Investigation of Underperformance in Fielded N-type Monocrystalline Silicon Photovoltaic Modules

This chapter is addressed at analyzing how the performance of some photovoltaic (PV) materials is influenced by the solar spectrum distribution according to the months of the year. Spectral responses of four different PV technologies—amorphous silicon, cadmium telluride, copper indium diselenide, and monocrystalline silicon—have been used to develop this study. Spectra and incident global irradiance were scanned at 5-min intervals in two inland sunny sites located in Spain during a 12-month experimental period. Regarding the results, it was concluded that amorphous silicon and cadmium telluride PV modules undergo the highest differences of monthly spectral gains over the year. Much slighter seasonal variations of these gains are perceptible in the other two considered PV technologies. Specifically in the two locations analyzed, spectral gains range from approximately − 12 % (January) to around 2 % (June) for the amorphous silicon (a-Si) PV module while such gains range from values close to 0 % (April to September, inclusive) to values slightly lower than − 2 % (December) for the copper indium diselenide (CIS) and monocrystalline silicon (m-Si) PV module. Prevailing “red-rich” and “blue-rich” spectra in winter and summer, respectively, could explain these results.

Photovoltaic (PV) modules' degradation behaviour, together with outdoor field condition and fault diagnostics, consist valuable data in evaluating efficiency and establishing long-term reliability of a PV system. However, since PV modules commonly come with 25 (even over) years of warranty, testing modules in field for that long period is not feasible. Thus, due to time constraints, many accelerated aging tests have been recently introduced for testing reliability and durability of PV modules. Scope of the presented study is the assessment of the performance degradation and fault (defect) propagation mechanisms with regard to three monocrystalline silicon (mc-Si) PV modules, through a specific thermal cycle accelerated ageing test. The parameters that were experimentally evaluated towards the accelerated ageing process of this study, were: i) the thermal signature evolution and/or propagation of any diagnosed defects, especially in two modules, by means of infrared (IR) thermographic measurements, ii) the overall performance degradation of each module, by means of electrical I-V measurements, together with iii) specific morphological characteristics, by means microscopy imaging. The intended study gave useful and promising results in assessing the effect of the applied thermal cycles upon the modules’ thermal behaviour, electrical efficiency and morphology.

The long-term degradation of photovoltaic (PV) modules under real operating conditions remains a critical factor for accurately assessing lifetime energy yield and economic performance. In this study, the field performance of thin-film cadmium telluride (CdTe), polycrystalline silicon (poly-Si), and monocrystalline silicon (mono-Si) photovoltaic modules was evaluated after 15 years of continuous outdoor operation in a temperate continental climate in Southeastern Europe (Sliven region, Bulgaria). All modules were installed at the same site and operated under identical mounting and environmental conditions, enabling a direct comparison between technologies. The results after electrical characterization reveal a total efficiency reduction of 12.3% for CdTe modules, corresponding to an average degradation rate of approximately 0.82% per year. In contrast, polycrystalline silicon modules exhibit a significantly lower efficiency loss of 1.2% (≈0.08% per year), while monocrystalline silicon modules show the lowest degradation, with only a 0.4% decrease over the 15-year period (≈0.03% per year). Visual inspection identified localized degradation features, including surface alterations and defects, which serve as qualitative indicators of long-term material aging. The findings indicate that crystalline silicon technologies demonstrate substantially higher long-term stability than thin-film CdTe modules under moderate continental climatic conditions. The presented long-term field data contribute to improved understanding of climate-specific degradation behavior and support more accurate lifetime performance modeling for photovoltaic systems in similar environments.

The solar photovoltaic (PV) cell converts solar energy into electricity with a relatively low efficiency which is <15%. More than 80% of the absorbed solar energy is dumped into the surroundings as heat after photovoltaic conversion. The operating temperature of the photovolatic module should be maintained as low as possible to improve the efficiency. This research work proposes recycle water-cooled solar photovoltaic system design by using a mono-crystalline and amorphous silicon PV module as solar absorber. Recycle water cooling of a normal amorphous and crystalline PV module configured as water base solar PV system by forced flow is studied. The energy and exergy performance of the PV module has been experimentally determined at 3.5 l/min (210 l/h) mass flow rate. The experimental result shows that the water-cooled solar PV module has got better performance than the PV module without cooling. Around 4.5% of amorphous and 3.2% of mono-crystalline module energy efficiency improved on cooling along with 6.5% of amorphous and 5% of mono-crystalline module exergy efficiency improvement with respect to without cooling/normal solar PV module.

