Photovoltaic Module Technologies Research Articles

Outdoor performance modeling of three different silicon photovoltaic module technologies

The accuracy of a two-diode model for three different photovoltaic module technologies, namely monocrystalline, amorphous and micromorphous silicon, has been investigated in this paper. The I–V and the P–V characteristics for each type of module were simulated using the specifications given by the module’s manufacturer in their datasheet at standard tests conditions. An accurate technique was used for calculating the corresponding irradiation absorbed by each module type. To validate the model, a comparison between the simulation results and the experimental data obtained for each PV module type tested in outdoor conditions for a sunny and a cloudy day has been carried out. A good agreement was found between the calculated and measured data, both for the I–V and the P–V curves and the characteristic points (Isc, Voc, Impp, Vmpp) under simultaneous variation of temperature and irradiation.

Performance assessment of five different photovoltaic module technologies under outdoor conditions in Algeria

The aim of this paper is to establish a performance assessment of different kinds of photovoltaic (PV) module technologies installed in the city of Saida in Algeria. The modules are three thin film modules: copper indium selenide (CIS), mono-crystalline heterojunction with intrinsic thin layer (HIT) and tandem structure of amorphous silicon and microcrystalline silicon (a-Si_μc-Si) with two crystalline silicon modules: multi-crystalline and mono-crystalline back contact. The modules were characterised by measuring their I-V characteristics under the same outdoor conditions. Moreover, measurements of various meteorological parameters such as irradiance, temperature and humidity, using the weather station, were also performed. The monthly average daily performance parameters as performance ratio, energy yield and efficiency are given and analysed. It was found that the HIT and the a-Si_μc-Si performed much better than the other technologies. The annual average daily performance ratios of a-Si_μc-Si module was found to be about 1.55% higher compared to HIT module and 2.04% compared to CIS. The HIT module produce an annual average daily energy of 1.15 kWh more than double what the a-Si_μc-Si produce and an annual average daily efficiency more than double of the efficiency of a-Si_μc-Si.

Assessment of implicit and explicit models for different photovoltaic modules technologies

Effective use of photovoltaic (PV) modules requires reliable models for a number of applications, such as monitoring the performance of PV systems, estimating the produced power and plant design, etc. Development of accurate and simple models for different PV technologies remains a big challenge. In this paper, a comparative study of seven implicit and explicit models, published in the literature, is presented. The predicted current-voltage characteristics of the main commercial PV module technologies (multi-crystalline Silicon, Copper Indium Gallium Selenide, and Cadmium Telluride), have been compared both with the ones from the datasheet and with the ones obtained experimentally. Moreover, the investigated models have also been evaluated in terms of accuracy, required parameters, generalisation capability and complexity.

Extraction of Saturation Current and Ideality Factor from Measuring Voc and Isc of Photovoltaic Modules

Saturation current (I0) and ideality factor (n) of a p-n junction solar cell are an indication of the quality of the cell. These two parameters are usually estimated from dark current-voltage measurements. In this study, a quick and easy method to determine these two parameters by measuring open-circuit, Voc, and short-circuit current, Isc, is presented. Solar cell designers can use this method as a grading or diagnostic tool to evaluate degradation in photovoltaic (PV) modules. In order to verify the Voc-Isc method, a series of experiments have been conducted on a single cell and a 36-cell module. Good agreement between our Voc-Isc method and dark I-V measurements was obtained. An application of the method on the performance degradation of a single-junction a-Si:H module revealed that the module’s I0 increased by more than three orders of magnitude and n increased by 65% after an outdoor exposure of 130 kWh/m2. This increase in n indicates that after exposure, the recombination current in the cells’ space charge region increased due to the light-induced formation of metastable defects. The method is also used to assess the quality of five PV module technologies and proved to be reliable despite defective cells in a module.

