequate operating temperatures. According to analysis predicting upper bound performance, this PV-TEG-TES device can outperform the electrical conversion efficiency of a single GaAs solar cell module by 1.9 percentage points (from 24.1% for PV alone to 26.0% for the combined device, a relative 7.9% improvement), and can convert and store a total of 79.3% of incident solar energy under a concentration ratio of 673 suns per direct solar spectrum. An analytical framework using a successive overrelaxation technique for solutions to the nonlinearly coupled radiative, thermal, fluid, and electrical phenomena in such a PV-TEG-TES device is also discussed, offering a starting point for practical device parameters.

Solar module orientation and tracking type performance and optimization

The efficiency and performance of solar cells and modules are typically evaluated and reported at normal incidence under peak solar radiation. We present a simple clear-sky model for solar irradiance that can be used to study the angular and annual performance of new photovoltaic materials. Using this model, we study the effect of solar module orientation for fixed-tilt module installations and different types of tracking (seasonal, 1D, and 2D) as a function of latitude. For fixed-tilt modules, the optimum tilt as a fraction of latitude varies from 0.83 at 1 deg to 0.73 at 60 deg. The effect of tilt misorientation for panels at the optimum azimuth is not very strong as the solar irradiance is about 94.5% of its optimum at ±20 deg mistilt. Both azimuth misorientation and tilt misorientation are studied. Optimized tilts and times of year for tilting are also obtained for modules that are seasonally adjusted twice and three times a year. The annual solar insolation of fixed modules is compared with modules that are seasonally adjusted twice and three times a year, continuously tracked in the north/south direction, continuously tracked in the east/west direction, and continuously tracked in two directions. The use of single-axis tracking in the east/west direction is preferable to north/south tracking and potentially improves overall energy collection by 16.2% to 31.0%. Continuous dual-axis tracking enhances overall annual energy collection by 36.0% to 45.5%. The model and provision of open source code provides for a way to assess the performance of new materials.

Facile fabrication of VO2/SiO2 aerogel composite films with excellent thermochromic properties for smart windows

In order to improve the solar modulation ability and near-infrared shielding performance of VO2-based films, in this work, VO2/SiO2 aerogel composite films have been fabricated by a facile mechanical ball-milling method. It has been clarified that the solar modulation efficiency (ΔTsol) of the composite film can be increased by 187.5% (from 6.4% to 18.4%) by introducing SiO2 aerogel into the composite film when the visible light transmittance (Tlum) is about 40%, which can be ascribed to the synergistic effect of Rayleigh scattering effect of SiO2 aerogel and the good dispersion of the particles. The VO2/SiO2 aerogel composite particles not only have excellent dispersion, but also the SiO2 aerogel can effectively slow down the oxidation of VO2 and improve the oxidation resistance of VO2. In particular, the universality of the Rayleigh scattering effect of SiO2 aerogel is demonstrated, which can act together with the doping effect of Mg2+ ions to further improve the thermochromic properties of VO2 films. This study provides a new idea for improving the thermochromic properties of VO2 films and meanwhile is of great significance in promoting the practical application of VO2 films in the field of smart windows.

Spectral conversion by silicon nanocrystal dispersed gel glass: efficiency enhancement of silicon solar cell

Alongside the quest for new materials for development of next-generation solar cells, increasing the efficiency of the existing crystalline silicon-based photovoltaic module is of paramount importance. In this work we prepared a silicon nanocrystal (NC) dispersed gel-glass and used it as a luminescent down shifting material to enhance the efficiency of a conventional solar cell module. The synthesized gel-glass efficiently converts the unutilized high energy UV photons of the solar spectrum to blue-green photons and renders them amenable for effective carrier generation. An exceptionally high quantum yield (42.8%) of photon down conversion could be achieved with the luminescent silicon NCs. Following the insertion of the NC embedded gel-glass, the relative photon conversion efficiency and the short circuit current of the solar cell were found to increase by 6.48% and 4.2%, respectively. Further improvement of solar cell efficiency using this material could be achieved by optimized design and deposition and by optimizing the formation parameters of the gel-glass.

