Photovoltaic Cell

We have synthesized new carbazole and ethylenedioxythiophene based molecular glasses with hydrazone and imine goups. Thermal analysis confirms the metastable amorphous properties of these molecules with glass temperature in the range of 62 to 76 °C. Electrochemical properties have been studied and show the effect of the conjugated imine or hydrazone groups on the electronic delocalization of the structures. A decrease of the oxidation potential, compared to the parent unsubstituted molecules, is observed, which decreases the HOMO energetic level and improves the donor properties of the molecules. Amorphous materials of low molecular weight should allow the regeneration of the oxidized sensitizer in agreemen t with their respective energetic levels. Moreover, all the molecules absorb light in the range of th e wavelength, blue-shifted in comparison with the ruthenium dye, which limits the shield effect for a good photogeneration of charge carrier in the dye. Results suggest that such...

paper  can  be  assisted  and  will  save  time  of building  a  literature about  PV  by  this  review  that  is considered  part  of  a  series  compares  the  performance  of  PV technologies.  In  this  paper,  a  comparison  survey  is  included which  investigates  the  3  generations  of  PV  cells  with  the  latest characteristics.

Zhvillimi i qëndrueshëm përmes përdorimit të energjive të rinovueshme është sot një përparësi për çdo vend. E tillë është energjia diellore dhe shfrytëzimi i saj përmes shumëllojshmërisë së sistemeve fotovoltaike dhe transformimi i saj në energji elektrike. Kjo mundësohet me një sërë procesesh si efekti fotoelektrik, gjysëmpërçuesat dhe kalimit p-n të elektroneve, vrimave dhe së fundi lindjes së rrymës elektrike. Studimi paraqet mundësinë e shfrytëzimit për nevoja shtëpiake të energjisë diellore përmes sistemit “on grid” dhe “off grid” të sistemeve fotovoltaike të një banesë me një terracë 75.95m2 duke përllogaritur sasinë e energjisë elektrike që kjo banesë shpenzon. Përllogaritja e kostove të vendosjes së paneleve fotovoltaike per të njëjtën sipërfaqe terrace tregon se mbulohen kostot e shpenzimit  dhe se për rreth 8 vite e mbulojmë investimin ndërsa garancia e tyre shkon deri në 15 vjet, pra mund të shfrytëzojmë energji falas përreth 7 vjet.

At an industrial scale, the front side metallization of solar cells is performed by screen printing for 40 years. A silver-based paste is printed before a high temperature annealing. This simple and robust process enables a high throughput. However, the metallization is a critical step in production lines. On the one hand, the contact properties affect the final cell performances. On the other hand, the photovoltaic industry already accounts for 7% of the world's silver consumption. With the expected exponential growth of this sector, the mass of silver per cell becomes crucial as it governs their final cost. Consequently, it is mandatory to optimize the screen printing process to limit the amount of deposited silver and maximize the solar cell efficiency. The first part of this study focused on these two aspects. First, the rheological behavior of screen printing pastes is investigated. Then, a multifactorial study is combined with power loss simulations to assess the effect of screen printing parameters on the cell efficiency and the deposited silver mass. Besides, these studies have lead to an average cell efficiency of 19,0% at an industrial scale. To ensure the photovoltaic industry growth, the screen printing process should be replaced in coming years. Indeed, the heterogeneous contact microstructure causes significant electrical losses in comparison to high-efficiency cells. Moreover, the limited resolution of this process does no longer allow a contact width reduction, which has a direct impact on the optical losses and the silver mass per cell. Finally, the simultaneous optimization of the electrical and geometrical contact properties is difficult at an industrial scale. The seed and plate concept is an innovative solution that overcomes these limitations. First, a seed layer is printed to reduce the initial contact width and improve its interface with the cell. Then, a second layer is electrolytically grown to improve the conductivity and the height of the metal grid. Besides, this step enables an accurate control of the deposited silver amount. Several solutions are available to print the first layer. Because of a high throughput and flexibility, the flexographic printing process seems particularly well suited to meet the seed layer requirements at an industrial level. The second part of this study focuses on the development of this process. First, the rheological behavior of several inks is studied. Secondly, the flexographic printing process is adapted to print fine lines that can be thickened by light induced plating (LIP). The potential of this metallization scheme is then assessed using a simulation of cell performances and silver consumption. Finally, a promising 17,9% cell efficiency demonstrates the concept feasibility.

Solar energy is the most important renewable source of energy. The demand of Photovoltaic system is due to the fact that they produce electric power without hampering the environment. Solar PV modules directly convert solar energy into electrical energy. Solar energy is clean and completely natural energy. By using the Solar Tracking System solar module able to maintain the position that sun's rays are always perpendicular to it. Solar Tracking system increases the output from of solar module. This paper reviews the progressive development of the technology used for solar tracking system. This paper also tries to emphasize the various practices and methods to promote the benefits of solar tracker and also discusses other techniques to increases the efficiency of solar module.