Performance Analysis and Comparison of Different Photovoltaic Modules Technologies under Different Climatic Conditions in Casablanca

The main goal of this work is to study the performance of silicon-based photovoltaic modules of different technologies (Monocrystalline (c-si), Polycrystalline (p-si) and Amorphous (a-si)) installed on rooftop of the Ben m’sik faculty at Hassan II university, Casablanca, Morocco (Latitude 33°36”N, Longitude 7°36”W). This study is based on daily measurements under various climatic conditions (clear, cloudy and rainy). In order to improve the performance evaluation, the real-time measurements were taken for every five minutes of different climatic parameters (solar irradiation, ambient temperature, module temperature, wind speed and direction) and electrical parameters (power, current and voltage). In fact, we studied the PV array efficiency, the inverter efficiency and the system efficiency. In addition, we performed an evaluation to the PV array, reference and final yields and the performance ratio (PR). The results show maximum values for module efficiency, final efficiency and system efficiency on a clear day for all three technologies due to high irradiation. The maximum values of PR are 72.10%, 91.53% and 86.20%, are obtained on a cloudy day, this is due to the low temperature and the high wind speed. Minimum values of PR, module efficiency, reference efficiency and final efficiency on a rainy day are due to the low sun exposure and the rain which affect the generated energy and stability of PV systems.

The synergistic effect of air mass on outdoor performance for different PV module in India

ABSTRACTThe effect of air mass (AM) on the performance of multi-crystalline silicon (m-Si), amorphous silicon (a-Si), and hetero-junction with intrinsic thin layer (HIT)-technology-based photovoltaic (PV) modules are evaluated for representative day of four seasons during the year 2011 for composite climate of India. To find the best performing PV module technology with respect to AM at the site, annual energy yields and performance ratio against different AM bands (AM 1–4.5) are plotted. It is found that HIT modules perform better than m-Si and a-Si at each AM band. Annual energy yields for all three technologies decrease with increasing order of AM bands. The performance ratio for HIT and m-SI modules initially increases and then decreases with increasing order of AM bands. However, for a-Si modules, the performance ratio decreases with increasing order of the AM bands.

Energy learning curves of PV systems

The energy demand of photovoltaic (PV) systems is an important part of energy sustainability of PV systems. PV systems are considered sustainable energy systems when the produced energy is higher than the energy needed for the PV system on a life‐cycle basis. This paper employs financial learning curve concepts to determine the energy demand of major PV module technologies and systems. General PV module and PV system energy learning curves are calculated by weighting energy demand of different PV systems according to their share in PV market. Additionally, the contribution of module efficiency for reducing specific energy demand is considered. We find an energy learning rate of 17% for PV modules and 14% for PV systems on the basis of a market weighted mix of technologies and volumes. Energy payback time (EPBT) and energy return on energy investment (EROI) in 2010 and for the year 2020 are calculated via the energy learning rate and indicates a further significant progress in energetic productivity of PV systems. To the knowledge of the authors this publication shows for the first time that the energy consumption in PV manufacturing follows the log‐linear learning curve law similar to the evolution of production cost. This allows calculating EPBT or EROI for future prognoses. Furthermore, it shows significant evidence of how sustainable PV systems are and justifies their growing share in the energy market. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 914–923, 2016

Multi-Variable Bifacial Photovoltaic Module Test Results and Best-Fit Annual Bifacial Energy Yield Model

Bifacial photovoltaic cell and module technology have been well understood for many years and produced in quantity by companies, such as Sanyo/Panasonic, Hitachi, PVGS, BSolar, Yingli, and LG. While manufacturers are already producing bifacial modules, there is slow adoption into the market place due to a deficiency in standardized testing and modeling techniques used to predict the performance of bifacial systems. As such, Prism Solar conducted a multi-variable, multi-site testing program to determine the impact that common installation variables have on the yearly energy output of its bifacial solar modules. The effects of the module’s minimum height ratio, tilt angle, and ground albedo on the annual energy output were studied through direct field measurement. Based on these results, a best-fit model that links these variables to the annual energy output is presented. We believe this is the largest single collection of bifacial experiments presented to date, and one of the first general bifacial energy models publicly disclosed for general use. In addition, a comparison of the results of using this best-fit bifacial energy yield model derived by the authors with third-party bifacial data is also presented; this serves to validate the authors’ model and adds to the utility of this paper by presenting and combining multiple sources of bifacial data.

