This paper reviews the energy yield enhancement characteristics of bifacial photovoltaic systems combined with solar tracking, focusing on their performance relative to conventional monofacial fixed-tilt configurations. The fundamental mechanisms of yield improvement are summarized, highlighting the largely additive contributions of solar tracking, which increases front-side irradiance, and bifacial modules, which utilize rear-side reflected and diffuse radiation. Reported results from previous studies indicate that bifacial systems with single-axis tracking typically achieve 25–35% higher annual energy yield compared with standard monofacial fixed-tilt systems, with variations depending on environmental and design conditions. Key design and environmental considerations influencing system performance are discussed to provide practical insights for the application of bifacial tracking systems in utilityscale photovoltaic installations.

Organic photovoltaics (OPVs) are attractive candidates for sustainable energy conversion due to their flexibility, lowcost processing, and compatibility with large-area fabrication. However, their efficiency is hindered by interfacial defects and vertical phase separation in the active layer, which induce charge imbalance and recombination losses. This work presents an interfacial engineering approach to overcome these limitations in P3HT:PC₇₀BM-based OPVs. Two key strategies were employed: (i) reducing the post-deposition annealing time of the active layer to suppress PC₇₀BM accumulation at the bottom electrode, and (ii) using a DCB:DCM mixed solvent system to regulate solvent evaporation, thereby promoting uniform film formation during PC₇₀BM overlay deposition. Devices fabricated with these optimizations exhibited notable enhancements, achieving short-circuit current density up to 15.83 mA/cm² and a 58.1% increase in power conversion efficiency compared to control devices. X-ray photoelectron spectroscopy confirmed reduced surface aggregation of PC₇₀BM, while X-ray diffraction indicated improved P3HT crystallinity and molecular ordering. These results highlight the critical role of interfacial and morphological control in enhancing charge separation and transport, offering a practical route toward efficient, reproducible, and stable OPVs.

To ensure the long-term reliability of flexible photovoltaic (FPV) modules, it is crucial to develop an effective moisture barrier layer that prevents the infiltration of moisture and oxygen. We developed such a layer composed of parylene (700 nm) and AlOx (70 nm), optimizing its material properties, moisture-blocking performance, and processing conditions. The barrier layer applied to the Ethylene Tetrafluoroethylene (ETFE) substrate demonstrated a water vapor transmission rate (WVTR) of 6.33 × 10^-2 g/m²/day and an average visible light transmittance (AVT) of 85.3% over the 380-780 nm wavelength range. For the FPV module with this barrier, Damp/Heat (DH) reliability testing was conducted at 85℃ and 85% relative humidity for up to 1,000 hours. During testing, the power conversion efficiency (PCE) decreased slightly from 25.4% (0 hr) to 24.7% (1,000 hr), reflecting a minimal reduction of only 0.7%. The primary cause of degradation was identified as a -4% relative change in shortcircuit current density (JSC) before and after DH testing. Consequently, the ETFE/parylene/AlOx multilayer moisture barrier proved highly effective in ensuring the long-term reliability of solar modules.

The printed and bifacial organic photovoltaics (OPVs) using a semi-transparent electrode structure to enhance light management were investigated. To optimize energy-band alignment for bifacial device structure, a cathode interlayer of ZnO nanoparticles with a low work function of 3.9 eV combined with a polyethyleneimine (PEI) layer was employed. Photon distribution simulations revealed the influence of structural parameters on device conductivity, light absorption, and surface morphology. The dispensing strength, adjusted via applied voltage during printing, significantly impacted device performance. At 13 V and 17 V, J-V characteristics were consistent; however, at 20 V, line width increased by approximately 100%, resulting in a 50% reduction in PCE. These findings highlight the critical relationship between spraying strength, line width, and efficiency, offering valuable insights for advancing printed OPV technologies.