A high-performance, ultralight, photovoltaic concentrator array is being developed for space power. The stretched lens array (SLA) uses stretched-membrane, silicone Fresnel lenses to concentrate sunlight onto triple-junction photovoltaic cells. The cells are ...

Abstract Renewable energy sources are being progressively more used for providing energy needs due to the growing concern of environmental pollution. Photovoltaic (PV) systems have a significant place within the renewable energy sources. Solar cells are the ...

Anatase TiO2 displaying dual morphologies were synthesized with a simple chemical route via a single step. A strong correlation between the dye sensitized solar cell (DSSC) device performance and the obtained dual morphologies are highlighted using relevant evidences from UV-vis and diffuse reflectance spectroscopy (DRS), Raman analysis, field emission scanning electron microscope, high resolution transmission electron microscope, current-voltage characteristics and impedance analysis. Structural investigation revealed that the interested medium in this work employed for the synthesis of TiO2 produced different types of dual morphologies such as nanospheres with nanoparticles (NSNP), microsphere decorated with nanoparticles (μSNP) and nanoparticles with stone like features (NPS). UV-vis and DRS results indicated the ability of the materials to assist with diffused reflectance and optical absorption of the screen printed photoanodes. In addition, an investigation of Raman vibrational characteristics was carried out in detail using synchronous and asynchronous 2D correlation analysis. The high intense Eg anatase mode of Raman spectrum was simulated using a phonon confinement model and its normalised spectra are compared with an experimental data. The resultant performances in the DSSCs were not indicative by the material properties; so, the charge transfer resistance (Rct) and recombination properties of the photoanode were investigated. These results showed that the Nyquist plot of NSNP possesses the smallest diameter, which reveals that the device based on NSNP offers the lowest Rct value that accounts for the higher conversion efficiencies when compared with the DSSC device based on photoanodes μSNP and NSP. It can be concluded that the improved power conversion efficiency shown by photoanode fabricated using NSNP has the dual role of optimum surface area for dye loading and light scattering centres. These properties, when optimized along with the offered pathway for electrolyte diffusion to the dye degeneration with less Rct, could lead to better photoelectric conversion efficiency.

— All PV module's datasheets provide I-V curve as well as the values of selected parameters at Standard Test Conditions (STC). Other parameters such as series resistance (Rs), shunt resistance (Rsh), photocurrent (Iph), diode reverse-saturation current (Io) and ideality factor (a) are not measurable. Therefore, they are not provided by manufacturers. These parameters are unique for the electrical characterization of any PV module. Based on the parameters Iph, Io, Rs, and Rsh, four equations are formed and used to obtain an exact, closed-form expression for Rs that solved numerically while increasing the value of a in small increments. To validate the proposed approach, a set of I-V curves are obtained at different values of a, and compared to the reference curve given by the manufacturer, then the parameters that corresponds to the curve that fits closest are taken. This process is done for BP SX150 and MSX60 solar modules. The proposed algorithm is compared with alternative methods available in the literature. The superiority of the proposed algorithm is verified.

This study investigates ultra-thin transparent conducting oxides (TCO) of indium tin oxide (ITO), aluminum-doped zinc oxide (AZO) and zinc oxide (ZnO) to determine their viability as candidate materials for use in plasmonic-enhanced thin-film amorphous silicon solar photovoltaic (PV) devices. First a sensitivity analysis of the optical absorption for the intrinsic layer of a nano-disk patterned thin-film amorphous silicon-based solar cell as a function of TCO thickness (10–50 nm) was performed by simulation. These simulation results were then used to guide the design of the experimental work which investigated both optical and electrical properties of ultra-thin (10 nm on average) films simultaneously deposited on both glass and silicon substrates using conventional rf sputtering. The effects of deposition and post-processing parameters on material properties of ITO, AZO and ZnO ultra-thin TCOs were probed and the suitability of TCOs for integration into plasmonic-enhanced thin-film solar PV devices was assessed. The results show that ultra-thin TCOs present a number of challenges for use as thin top contacts on plasmonic-enhanced PV devices: (1) optical and electrical parameters differ greatly from those of thicker (bulk) films deposited under the same conditions, (2) the films are delicate due to their thickness, requiring very long annealing times to prevent cracking, and (3) reactive gases require careful monitoring to maintain stoichiometry. The results presented here found a trade-off between conductivity and transparency of the deposited films. Although the sub 50 nm TCO films investigated exhibited desirable optical properties (transmittance greater than 80 %), their resistivity was too high to be considered as materials for the top contact of conventional PV devices. Future work is necessary to improve thin TCO properties, or alternative materials, and geometries are needed in plasmonic-based amorphous silicon solar cells. The stability of ultra-thin TCO films also needs to be experimentally investigated under normal device operating conditions.