Semi-empirical single diode model and verification to common photovoltaic module technologies

This paper proposed an improved semi-empirical single diode photovoltaic (PV) module model over single-diode five parameter (Rp) model. Rp-model is considered as a compromise in simplicity and accuracy among other models, however, it has drawbacks on deviation from actual value at low irradiance level. The proposed semi-empirical Rp-model (SE-Rp) is to improve the drawback by considering the simplicity and accuracy features of Rp-model. Model verification has been done for six different PV modules of three common manufacturing technologies: mono-crystalline, poly/multi-crystalline and thin-film silicon. I-V characteristic and absolute error plots revealed significant improvements of the proposed model over Rp-model.

Effect of seasonal spectral variations on performance of three different photovoltaic technologies in India

The accuracy of outdoor performance of a photovoltaic (PV) array can be improved by considering the spectral effects. In this paper, the impact of seasonal spectral variations on the three different silicon PV tech- nologies: single junction amorphous silicon (a-Si), Hetero- junction with Intrinsic Thin-layer (HIT) and multi crys- talline silicon (mc-Si) has been presented first time in Indian environmental conditions. The spectral effect on HIT PV module technology has been presented first time along with the first simultaneous study of variation in spectral indicators by useful fraction (UF), average photon energy (APE) and spectral mismatch factor (MMF), based on monthly and seasonal data. The maximum observed variation in UF was 26.4, 8.2, 10.8 %, while in MMF, variation was up to 24.7, 7.6, 8.2 % for a-Si, HIT and mc- Si, respectively, and in APE variation was up to 15.3 %. Among all three technology modules, first time reported HIT technology showed the least variation while maximum variation was observed in a-Si technology. The observed spectral effect variations have been discussed on Perfor- mance Ratio and compared with reported results of other global sites. The value and trends of spectral parameters are important to understand the effect of spectral variation on different technology. This study is especially important in Indian subcontinent perspective because of the strong monsoon season, where observed variation in the spectrum-related parameter found to be highest among all the seasons.

Comparison of photovoltaic and solar thermal cooling systems for office buildings in different climates

Photovoltaic systems combined with electrical compression chillers offer a high potential for energy efficient cooling with a high economic feasibility. Due to much higher energy efficiency ratios of electric chillers compared to sorption cooling systems, the heat rejection system is much smaller and thus auxiliary energy and water consumption lower than in sorption cooling systems. The overall system efficiency, auxiliary energy consumption and achievable solar fraction depend on the photovoltaic module technology, the compression chiller energy efficiency ratio and obviously on the temporal correspondence of solar cooling production and cooling demand. A systematic simulation study was carried out to evaluate the overall performance of photovoltaic compression cooling systems in office buildings for different climatic conditions worldwide. For each location and cooling demand the solar energy production for different surface areas was calculated and solar fractions, EER and auxiliary energy demand was determined. It could be shown that the primary energy savings for solar electric cooling and heating are comparable to solar thermal systems. As solar thermal systems include hot storage, they mostly provide higher solar fractions and in some cases higher primary energy savings. If electricity export to the grid or for appliance use is included in the primary energy analysis, photovoltaic cooling systems always have higher primary energy savings.The total cooling costs for solar electric cooling are comparable to solar thermal cooling systems, if there is no feed in tariff for the excess PV electricity. If a grid export is possible and paid for, solar electric cooling systems are always more advantageous.