Performance of 5 photovoltaic (PV) modules made of different technologies (monocrystalline silicon, polycrystalline silicon, amorphous silicon, copper indium selenide and heterojunction with intrinsic layer) is evaluated according to the short-term capacity evaluation method described in IEC TS 61724-2 standard. Measurements for the analysis are obtained from the data acquisition system developed by the Laboratory for Renewable Energy Sources at the Faculty of Electrical Engineering, Computer Science and Information Technology (FERIT) Osijek which is described in the paper. Results of the performance analysis according to the IEC TS 61724-2 standard indicate that the copper indium selenide PV module Solar Frontier SF150-S has the greatest performance, therefore it is the most suitable PV module for the micro-location of Osijek, Croatia with European humid continental climate. The lowest performance of all studied PV modules is achieved by polycrystalline silicon PV module Bisol BMU 250. Empirical analysis of the relations of various electrical and meteorological parameters is performed and dependencies are evaluated. In the last section, mathematical models of PV module efficiency in relation to the module temperature are derived based on empirical analysis of measurements.

The rapid growth of photovoltaic (PV) installations in recent years has largely been driven by government incentive schemes that make PV an attractive option for building owners seeking to reduce their greenhouse gas emissions and energy costs. As government incentives are reduced or withdrawn the incorporation of battery storage, to lower building electricity grid imports through increased on-site PV self-consumption, is an option to sustain rooftop PV uptake. This study combines a life cycle assessment approach and discounted cash flow analysis to assess the CO2 and financial impact of adding battery storage to a PV assemblage in the context of future incentive withdrawal, electricity system decarbonisation and changing technology costs. An example non-domestic building in the UK with a 20 kW mono-crystalline silicon PV and lithium-ion battery storage is modelled. With electricity grid decarbonisation in line with the Paris Climate Change Agreement, the PV and battery system here reduces the building's CO2 emissions by 17% (19tCO2) compared with the grid-only reference over a 30year lifetime. The analysis also highlights that adding battery storage does not necessarily increase C02 savings achieved by PV alone for the building, if grid decarbonisation is considered. PV systems without batteries in the UK are however found to be viable in 2020 without government incentives. For system considered here the battery costs of <£334/kWh available capacity are needed in 2020 for batteries to positively affect the financial performance of PV. The study therefore concludes that UK battery costs have to continue to reduce rapidly, or additional revenue from providing electricity system services is needed to make batteries financially attractive in lower insolation areas like the UK. Policy to reduce electricity system CO2 through building integrated battery uptake requires better understanding of the net system CO2 impact in line with other changes in electricity generation and demand.

Investigation on the operating characteristics of a directly-attached light crystalline silicon PV roof

Smart cities integrate a wide and diverse set of small electronic devices that use Internet communication capabilities with very different purposes and features. A challenge that arises is how to feed these small devices. Among the various possibilities, energy harvesting presents itself as the most economical and sustainable. This paper describes the design and simulation of an electronic circuit dedicated to maximizing the solar power extraction from photovoltaic (PV) modules. For this purpose, an integrated circuit (IC) dedicated to energy harvesting is used, namely the LTC3129. This IC is a DC-DC converter that uses the maximum power point control (MPPC) technique, which aims to keep its input voltage close to a defined reference value. The designed circuit is used with three photovoltaic modules, each one of a different PV technology: monocrystalline silicon, polycrystalline silicon and amorphous silicon. These PV modules are installed in a weather station to correlate the power produced with the meteorological conditions, in order to assess which solar photovoltaic technology is best for a given location. The equivalent circuit of a solar cell is used in simulation to represent a photovoltaic module. The values of the components of the equivalent circuit are adjusted so they have the same characteristics of the modules installed in the weather station. With each module, a power resistor of the same value is used as load, for comparison purposes. For the case of the monocrystalline silicon technology, the use of the LTC3129 converter increases the power extraction by 47.6% compared to when this converter is not used between the PV module and the load.KeywordsPhotovoltaic modulesDC-DC converterMaximum power point controlLTSpice softwareLTC3129 DC-DC converter

