PERFORMANCE OF DIFFERENT PHOTOVOLTAIC TECHNOLOGIES FOR AMORPHOUS SILICON (A-SI) AND COPPER INDIUM GALLIUM DI-SELENIDE (CIGS) PHOTOVOLTAIC MODULES

In this work, the analysis of performance of two types of photovoltaic (PV) (Amorphous Silicon (a-Si) Copper Indium Gallium Diselenide (CIGS) technologies were achieved out under under Iraqi (Baghdad)climate conditions. The elevation of the selected site is 9 m above ground level. The experimental work covered the eight commercially available PV technologies. The two technologies that employed in this work are, Amorphous Silicon (a-Si) and Copper Indium Gallium Diselenide (CIGS). The total period of the experimental work was 7 months, and the data were analyzed simultaneously. Special attention is given to the influence of temperature and solar radiation the performance of the PV modules. Where, it was proposed a simple I-V curve test for PV modules. The results showed that the proposed system successfully experimentally extracted I-V curves of the selected two PV modules (amorphous and CIGS solar modules). The maximum values of power (Pmax) at solar radiation intensity 750 W/m² are 2.742 W, and 2.831 W for amorphous silicon and copper indium gallium di-selenide respectively. This is occurred because the lowest solar module operating temperature (19 oC and 17 oC for solar radiation 750 and 1000 W/m2 respectively) and ambient temperature (7 oC) and for Jan., 2021 than other months. Consequently, the same behavior for the two modules at solar irradiance 1000 W/m2 with the highest power value; 2.680 W, and 3.198 W of amorphous silicon and copper indium gallium di-selenide respectively. Furthermore, the minimum values of power (Pmax) at solarradiation intensity 750 W/m² are 2.530, and 2.831 for amorphous silicon and copper indium gallium di-selenide respectively because we have the highest solar module operating temperature (57 oC, and 55 oC respectively) and ambient temperature (45 oC) for April, 2021 than other months. Consequently, the same behavior for the two modules at solar irradiance 1000 W/m2 with the highest power value; 2.680 W, and 3.198 W of amorphous silicon and copper indium gallium di-selenide respectively. The highest efficiency can be notes for CIGS solar module with a value 7.3%, while the lowest one is 5.5% for amorphous solar module.

CIGS Photovoltaics: Reviewing a Evolving Paradigm

Copper indium selenide chalcopyrite-structure alloys with gallium (CIGS) are unique among the highest performing photovoltaic (PV) semiconductor technologies. They are structurally disordered, nonstoichiometric materials that have been engineered to achieve remarkably low bulk nonradiative recombination levels. Nevertheless, their performance can be further improved. This review adopts a fundamental thermodynamic perspective to comparatively assess the root causes of present limitations on CIGS PV performance. The topics of selectivity and passivation of contacts to CIGS and its multinary alloys are covered, highlighting pathways to maximizing the electrochemical potential between those contacts under illumination. An overview of absorber growth methods and resulting properties is also provided. We recommend that CIGS researchers consider strategies that have been successfully implemented in the more mature wafer-based GaAs and Si PV device technologies, based on the paradigm of an idealized PV device design using an isotropic absorber with minimal nonradiative recombination, maximal light trapping, and both electron-selective and hole-selective passivated contacts. We foresee that CIGS technology will reach the 25% efficiency level within the next few years through enhanced collection and reduced recombination. To significantly impact power-generation applications, cost-effective, manufacturable solutions are also essential.

Enhancing Precursor Quality of Cu-In-S Ternary Thin Films by Applying More Appropriate Deposition Procedure

Copper indium sulphur (CIS) thin films were electrochemically grown from an acidic aqueous solution including 10 mM CuCl2, 10 mM InCl3, 20 mM Na2S2O3 and 200 mM LiCl. Deposition potential is determined by means of cyclic voltammetry analysis. The precursor CIS thin films are produced at -1.10 V for 600 s, -0.90 V for 300 s and a mixed potential of -0.25 V for 150 s and -1.10 V for 150 s. It is reported that surface morphology and film stoichiometry vary remarkably with the deposition parameters. SEM images show a variation in the grain shape, homogeneity and agglomeration due to the different Cu/In ratio. The produced films have XRD peaks belonging to both CIS2 crystalline phase and S element. The produced CIS material at -1.1 V has a band gap of 1.66 eV. The CIS thin film produced at -0.9 V has three different band gaps such as 1.76, 2.59 and 2.85 eV. The CIS material produced by two steps has also three different band gaps between 1.59 and 2.74 eV. The CIS films are p-type, and resistivity and mobility data are in the range 6.56-8.61 Ωcm and 8.68-22.2 cm2/Vs, respectively. It is found that the acceptor concentration of CIS thin films varies between 2.48x1017 and 1.06x1018 cm-3. In summary, this study reports a procedure to produce high-quality precursor CIS thin films, highlighting a promising material to be used in heterostructure photovoltaic devices as a p-type absorber layer.

Annealing Studies of Copper Indium Oxide (Cu2In2O5) Thin Films Prepared by RF Magnetron Sputtering

Copper indium oxide (Cu2In2O5) thin films were deposited by the RF magnetron sputtering technique using a Cu2O:In2O3 target. The films were deposited on glass and quartz substrates at room temperature. The films were subsequently annealed at temperatures ranging from 100 to 900 °C in an O2 atmosphere. The X-ray diffraction (XRD) analysis performed on the samples identified the presence of Cu2In2O5 phases along with CuInO2 or In2O3 for the films annealed above 500 °C. An increase in grain size was identified with the increase in annealing temperatures from the XRD analysis. The grain sizes were calculated to vary between 10 and 27 nm in films annealed between 500 and 900 °C. A morphological study performed using SEM further confirmed the crystallization and the grain growth with increasing annealing temperatures. All films displayed high optical transmission of more than 70% in the wavelength region of 500–800 nm. Optical studies carried out on the films indicated a small bandgap change in the range of 3.4–3.6 eV during annealing.

REDUCING CLIMATE CHANGE BY INSTALLING A NEW PHOTOVOLTAIC POWER PLANT IN BULGARIA

Three new roof-mounted 10 kWp grid-connected photovoltaic (PV) power plants have been constructed in the Technology Park at the Technical University of Gabrovo, Bulgaria, as part of a project "Competence Center – Intelligent Mechatronic, Eco, and Energy Saving Systems and Technologies". Three different PV modules types have been used: monocrystalline silicon (mono-Si), cadmium telluride (CdTe), and copper indium gallium selenide (CIGS). New three power plants, together with the existing amorphous silicon and poly-crystalline silicon photovoltaic power plants at the TU-Gabrovo enhanced simultaneous testing of five different photovoltaic materials. A small 500 Wp mono-Si photovoltaic thermal hybrid solar collectors (PVT) PV system has also been constructed. The power plants feature a monitoring system for the meteorological and electrical operating parameters, which measures, displays, and stores data on solar radiation, temperature, wind speed, currents, voltages, and electrical power of each power plant. PV plants components' technical characteristics are given in the paper. The schemes describing the basic wiring diagram, disposition of the three PV subsystems on the roof of the building at the technology center have also been presented. The initial comparative software data for monitoring of meteorological and electrical operating characteristics of the three different types of PV subsystems are shown as well. According to the specific ecological equivalent of energy resources and energy for the region of Bulgaria, the data are presented on the saved CO2 emissions from the avoided production and transmission of electricity owing to the operation of photovoltaic power plants.