태국 열대몬순기후 조건에서 PV모듈 기술별 성능특성 비교 연구

The performances of three different types of photovoltaic (PV) module technologies namely, copper-indium-diselenide (CIGS), mono-crystalline silicon (mo-Si) and amorphous silicon (a-Si) have been comparatively studied in the grid-connected system for more than a year under the tropical monsoon climate of Thailand. The yields, performance ratios and system efficiencies for the respective PV module technologies have been calculated and a comparison is presented here. The performance ratios of the initial operation year for CIGS showed highest among the compared technologies under Thailand climate conditions by marking 97.0% while 89.6% for a-Si and 81.5% for mo-Si. Although mo-Si has shown highest efficiencies all over the period, under the testing conditions, the operating efficiency of mo-Si was down-graded from its reference value mainly due to high operating temperature and the efficiency of the tested CIGS module was also found as high as that of mo-Si in the study. Accordingly, outdoor assessment shows that CIGS modules have demonstrated high performance in terms of yields and performance ratios in Thailand climate conditions.

Performance Degradation of Various PV Module Technologies in Tropical Singapore

The performance of ten photovoltaic (PV) modules with nine different solar cell technologies (and one different module construction) is monitored in the tropical climate of Singapore. The types of modules included in this study are monocrystalline Si (glass-backsheet with frame and glass-glass without frame), heterojunction crystalline Si, monocrystalline Si back-contact, multicrystalline Si, double-junction “micromorph” Si, single-junction/double-junction amorphous Si, CdTe, and CIGS. Three years of outdoor monitoring data are used to extract degradation trends of the performance of the various modules. Statistical decomposition methods are used to extract trends for performance ratio (PR), short-circuit current (I SC ), open-circuit voltage (V OC ), and fill factor (FF). The degradation rates of the monocrystalline Si modules are found to be equal to or less than -0.8% per year, mainly contributed by the decrease in I SC . The multicrystalline Si module shows a slightly higher degradation rate of -1.0% per year. The amorphous Si, micromorph Si, and CdTe modules show degradation rates of around -2% per year. The CIGS module showed an exceptionally high degradation rate of -6% per year. The decrease in FF and VOC is found to be significant for all the thin-film modules but not for the crystalline silicon modules.

Effect of Solar Spectrum on the Performance of Various Thin-Film PV Module Technologies in Tropical Singapore

The spectral influence on the performance of four different thin-film photovoltaic (PV) modules (single-junction amorphous Si, CdTe, CIGS, and double-junction “micromorph” Si) is studied. Two methods are used to quantify the effective irradiance intensity for the investigated four modules. The first is based on spectral mismatch factors calculated from the measured outdoor spectrum and the spectral responses of the PV modules. The second is based on the measured short-circuit currents of the modules. The effective irradiance ratio (EIR) of a PV module technology, for a given time period, is defined as the ratio between the cumulative effective irradiance intensity received by the module and the cumulative irradiance intensity measured by a c-Si reference cell. We find that the average photon energy of the spectrum in Singapore is higher than that of the AM1.5G reference spectrum, indicating that the spectrum is “blue-rich.” Compared with the AM1.5G spectrum, this blue-rich spectral irradiance results in an annual EIR of 1.07 and 1.03 for the single-junction a-Si module and the CdTe module, respectively. An EIR larger than 1 indicates energetic irradiance gain. CIGS is not significantly affected by the blue-rich spectrum, while micromorph Si shows an annual EIR of less than 1.

Operational experienced of an 8.64 kWp grid-connected PV array

The Department of Agricultural Machinery of the University of Debrecen has a photovoltaic (PV) system. Information’s are given about the main operational characteristics and operation experiences. In this research, evaluation of 3 PV modules technologies i.e. monocrystalline PV technology (ST-40), polycrystalline PV technology (KC-120), and amorphous silicon PV technology (DS-40) performed based on points of view energetic in 2011. The produced DC, and AC power, together with the produced energy are as well, and the efficiency can be determined for each used PV technology.