There is significant interest in harvesting ocean energy for powering the autonomous vehicles that can conduct surveillance for long durations. In this paper, we analyze the applicability of solar cells as a power source for medusa-inspired biomimetic vehicles. Since these vehicles will be operating under ocean waters and may need to dive at various depths, a systematic investigation was conducted to determine the variation of output power as a function of depth and salinity levels. We modeled solar energy harvested by flexible amorphous solar cell coated jellyfish vehicles by considering the variables bell diameter, turbidity, depth, and fineness ratio. Low fineness ratio shapes were found to be better for solar energy powered vehicles. Study of three representative species, Aurelia aurita (AA), Mastigias sp., and Cyanea capillata indicates that harvested power was proportional to bell diameter. Optimum power can be harvested by tilting the vehicle axis to face refracted sunrays. Depending on a swimming pattern, power harvested in charging mode and in propulsion mode could vary significantly. The model indicates that, under some circumstances, amorphous silicon solar cell may be a cost-effective way to power autonomous underwater vehicles (AUVs) operating in shallow-water conditions with large lateral travel distances.

— [pt]: Este trabalho objetiva uma maior compreensão do uso da energia solar para gerar eletricidade, assim como ter uma idéia da relevância da energia elétrica na sociedade atual, e as possibilidades de geração de eletricidade tanto por meios heliotérmicos como fotovoltaicos, suas características básicas, componentes essenciais de cada um dos sistemas, caracterização visual de coletores e painéis solares, diagramas básicos de ligação dos sistemas elétricos solares, etc.

— [fr]: Ce travail vise à mieux comprendre l'utilisation de l'énergie solaire pour produire de l'électricité, ainsi qu'à se faire une idée de la pertinence de l'énergie électrique dans la société d'aujourd'hui, et des possibilités de produire de l'électricité à la fois par des moyens héliothermiques et photovoltaïques, ses caractéristiques de base, essentielles chacun des systèmes, caractérisation visuelle des panneaux solaires et des collecteurs, schémas de base pour connecter les systèmes électriques solaires, etc.

— [en]: This work aims at a greater understanding of the use of solar energy to generate electricity, as well as to have an idea of the relevance of electric energy in today's society, and the possibilities of electricity generation by both heliothermic and photovoltaic means, its basic characteristics, essential components of each of the systems, visual characterization of solar panels and collectors, basic diagrams for connecting solar electrical systems, etc.

Band gap engineering provides an opportunity to not only provide higher overall conversion efficiencies of the reference AM1.5 spectra but also customize PV device design for specific geographic locations and microenvironments based on atmospheric conditions characteristic to that particular location. Indium gallium nitride and other PV materials offer the opportunity for limited bandgap engineering to match spectra. The effects of atmospheric conditions such as aerosols, cloud cover, water vapor, and air mass have been shown to cause variations in spectral radiance that alters PV system performance due to both overrating and underrating. Designing PV devices optimized for spectral radiance of a particular region can result in improved PV system performance. This paper presents a new method for designing geographically optimized PV cells with using a numerical model for bandgap optimization. The geographic microclimate spectrally resolved solar flux for twelve representative atmospheric conditions for the incident radiation angle (zenith angle) of 48.1° and fixed array angle of 40° is used to iteratively optimize the band gap for tandem, triple, and quad-layer of InGaN-based multijunction cells. The results of this method are illustrated for the case study of solar farms in the New York region and discussed.

Maximum power point tracking following (MPPT) is by and large being utilized in sunlight based photovoltaic (PV) control age frameworks to augment sun-based vitality extraction. In this paper, it is proposed to work the solar-PV framework at the imperfect MPPT to oversee control balance in a remote area control supply (RAPS) framework. This is performed dependent on three diverse working modes one is Frequency control mode, second is Active power control mode and the third one is MPPT control mode. The working modes are chosen dependent on the heap level, and the working method of the diesel generator (for example synchronous condenser mode or generator mode) This power the executive's methodology adjusts the age and load request that requires progress between the three working modes without utilizing the fake load. The proposed strategy is capable of extending the diesel generator lifetime and improves the operating efficiency of the diesel generator. Re-enactment thinks about are done to approve the adequacy of the imperfect MPPT control methodology in a PV-Diesel RAPS framework and have demonstrated that the proposed technique can flawlessly keep up the power balance in the RAPS framework while keeping up the voltage and recurrence inside stipulated cutoff points. Substantial cost savings can also be achieved in the long run due to the lifetime extension and efficiency improvement of the diesel generator.