Implementation of an Adaptive Neural Network-Based Controller for Improving the Conversion Efficiency of Solar Photovoltaic Module

Implementation of an Adaptive Neural Network-Based Controller for Improving the Conversion Efficiency of Solar Photovoltaic Module

Experimental Investigation of the Effect of a Combination of Active and Passive Cooling Mechanism on the Thermal Characteristics and Efficiency of Solar PV Module

A photovoltaic (PV) module’s electrical efficiency depends on the operating temperature of the cell. Electrical efficiency reduces with increasing PV module temperature which is one of the drawbacks of this technology. This is due to the negative temperature coefficient of a PV module which decreases its voltage significantly while the current increases slightly. This study combines both active and passive cooling mechanisms to improve the electrical output of a PV module. A heat sink made up of aluminum fins and an ultrasonic humidifier were used to cool the panel. The ultrasonic humidifier was used to generate a humid environment at the rear side of the PV module. The cooling process in the study was able to reduce the temperature of the panel averagely by 14.61 °C. This reduction led to a 6.8% improvement in the electrical efficiency of the module. The average power of 12.23 W was recorded for the cooled panel against 10.87 W for the referenced module. In terms of water consumption, a total of 1.5 L was approximately consumed during the whole experimental process due to evaporation. In effect, the proposed cooling approach was demonstrated as effective.

Analysis of temperature coefficients and their effect on efficiency of solar cell modules for photovoltaics-powered vehicles

Development of vehicles that are powered by photovoltaics (PV) is desirable, and is crucial for reduction in CO2 emissions from the transport sector to realize a decarbonized society. Our investigations show that the majority of the passenger cars that cruise only with solar energy can be realized by installing a high-efficiency PV module. Although the Toyota Prius demonstration car, which is equipped with a 860 W rated-output power PV module, has shown a 36.6 km d−1 PV-powered driving range at solar irradiance of 6.2 kWh m−2 d−1, practical driving ranges of PV-powered vehicles are shown to be shorter than the estimated values due to some losses of solar cell modules, such as temperature rise under sunny conditions. In this paper, we conduct a systematic analysis of the effects of these losses on the PV-powered driving range in order to obtain guidelines for the development of highly efficient solar cell modules for vehicle integrated applications. The analytical results show that the III–V compound solar cell modules have more suitable properties compared to other cells because of their higher potential conversion efficiencies of 37% with a smaller temperature coefficient of −0.19% °C−1 compared to −0.29% °C−1 for Si back contact solar cell modules and −0.26% °C−1 for Si heterojunction solar cell modules. Our theoretical calculations that take these losses into account suggest that installing the III–V-based triple-junction solar cell modules provides a potential PV-powered driving range of 30 km d−1 on average, and more than 50 km d−1 on a sunny day under the irradiation conditions in Japan.

Acid Solution Processed VO2-Based Composite Films with Enhanced Thermochromic Properties for Smart Windows.

As a typical thermochromic material, VO2 coatings can be applied to smart windows by modulating the transmission of near infrared (NIR) light via phase transition. However, the inherent undesirable luminous transmittance (Tlum) and solar modulation efficiency (ΔTsol) of pure VO2 impede its practical application. In order to solve this problem, the porous VO2 based composite film was prepared by magnetron sputtering and subsequent acid solution process with Zn2V2O7 particles used as a sacrificial template to create pores, which showed excellent Tlum (72.1%) and enhanced ΔTsol (10.7%) compared with pure VO2 film. It was demonstrated that the porous structure of the film caused by acid solution process could improve the Tlum obviously and the isolated VO2 nanoparticles presented strong localized surface plasmon resonance (LSPR) effects to enhance the ΔTsol. Therefore, this method will provide a facile way to prepare VO2 based films with excellent thermochromic performance and thus promote the application of the VO2 based films in smart windows.