MBB (multi-busbar) technology is a module technology to achieve high power, and the use of a number of thin circular metal wires increases light-receiving capacity and reduces resistance. In the process of interconnection using a wire, the stress of the cell increases depending on the degree of coupling between the wire and the cell and the degree of damage caused by heat, or the mobility of current decreases due to poor bonding. The degree of such loss is affected by IR lamp, hot plate temperature and wire thickness. In addition, the values of contact resistance were compared and analyzed to analyze the cause of the decrease in electrical characteristics. In this study, process condition optimization was carried out through peeling test, SEM analysis, EL test, and pre/post bonding efficiency characteristic analysis of the bonded cell according to process conditions, compared the contact resistance.

The possibility of a dye-sensitized solar cell (DSSC) submodule was evaluated as an independent power source that can drive a smart liquid crystal window (SLW) that selectively blocks sunlight when electricity is applied. In order to save energy and increase the functionality of buildings, SLW operation was supplied directly from DSSC submodule, rather than connecting to the existing power system and external power sources. It was confirmed that the SLW can control light transmittance through self-generation using the DSSC submodule composed of 6 cells at low light of 2,500 lux. These results imply that there is a high possibility of combining smart windows and DSSCs suitable for window-type building-integrated photovoltaic (BIPV) systems. DSSCs, which can self-generate power in low light, are expected to increase their usability in urban BIPV systems through combination with smart window technology.

Organic photovoltaic (OPV) devices have attracted attention due to their high efficiency and simple manufacturing process. Applying an overlayer to OPV devices is one way to improve their performance because it can improve charge extraction and suppress vertical phase separation. In addition, dichloromethane (DCM) was used as an orthogonal solvent to minimize the effect on other layers. However, an coating problems due to the use of DCM were found, which affects surface morphology as rough or peeling. Additional research efforts are needed to solve these problems, and optimal results are expected to be obtained by utilizing various buffer layers or selective organic solvents.

The energy demand in the world is expected to exceed 740 million TJ by 2040 and our dependence on fossil fuels needs to be switched to sustainable and renewable energy sources like solar energy. Building Integrated Photovoltaic (BIPV) is one of the best approaches to extracting solar energy. There are more than 200 BIPV products in the market currently but when it comes to integrating these products into the technical aspects such as buildings’ structural integrity, thermal, daylight retainment and aesthetic prospects to be considered. The share of BIPV integration potential of different building types in the world of residential, agricultural, industrial, commercial and other buildings account for 66%, 4.8%, 8.1%, 19.9%, and 1.2% accordingly. Many solar technologies developed to achieve architectural requirements, but the main problem is the trade-off between efficiency and aesthetic appeal, which is less than 10% in coloured and transparent solar modules. This paper discusses the different applications of solar photovoltaics (PV) in building architecture, technical requirements, and different module technologies. The article provides a comprehensive guide for researchers and designers working on the development of BIPV integrations.

Aluminum-induced crystallization (AIC) as a route to reduce the fabrication cost and to obtain polycrystalline Si (p- Si) thin-film of large grain size is a promising alternative of single-crystalline (s-Si) substrate or p-Si thin-film obtained by conventional methods such as solid phase crystallization (SPC) and laser-induced crystallization (LIC). As the AIC process occurs at the interface between a-Si and Al thin-films, there are various process and interface parameters. Also, it directly means that there is a certain parametric window to obtain p-Si of large grain size having uniform crystal orientation. In this article, we investigate the effect of the various process and interface parameters to obtain p-Si of large grain size and uniform crystal orientation from the literature review. We also suggest the potential use of the p-Si as a virtual substrate for the growth of various compound semiconductors in a form of low-dimension as well as thin-film as a way for their monolithic integration on Si.