The optical and electrical effects of hydrogenaterd silicon nitride (SiNx:H) films deposited on N-type FZ silicon wafers by radio frequency remote plasma enhanced chemical vapour deposition (RF-RPECVD) technique were investigated. Optical reflectance, effective minority carrier lifetimes, bond density and SiNx:H/Si interfacial properties are evaluated after SiNx:H deposition. The dependence on gas flow ratio was estimated. In addition, the effect of thermal annealing on effective minority carrier lifetime improvement was examined. Effective minority carrier lifetimes were improved after deposition and further improvement of exceeding chemical passivation (CP) was realized after forming gas annealing in N2 ambient. Improvement of effective minority carrier lifetime after annealing correlates to transfer of hydrogen atoms in SiNx:H film. Reflectance was reduced to values lower than 1% at wavelengths near 600-800nm. Refractive index of the deposited SiNx:H films ranged 1.8- 2.1 and increased with increasing SiH4 flow rate. Film thickness ranged 73-97nm and decreased with increasing SiH4 flow rate.

Deformation behaviors and inverse Hall-Petch effect in nanoindentation of silicon: An atomistic simulation study with experimental validation

The analysis of different PV power systems for the determination of optimal PV panels and system installation—A case study in Kahramanmaras, Turkey

Polymer components, in particular, backsheets (BSs) and ethylene‐vinyl acetate (EVA) encapsulants, play a crucial role in the degradation of commercial silicon photovoltaic (PV) modules. Degradation mechanisms depend in a complex way on the composition and properties of all involved polymers. In this study, we demonstrate that differences in the composition of EVA encapsulants, in particular, the presence of additives, such as UV blockers, affect the degradative processes in a decisive way, even for modules with identical BSs. A combination of spectral, imaging, and electrical characterization techniques applied in a mixed lab/field study showed that the field aging of PV modules with the same BSs and different encapsulant components results in the development of different degradation signs, such as insulation resistance loss, corrosion of metal interconnects, water ingress, oxidation depth in the encapsulant, and potential‐induced degradation, depending on the presence of additives in the encapsulant. The present study provides an outlook on the complex influence of polymer components on the lifetime and performance of silicon PV modules.

This study provides a comparative assessment of the performance of monocrystalline silicon(mono-Si), polycrystalline silicon (poly-Si), and thin-film amorphous silicon (a-Si) photovoltaic modules under Burkina Faso’s distinct climatic zones. Using long-term satellite derived irradiation and temperature data from 1994 to 2015, system conversion efficiency, energy yield, and performance ratio are evaluated across semi-arid, arid, humid subhumid, and dry subhumid regions. Results indicate that mono-Si modules achieve the highest energy output in all zones (up to 425.9 kWh.m2 in arid regions), followed by poly-Si and thin-film modules. However, thin-film technologies exhibit superior performance ratios (up to 0.96), indicating better tolerance to high temperatures. The findings highlight the trade-off between efficiency and environmental resilience, offering data-driven recommendations for PV technology selection in hot and dusty climates of West Africa. This research contributes to optimizing solar energy deployment in regions with high solar potential but challenging environmental conditions.

In recent years, the increasing interest in energy production from renewable energy sources has led to photovoltaic elements being placed on greenhouse coverings. The shading of crops by these elements can, however, cause problems regarding the normal course of agricultural activity. All studies thus far on the application of photovoltaic (PV) panels as a greenhouse covering material have focused on flat roof structures. Tunnel greenhouses, due to their curved shape, do not lend themselves easily to accommodating PV panels on even part of the cover. In this study, we analysed the shading variation inside a tunnel greenhouse that was produced by applying flexible and transparent PV panels in a checkerboard arrangement. The transparent flexible PV panels are manufactured using monocrystalline silicon cells, with an efficiency of 18%, incorporated into polymers with high resistance. The PV panel dimensions are 1.116×0.165 m. The simulation software Autodesk® Autocad2010® was used for this study. The variation and distribution of the shading percentage of PV panels were analysed in relation to the surface area affected by the photovoltaic roof, the total area of the greenhouse and the section of the greenhouse. In particular, we studied the variations in the percentage of shading and the size of the shaded area on the twenty-first day of each month of the year. The results show some regularity in the shading percentage, mainly due to the curvilinear shape of the section of the greenhouse. From mid-March to mid- September, the shading in the middle of the day is almost always inside the greenhouse. In the other months of the year, it is partly inside and partly outside the tunnel greenhouse. With the photovoltaic arrangement adopted, the percentage of shading during the year never exceeds 40%.

Description of short circuit current of outdoor photovoltaic modules by multiple regression analysis under various solar irradiance levels