INCREASING THE EFFICIENCY OF SOLAR ELECTRICAL PANELS BY CONVERTING THEM INTO HYBRIDS

Non-traditional energy has recently been more and more integrated into the modern energy system of Ukraine. The geographical location opens up great opportunities for the development of manyrenewable energy sources, including solar energy. In particular, Ukraine has already built some of the world's largest solar photovoltaic plants. However, their use is largely effective due to government subsidies in the form of a "green tariff" and other measures taken by the country's government. If these subsidies are reduced or eliminated, the use and construction of new such plants may be on the verge of recoupment. One of the main ways to increase their competitiveness is to increase the efficiency of using existing stations and introduce a universal low-cost solution for projected solar stations. The increase in the efficiency of solar photovoltaic modules is limited not only by design features, but also by the features of their application. At maximum illumination during the year, the most intense heating of these panels occurs. According to the technical characteristics of individual panels, the decrease in their effectiveness depends on their temperature coefficient. Direct cooling of the panels is an effective way to reduce the effect of this temperature coefficient. To improve these photovoltaic panels, it is proposed to turn them into a hybrid collector. To do this, a special transparent screen with a coolant circulating inside is fixed on the surface of the solar panel. The external arrangement of the screen offers a number of significant advantages over existing commercial hybrid collector models. Cooling the panel with this screen can result in a relatively large increase in power generation due to the intense cooling of the surface and the semiconductor elements themselves.

The experimental analysis of dust deposition effect on solar photovoltaic panels in Iran's desert environment

Since soiling is a site-specific problem, this paper for the first time performs controlled experiments to determine the characteristics of a dust sample from the desert region of Iran and its impact on the power efficiency of solar photovoltaic modules. Dust characterization experiments are performed using scanning electron microscope, X-ray fluorescence, and elemental mapping. Elemental mapping tests, which have attracted little attention in photovoltaic soiling studies, will help researchers to investigate this phenomenon more accurately. For electrical evaluations, general relationships between losses caused by dust deposition and degradation of photovoltaic output parameters are obtained by testing different dust samples. The elemental results showed that the dust sample is mostly composed of Si, O, Al, and Ca elements. In addition, indoor experiments revealed that dust particles have different shapes and sizes (from 0.4 μm to 31 μm). When the dust density is increased from clean cell to almost dark shading conditions, it was observed that conversion efficiency, photovoltaic normalized maximum power, open-circuit current, and short-circuits current are decreased by 98.2% (non-linearly), 98.13% (non-linearly), 20.63% (linearly), and 98.02% (non-linearly), respectively. Furthermore, the results showed that soiling process has no significant impact on fill factor due to uniform dust dispersion on PV module.

Thermochromic Ta Doped VO2 Films: Enhanced Luminous Transmittance, Significantly Depressed Phase Transition Temperature and Hysteresis Width

VO2 based films are considered as a promising thermochromic material for smart windows but not widely used due to their unbalanced thermochromic performance, in particular the relatively high phase transition temperature (Tc, ~68 °C). Herein, tantalum (Ta) doped VO2 films were fabricated by sol–gel method and the effects of Ta dopant on the thermochromic properties including metal-to-insulator transition (MIT) temperature, hysteresis width (ΔT), luminous transmittance (Tlum), and solar modulation efficiency (ΔTsol) were investigated for the first time. It is demonstrated that Tc and ΔT were decreased by approximately 8.0 °C and 2.4 °C/at.% Ta, respectively, which was attributed to the raised defects concentration derived from Ta doping. And the 4at.% Ta doped VO2 film exhibited Tc of 24.8 °C and an extremely narrow ΔT of 3.5 °C. Also, the film showed an enhanced Tlum of 47.1% compared with pure VO2 film (40.1%) while keeping ΔTsol beyond being impaired. The enhancement in optical properties is probably ascribed to the reduced particle size and widened optical bandgap. Therefore, this work could open opportunity to improve thermochromic performance of VO2 film in general, and provide insights into the relationship between the overall performance improvement and the structure variation induced by element doping.