We have studied the effects of Ag on the characteristics of Sn₄₈In₅₂Ag_x (wt%) low-melting solders for photovoltaic ribbons. The Sn₄₈In₅₂ (wt%) solder coexisted in the InSn₄ and In₃Sn alloys. Ag atoms added in the solder formed an AgIn₂ alloy by reacting with some part of In atoms, while they did not react with Sn atoms. The addition of Ag atoms in the Sn₄₈In52Agx (wt%) solders showed useful results; an increase in peel strength and a decrease in melting temperature. The peel strength of the ribbon plated with the Sn⁴⁸In⁵² (wt%) solder was 53.6 N/mm², and that of the Sn⁴⁸In⁵²Ag1 (wt%) solder largely increased to 125.1 N/mm². In the meanwhile, the melting temperature of the Sn₄₈In⁵² (wt%) solder was 119.2℃, and that of the Sn48In52Ag1 (wt%) solder decreased to 114.0℃.

In this paper, we analyzed the transformation of the power following by the angle of incidence of the solar, the angle of photovoltaic module and artificial solar changed from 30° to 90° and synchronously changed the distance from 0.1 m to 0.5 m. Setting the distance between the artificial solar and the luminometer from 0.1 m to 0.5 m and set the angles to 90°, 60°, 45°, and 30°, the angle was 90° and when the distance was 0.1 m, the maximum Illuminance was 19,580 lux, the light could be obtained more. If the angle of incidence between the Artificial solar and the photovoltaic module was 90° and the variable resistance was 1,000 Ω at a distance of 0.4 m, the maximum power reached 0.82 W. Provided that the angle of incidence between the artificial solar and the photovoltaic module was 90° and the distance was 0.2 m since the variable resistance had the maximum power of 500 Ω, the maximum power was 0.78 W. At 1,000 Ω, the maximum power is 0.80 W so the maximum power at the variable resistance 1,000 Ω could obtain higher power than the variable resistance 500 Ω. The variable resistance was 1,000 Ω and the angle of incidence between the Artificial solar and the photovoltaic module was 90° at a distance of 0.4 m, and the maximum power reached 0.82 W. The angle was 60° at 0.3 m and 0.4 m the maximum power reached 0.10 W. The angle was 45° at 0.2 m maximum power reached 0.020 W, the angle was 30° at 0.4 m, and the maximum power reached 0.004 W. In four results about maximum power depending on the angle of incidence between the artificial solar and the photovoltaic module, the luminous efficiency and maximum power can be got the best at an angle of 90°.

We studied the various characteristics of Sn-In (wt%) Pb-free solders for photovoltaic ribbon application. The solders near the eutectic composition of Sn₄₈In₅₂ (wt%) existed in InSn₄ and In₃Sn alloy phases, and in In crystal phase, but not in Sn crystal phase. In addition, the InSn4 phase (γ-alloy) existed separately from the In₃Sn (β-alloy) and the In phase confirmed by an SEM-EDS-mapping. The melting temperature of the eutectic solder of Sn₄₈In₅₂ (wt%) was 119.2℃, and when the Sn content decreased in reference to the eutectic composition, it slightly increased to 121.4℃, but when the Sn content increased, it remained almost constant at 119.1℃. The peel strength of the ribbon plated with the Sn₄₂In₅₈ (wt%) solder was 38.7 N/㎟, and it tended to increase when the Sn content increased. The peel strength of the eutectic Sn₄₈In₅₂ (wt%) solder was 53.6 N/㎟, and that of the Sn₅₁In₄₉ (wt%) solder was 61.6 N/㎟ that was the highest.

As the demand for new and renewable energy increases due to the depletion of fossil fuels, solar power generation, a core energy source for new and renewable energy, requires research on solar modules for high output power generation. In this paper, the electrical characteristics of solar cell strip at the edge and in the center of single-crystal silicon having a semi-square shape were analyzed. The cell strip located in the center showed the efficiency increase by 0.26% compared to the cell strip at the edge of the solar cell. A shingled photovoltaic module was manufactured for each cell strip. As a result, the output power of the module using the cell strip located in the center was higher by 0.992%.