Energy performance of different photovoltaic module technologies under outdoor conditions

A comparative study is performed to obtain the energy performance of four different photovoltaic module technologies, when they are exposed to the same real sun conditions over a one-year period under the meteorological conditions of Southern Spain. Modules of thin film technologies were analysed: amorphous silicon (a-Si), tandem structure of amorphous silicon and microcrystalline silicon (a-Si/μc-Si) and cadmium telluride (CdTe). In addition, a polycrystalline silicon module (pc-Si) was studied. The modules were characterised by measuring their I–V curve. Thin film modules show changes of the peak power at STC (Standard Test Conditions) throughout the year. This variation is more remarkable in a-Si modules. The performance comparison shows that the perfomance of thin film modules is better than that of pc-Si modules for this location. However, CdTe and pc-Si modules present better performances during the winter months with higher daily yield values and lower total losses, while a-Si and a-Si/μc-Si modules perform better in summer. This paper also presents an empirical model that allows the daily energy performance of different module technologies to be calculated according to the daily irradiation and to the daily average temperature of the module. The proposed empirical model has an average relative error under 5% for all analysed modules.

Investigation of building integrated photovoltaics potential in achieving the zero energy building target

Since the photovoltaic (PV) scientific community started exploring innovative ways of incorporating solar electricity into buildings, a whole new vernacular of solar electric architecture emerged. Currently, there is a growing consensus that building integrated photovoltaics (BIPV) systems will be the backbone of the zero energy building (ZEB) European target by 2020, through their widespread commercialization. BIPV systems often produce however less energy than conventional PV systems due to architectural constraints in the design of BIPV arrays. This paper presents a conceptual study regarding the energy yield and feasibility of BIPVs in several locations in Europe. Specific conclusions on the energy yield and economic feasibility of BIPVs with regard to the implemented PV module technology, the climatic zone, the orientation of the building and the mounting disposition are drawn. The findings of this work that were also validated using hourly time step computational analysis, reveal the necessary conditions under which BIPVs could have a major contribution to fulfilling the European 2020 targets by enabling the achievement of the ZEB goal.

Multilayer perceptron applied to the estimation of the influence of the solar spectral distribution on thin-film photovoltaic modules

In this paper, we propose the use of a methodology to characterise the electrical parameters of several thin-film photovoltaic module technologies. This methodology allows us to use not only solar irradiance and module temperature as classical models do, but also spectral distribution of solar radiation. The methodology is based on the use of neural network models. From all measured I–V curves of a module, a previous selection of them has been used in order to train the neural network model. This selection is performed using a Kohonen self-organising map fed with spectral data. This spectral information has been added as an input to the neural network itself. The results show that the incorporation of spectral measurements to simulate thin-film modules improves significantly both the fitting of the predicted I–V curve to the measured one and the peak power point estimation.

Investigation of the Performance of Commercial Photovoltaic Modules under Tropical Conditions

The tropical regions will see an increasing share of solar photovoltaic (PV) applications. This paper therefore analyses the irradiance distribution in tropical Singapore and then experimentally determines the dependence of the PV efficiency on irradiance level, for nine different commercially available PV module technologies. For several of the PV module technologies, we also determine the dependence of the temperature coefficient of the modules' maximum power on the irradiance level. A full year of outdoor module testing data in Singapore show that the irradiance distribution has two energy peaks, one at around 400 W·m-2 and the second at around 850 W·m-2. Most PV technologies cannot fully convert the second peak due to the fact that, in Singapore, high light intensities are always associated with higher module temperatures, which in turn reduces the module efficiencies.

Investigation of the Performance of Commercial Photovoltaic Modules under Tropical Conditions

The tropical regions will see an increasing share of solar photovoltaic (PV) applications. This paper therefore analyses the irradiance distribution in tropical Singapore and then experimentally determines the dependence of the PV efficiency on irradiance level, for nine different commercially available PV module technologies. For several of the PV module technologies, we also determine the dependence of the temperature coefficient of the modules' maximum power on the irradiance level. A full year of outdoor module testing data in Singapore show that the irradiance distribution has two energy peaks, one at around 400 W·m-2 and the second at around 850 W·m-2. Most PV technologies cannot fully convert the second peak due to the fact that, in Singapore, high light intensities are always associated with higher module temperatures, which in turn reduces the module efficiencies.