Size-Controllable M-Phase VO2 Nanocrystals for Flexible Thermochromic Energy-Saving Windows

Ultrafine M-phase VO2 nanocrystals with good crystallinity are desirable for highly efficient thermochromic flexible films. Herein, we report an oxygen-controlled hydrothermal method to achieve the one-step preparation of stoichiometric and size-controllable VO2(M) nanoparticles for scaled-up production. The specific ratio of oxygen intake to V ions was first determined to guarantee the acquisition of stoichiometric VO2(M). Then, the hydrothermal conditions were optimized to perform size-controllable growth of VO2(M) nanoparticles. VO2(M) nanoparticles with average particle sizes of 25, 32, 41, and 52 nm were prepared by changing the precursor solution concentration under the determined oxygen intake/V ion ratio. Smaller VO2(M) nanoparticles exhibit better thermochromic performance because a smaller size favors light transmission and promotes blue-shifting of the local surface plasmon resonance. The flexible film fabricated with 25 nm VO2(M) nanoparticles shows an excellent thermochromic performance with a solar modulation efficiency (ΔTsol) of 19.2% and a luminous transmittance (Tlum) up to 66.42%. This work proposes a simple and effective hydrothermal process producing size-controllable VO2(M) nanoparticles with low cost and scalable production and demonstrates that the size reduction of VO2(M) nanoparticles is favorable for flexible films to exhibit excellent thermochromic properties.

Energy performance of window integrated photovoltaic system in actual operating condition

Standard test condition (STC) is widely used to measure the efficiency of solar photovoltaic modules. But, the specified values of different factors of this standard are rarely found in the actual field. Some of the crucial factors of the said standard are module temperature, angle of incidence (AOI), amount of incident solar radiation, and type of spectrum. This research paper presents the energy generation of a photovoltaic module integrated double pane window system under the effect of the above factors. The type of the considered photovoltaic module is thin-film semi-transparent made of Cadmium Telluride (CdTe). For the calculation, the material characteristics were initially processed using different software. The validity of the simulated values was checked with experimental findings. In the study, except the incident spectrum, all other factors found to affect the output negatively. For example, because of higher operating cell temperature, the decreases in energy generation ranges between 2.9% and 6.3% among the months in the year. Further, with the influence of the investigated factors, the considered STPV system is found to generate maximum energy of 95.3 kWh/m2 per annum. This energy generation is 10.5% less than the energy calculated using the conversion efficiency found at STC. One of the outcomes of this analysis is the incorporation of the combined effects of four critical factors in the energy generation of photovoltaic systems. The results and the method of this work provide a useful reference to the scientific community for the development of an improved testing procedure of solar photovoltaic modules.

VO2 nanostripe-based thin film with optimized color and solar characteristics for smart windows

This study presents a structuration approach to reach a high luminous transmittance (Tlum) and solar modulation efficiency (ΔTsol) of thermochromic vanadium dioxide (VO2) thin films. Before starting optical simulations, we confirm that the optical properties of monoclinic VO2 continuous films deposited by reactive magnetron sputtering show a good correspondence with numerical results. Then, calculations on ordered VO2 nanostripes demonstrate an enhanced transmittance due to the presence of vertical openings, leading to a variety of photonic effects. A series of optimizations by varying the column width, period, and film thickness establishes that 20 nm wide and 10 nm separated nanostripes have a ΔTsol of 14.2% and a Tlum of 47.6% for a film thickness of 250 nm. In comparison to a dense film without nanostructuring, the film transparency (related to Tlum) is significantly enhanced, while ΔTsol remains unchanged. Furthermore, this also translates into a favorable, less opaque color, so the geometry could be useful for various thermochromic applications, such as smart windows.