For the last decades, a research hotspot for the halide perovskites (HPs) is now showing great progress in terms of improving efficiency for numerous photovoltaic devices (PVDs). However, it still faces challenges in the case of long-term stability in the air atmosphere. Defect-free high-quality HP single crystals show their promising properties for the remarkable development of highly efficient and stable PVDs. Here, we summarize the growth processing routes for the stable HP single crystals as well as briefly discuss the pros and cons of those well-established synthesis routes. Furthermore, we briefly include the comparison note between the HP single crystals and polycrystalline perovskite films regarding their device applications. Based on the future progress, the review concludes subjective perspectives and current challenges for the development of HPs high-quality PVDs.

In this study, we fabricated light-weight solar module for various applications such as building integrated photovoltaics (BIPV), vehicles, trains, etc. Ethylene tetra fluoro ethylene (ETFE) film was applied as a material to replace the cover glass, which occupies more than 65% of the weight of the PV module. Glass fiber reinforced plastic (GRP) was applied to the ones with a low durability by replacing the cover glass to ETFE. Moreover, to achieve a high solar power conversion in this study, we applied a shingled design to weight reduced solar modules. The shingled module with GRP shows 183.7 W of solar-to-power conversion, and the output reduction rate after weight load test was 1.14%.

An increase in the temperature of photovoltaic (PV) modules causes reduced power output and shorter lifetime. Because of these characteristics, demands for the heat dissipation of PV modules are increasing. In this study, we attached a heat dissipation sheet to the back sheet of a shingled PV module and observed the temperature changes. The PV shingled module was tested under Standard Test Conditions (STCs; irradiance: 1,000 W/m², temperature: 25℃, air mass: 1.5) using a solar radiation tester, wherein the temperature of the PV module was measured by irradiating light for a certain duration. As a result, the temperature of the PV module with the heat dissipation sheet decreased by 3℃ compared to that without a heat dissipation sheet. This indicated that the power loss was caused by a temperature increase of the PV module. In addition, it was confirmed that the primary parameter contributing to the reduced PV module output power was the open circuit voltage (Voc).

A coverglass pattern was designed to improve the annual electrical energy production of a building-integrated photovoltaic (BIPV) module installed in the exterior walls of buildings. The transmittance pattern was calculated using ray tracing, and the results were derived by optimizing the simulation using Taguchi’s method. We obtained the optimal pattern by analyzing the conventional patterns for improving the transmittance and derived design factors by quantifying the pattern. By calculating the influence of electrical energy on each design factor, we obtained the optimal coverglass pattern that produced the maximum annual electrical energy. The annual electrical energy production improved by approximately 11.79% compared to the non-patterned coverglass.

The high power of a shingled photovoltaic module can be attributed to its low cell-to-module loss. The production of high power modules in limited area requires high efficiency solar cells. Shingled photovoltaic modules can be made by divided solar cells, which can be produced by the laser scribing process. After dividing the 21% PERC cell using laser scribing, the efficiency decreased by approximately 0.35%. However, there was no change in the efficiency of the solar cell having relatively lower efficiency, because the laser scribing process induce higher heat damages in solar cells with high efficiency. To prove this phenomena, the J₀ (leakage current density) of each cell was analyzed. It was found that the J₀ of 21% PERC increased about 17 times between full and divided solar cell. However, the J₀ of 20.2% PERC increased only about 2.5 times between full and divided solar cell.

Recently, with the increase in the use of urban solar power, solar modules are required to produce high power in limited areas. In this report, we proposed the fabrication of a high-power photovoltaic module using shingles technology, and developed accurate string characteristic simulations based on circuit modeling. By comparing the resistance components between the interconnected cells and the cell strips, the ECA resistance was determined to be 0.003 Ω. Based on the equivalent circuit of the modeled shingled string, string simulation was performed according to the type of cell strip. As a result, it was determined that the cell efficiency of the 4-cell strip was the highest at 19.66%, but the efficiency of the string simulated with the 6-cell strip was the highest at 20.48% in the string unit.

Advances in laser technology have enabled ultra-high-speed ultra-precise processing, thus expanding potential applications to the semiconductor, medical, and photovoltaic industries. In particular, laser scribing technology has been applied to the production of shingled solar modules. In this work, we analyze the effect of laser scribing conditions, e.g., scribing depth, on the characteristics of the resulting divided solar cells. When the scribing depth was greater than 100 ㎛, the solar cells were well separated. In addition, the desired scribing depths were reached in fewer scans when the laser spot overlap was 100%. The efficiency of the divided cells decreased due to the high series resistance at scribing depths of less than 100 ㎛. However, at scribing depths of approximately 100 ㎛, the series resistance was low and efficiency reduction was minimized.

In our study, we collected data from a 100 kW floating photovoltaic (PV) system installed in Gyeongnam Hapcheon Dam and observed correlations between the power generation of the floating PV system and the irradiance, water temperature, humidity, ambient temperature, wind speed, and module temperature. Firstly, there was little correlation between the water temperature and power generation. Secondly, the ambient temperature, wind speed, and humidity all showed greater correlations with power generation. Finally, the power generation was very highly correlated with the irradiance and module temperature. In conclusion, the power generation of the floating PV system is related individually to environmental factors.

Ultraviolet (UV) photodetectors are used in various industries and fields of research, including optical communication, flame sensing, missile plume detection, astronomical studies, biological sensors, and environmental research. However, general UV detectors that employ Schottky junction diodes and p^-n junctions have high fabrication cost and low quantum efficiency. In this study, we investigated the characteristics of materials used to manufacture UV photodetectors in a low-cost solution process that requires easy fabrication of flexible substrates. We fabricated p-type NiO and n-type ZnO substrates with wide band gap by the sol^-gel method and compared the characteristics of substrates prepared under different spin-coating and heat-treatment conditions.

Because silicon thin film solar cells have a high absorption coefficient in visible light, they can absorb 90% of the solar spectrum in a 1-μm-thick layer. Silicon thin film solar cells also have high transparency and are lightweight. Therefore, they can be used for building integrated photovoltaic (BIPV) systems. However, the contact electrode needs to be replaced for fabricating silicon thin film solar cells in BIPV systems, because most of the silicon thin film solar cells use metal electrodes that have a high reflectivity and low transmittance. In this study, we replace the conventional aluminum top electrode with a transparent aluminum-doped zinc oxide (AZO) electrode, the band level of which matches well with that of the intrinsic layer of the silicon thin film solar cell and has high transmittance. We show that the AZO effectively replaces the top metal electrode and the bottom fluorine-doped tin oxide (FTO) substrate without a noticeable degradation of the photovoltaic characteristics.

In this paper, the effects of environmental variables on the output of the floating photovoltaic water systems, which were installed at the Hapcheon dam in South Korea, were investigated, and the correlations between them were analyzed. The system output was linearly proportional to the solar radiation or irradiance. The output was large in spring and autumn because of high irradiance, but low in the summer when the solar module temperature was high. The influence of the module temperature on the system output was limited in the summer, during which the module temperature change affected the system output more than the change of the irradiance did. In addition, in winter and summer, the module temperature tended to decrease with increasing windspeed, but windspeed did not affect module temperature significantly in the spring and autumn. On the other hand, in winter and spring, the irradiance decreased as the windspeed increased because of movement (or circulation) of the photovoltaic modules.

We have studied the effects of Ag on the characteristics of Sn₄₃Bi₅₇Ag_x(wt%) lead-free solders for photovoltaic ribbon. Ag atoms in the solder formed an alloy phase of Ag₃Sn after reacting with some part of Sn atoms, while they did not react with Bi atoms, but decreased the mean size of Bi solid phase and the thickness of solder. When Ag atoms of 3.0 wt% was added to eutectic Sn₄₃Bi₅₇(wt%) solder, it showed the optimally useful results that the peel strength of photovoltaic ribbon greatly increased and the sheet resistance of the solder decreased. In the meanwhile, the eutectic Sn₄₃Bi₅₇(wt%) solder showed a low melting temperature of 138.9℃, and showed a very similar result regardless of the added amount of Ag atoms.