Integrating exceptional visible modulation, near-infrared shielding and energy storage in an all-solid-electrochromic bilayer device

A generic strategy of incorporating diverse functions in electrochromic dynamic windows is presented by sensibly choosing the individual layers of a bilayered active electrode. Here, all-solid electrochromic devices (ECD) with a remarkably high visible modulation (60–80%) and superior near-infrared (NIR) shielding performance (>90% full scale) were fabricated by simple solution-processing. The concept is demonstrated by selecting materials with identical chemical composition, i.e., porous amorphous-WO3 (a-WO3) coated on top of polycrystalline WO3·H2O nanosheets. These ECDs show four distinct voltage-selective modes in the ± 2.8 V range for enhanced privacy and energy saving. The IR modulation efficiency (IRME) of the devices stands at a record ~85%, with an outstanding solar modulation efficiency (SME) of ~63%. The initial energy storage estimations for the ECDs revealed superior volumetric stored charge density of ~400 Ccm−3@ 10 mVs−1, which is excellent for secondary energy sourcing. The fabricated EC glasses (with 50% usage) could directly save ~165 kWhm-2 yr-1 worth of energy by equating the energy-saving and generation. With reflected radiation reduction, the total saving may surpass the total energy generation from standard Si-Solar cells (~18% efficiency) of equal areal coverage.

Facile Preparation of Zn2V2O7–VO2 Composite Films with Enhanced Thermochromic Properties for Smart Windows

Usually, VO2 films prepared by a magnetron sputtering method exhibit good durability and excellent solar modulation efficiency (ΔTsol). However, its undesirable low-temperature luminous transmittan...

Affixing poly(methyl methacrylate-co-acrylic acid) nanospheres with trimethoxyvinylsilane on silicon solar module to enhance its power conversion efficiency

Poly(methyl methacrylate-co-acrylic acid) [P(MMA-co-AA)] incorporated with 0–9 wt% of trimethoxyvinylsilane (TMVS) has been studied to investigate the effect of TMVS on the adhesion properties of P(MMA-co-AA) nanospheres coated on silicon substrate as well as on the power conversion efficiency (PCE) of silicon solar module coated with the polymer nanospheres. The incorporation of 7 and 9 wt% of TMVS into the copolymer has been found to render the copolymer stronger adhesion to glass substrate than the samples with lower amount of TMVS in them. The coating of the P(MMA-co-AA) nanospheres on the glass surface of solar module increases the light harvesting efficiency by serving as an anti-reflective layer. Solar module coated with an array of P(MMA-co-AA) nanospheres with 7 wt% of TMVS yielded the highest PCE enhancement of 98% under the illumination of an AM1.5 solar simulator. The natural weathering results indicate that the copolymer with 7% of TMVS was able to withstand prolonged natural weathering exposure and remained reasonably effective in PCE enhancement up to 130 days of outdoor exposure. This study demonstrates a cost-effective technique to bind [P(MMA-co-AA)] nanospheres onto the silicon surface of solar module via siloxane linkages and thus increases the PCE of the solar module effectively. The Tg of the copolymer increased linearly from 110.31 to 118.42 °C when 0–9 wt% of TMVS was added into it. Thermogravimetry results indicate that the incorporation of TMVS does not give any significant effect on the Td of the copolymer, which occurs at about 390 °C.

Analysis of the influence of the ambient temperature on the energy efficiency of solar modules by application of empirical correlations for natural convection

In this paper, the effect of the ambient temperature on photovoltaic (PV) modules for different angles of inclinations and different intensities of the solar radiation on the surface of PV module is considered using empirical correlations for natural convection. The analysis used an analytical model based on the energy balance equilibrium between PV module and the environment. It has been shown that in real conditions of exploitation, the value of the solar conversion coefficient of the solar energy to be determined by the manufacturer, valid for the standard test conditions (STC) for PV module (25 °C -1000 W/m2). The results obtained indicates that in the case a smaller number of PV modules corresponding to the required number for average household. The proposed procedure can be applied in the techno-economic analysis for PV system with uniaxial monitoring of the sun position as well as static PV systems.