Among several types of energy saving smart window technologies, the leader, the dynamic EC (electrochromic) window one needs integrated PV (photovoltaics), to minimize expensive electrical wiring as well as to obviate the need for external energy. Self-powered smart windows were reviewed according to PV types used. DSSCs (dye sensitized solar cells) were found to be compatible with EC cells, to have several categories of next generation smart windows such as PECCs (photoelectrochromic cells), PVCCs (photovoltachromic cells), EC polymer PECCs. In addition silicon solar cells and third generation solar cells were investigated. They are summarized in a table showing their advantages and disadvantages respectively for a fast comparison. The strategy to expedite the commercialization of these next generation smart windows includes developing retrofit smart window coverings for use on flexible polymer substrates adhered to the inside surface of a window and easily replaced after use for upto 10 years.

In this paper, the power generation efficiency of the 4 [kW] fixed-concentrated type photovoltaic power generation system and that of the 4 [kW] single axis trace type photovoltaic power generation system were compared. For that purpose, the two types of photovoltaic power generation systems have been in operation for 1year on an experimental basis. The amounts of power generated by the two types during the months of January through December and the characteristics of their operating times during the same period have been compared and analyzed. For the study, the type with higher efficiency was selected and the following conclusions have been reached. It was shown that the amount of power generated and the average operation times during the spring months of March through May are higher that those of the summer months of June through August when more sunlight is available. The reason for this phenomenon is thought to be that as the temperatures of the solar panel surface and the surrounding environment go up, the electric current decreases.

We have studied the effects of Ag on the characteristics of Sn60Pb40Agx (wt%) solder for photovoltaic ribbon. Ag atoms in the solder formed an alloy phase of Ag3Sn after reacting with some part of Sn atoms, while they did not react with Pb atoms, but decreased the mean size of Pb solid phase. The enhancement of peel strength between solar cell and ribbon is an important part in the developments of long-lifespan solar module. The peel strength of the solder ribbon of Sn60Pb40 (wt%) was 169 N/mm2, and it was largely enhanced by adding a small amount of Ag atoms. The maximum peel strength was 295 N/mm2 in the solder ribbon of Sn60Pb40Ag2 (wt%). This result is caused by the high binding energy of 162.9 kJ/mol between Ag atoms in the solder and Ag atoms in Ag sheet.

In this paper existing buildings, not a new buildings and house for living people not just a displaying and a viewing, created by the imagine effect or virtual simulation was applied various Active and Passive elements. After constructing zero-energy houses, through default case happened during operation period it is described problems and solutions about field part, work classification, installation by Location part, and Installation equipment part. Since then, to take advantage of this thesis, it``s the purpose of this paper using as the baseline data for building a zero-energy house in another similar case.

Dye-sensitized solar cells (DSSCs) based on titanium dioxide (TiO2) have been extensively studied because of their promising low-cost alternatives to conventional semiconductor based solar cells. DSSCs consist of molecular dye at the interface between a liquid electrolyte and a mesoporous wide-bandgap semiconductor oxide. Most efforts for high conversion efficiencies have focused on dye and liquid electrolytes. However, interface engineering between dye and electrode is also important to reduce recombination and improve efficiency. In this work, for interface engineering, we deposited semiconducting ferroelectric BiFeO3 with bandgap of 2.8 eV on TiO2 nanoparticles and nanotubes. Photovoltaic properties of DSSCs were characterized as a function of thickness of BiFeO3. We showed that ferroelectric BiFeO3-coated TiO2 electrodes enable to increase overall efficiency of DSSCs, which was associated with efficient electron transport due to internal electric field originating from electric polarization. It was suggested that engineering the dye-TiO2 interface using ferroelectric materials as inorganic modifiers can be key parameter for enhanced photovoltaic performance of the cell.