Views: 0 Author: Site Editor Publish Time: 2026-07-31 Origin: Site
Against the background of the global dual-carbon goal advancement and the construction of new power systems, photovoltaic power generation has become the fastest-growing renewable energy power generation technology in the world by virtue of its advantages of clean and low-carbon attributes, extensive resources and strong adaptability. As the core carrier of photovoltaic power generation systems, photovoltaic modules undertake the core function of directly converting solar energy into electrical energy. Their conversion efficiency, service life, stability and environmental adaptability directly determine the power generation capacity, operation and maintenance cost and full-life-cycle benefits of photovoltaic power generation systems.
After decades of technological iteration, the photovoltaic industry has evolved from early low-efficiency polycrystalline technology to a technological pattern dominated by high-efficiency N-type crystalline silicon cells and frontier perovskite tandem cells. The continuous breakthroughs in conversion efficiency of commercial modules, optimization of attenuation performance and improvement of scenario adaptability have greatly reduced the levelized cost of electricity (LCOE) of photovoltaic power generation, realizing the transformation of photovoltaic power from supplementary energy to mainstay energy. Based on the latest technological achievements of the photovoltaic industry, this paper conducts a systematic professional analysis from six dimensions: core principles, technical routes, structural processes, performance management and control, operation and maintenance diagnosis, and frontier trends.
The core energy conversion mechanism of photovoltaic modules is thephotovoltaic effect, which essentially refers to the photo-induced carrier excitation and directional migration process of semiconductor materials under illumination. Crystalline silicon, the core material of photovoltaic cells, has a fixed band gap in its band structure, which can accurately absorb photon energy in the visible and near-infrared bands of sunlight to realize photoelectric conversion.
The specific working mechanism consists of four core stages. First, photon excitation: when solar photons irradiate the cell surface, photons with energy higher than the band gap energy of silicon break the valence electron bondage of silicon atoms and excite electron-hole pairs. Second, carrier separation: the built-in electric field formed by the PN junction rapidly separates electrons and holes, with electrons migrating to the N-type region and holes to the P-type region, realizing the directional separation of positive and negative charges. Third, charge accumulation: charges continuously accumulate at both poles of the cell to form a stable photoelectromotive force. Fourth, power output: a closed loop is formed through the metal grid lines, solder ribbons and external circuits of the module, and the directional migration of carriers generates continuous current, ultimately converting solar energy into available DC power.
Single photovoltaic cells have limited output voltage and current. In industrial production, multiple cells are connected in series and parallel and packaged into photovoltaic modules. Matched with packaging adhesive films, tempered glass, backsheets and other structures, the cells are protected with stable performance to adapt to long-term and complex outdoor operating conditions.
Currently, crystalline silicon cells dominate the industrialized photovoltaic module market, accounting for more than 95% of the global market share, which is divided into two major technical systems: P-type and N-type. Meanwhile, perovskite and tandem cells, as a new generation of cutting-edge technologies, have entered the industrial pilot stage, with significant differences in performance, technology and application scenarios among various technical routes.
PERC (Passivated Emitter and Rear Contact) technology is the core iteration of P-type cells. By adding an aluminum oxide passivation layer and a silicon nitride protective layer on the rear side of cells, it effectively reduces the carrier recombination loss on the cell rear surface and improves light absorption efficiency and photoelectric conversion efficiency. At present, the conversion efficiency of commercial PERC modules is stably maintained at 22.5%–23.5%, which is close to the theoretical efficiency limit of 24.5% for P-type silicon cells, leaving limited room for technological improvement.
With mature processes, complete industrial chain supporting facilities and low manufacturing costs, PERC technology has been the mainstream choice for photovoltaic power stations in the past. However, it has inherent drawbacks: high light attenuation rate with an initial annual attenuation of about 2.0% and a steady annual attenuation of approximately 0.45% in subsequent years; it also suffers from light-induced attenuation and electricity-induced attenuation, with mediocre power generation performance under high temperature and weak light conditions, thus being gradually replaced by N-type technologies. At this stage, the industry mainly taps residual efficiency potential through black silicon texture optimization, multi-busbar (SMBB) metallization process and passivation layer iteration.
TOPCon (Tunnel Oxide Passivated Contact) is the core mainstream technology of current N-type cells and has become the core expansion direction of the industry due to its excellent performance advantages. This technology prepares an ultra-thin silicon oxide tunneling layer and a doped polysilicon layer on the cell rear side to form a passivated contact structure, which significantly reduces the surface recombination rate of cells and improves open-circuit voltage and fill factor.
Compared with PERC technology, TOPCon modules have prominent core advantages: the commercial conversion efficiency reaches 25%–26% with a higher efficiency ceiling; the attenuation performance is greatly optimized, with the first-year attenuation ≤1% and a steady annual attenuation of only 0.3%, delivering outstanding full-life-cycle power generation gains; it has superior weak light response, high temperature adaptability and shading resistance, suitable for complex scenarios such as mountainous areas, residential and industrial and commercial rooftops. In addition, this technology is compatible with most existing PERC production line equipment with high renovation cost performance, achieving the fastest industrialization and becoming the preferred technical route for new photovoltaic projects.
Tandem cell technology is a cutting-edge core technology to break the band gap limitation of single crystalline silicon and overcome the photoelectric conversion efficiency limit. Its core principle is to vertically stack sub-cells with different band gaps to absorb different spectral bands of sunlight respectively, maximizing the utilization of solar spectrum resources. Among them, crystalline silicon-perovskite tandem and perovskite-organic tandem technologies have achieved the most prominent progress.
Perovskite materials have the advantages of adjustable band gap, high light absorption coefficient, flexible preparation and low-cost mass production, forming a perfect complement to crystalline silicon cells. The steady-state certified efficiency of domestically developed perovskite-organic tandem solar cells reaches 28.04%, while the small-area device efficiency of ultra-thin crystalline silicon-perovskite tandem cells is certified by NREL at 33.4%, setting a new world record. Tandem cells integrate high efficiency, light weight and flexible adaptability, which are not only applicable to large-scale ground photovoltaic power stations, but also suitable for emerging scenarios such as building-integrated photovoltaics (BIPV), vehicle-mounted photovoltaics and portable power generation, serving as the core iterative direction of future photovoltaic technology.
The packaging structure and manufacturing process of photovoltaic modules directly determine their outdoor stability, power generation efficiency and service life. The industry has achieved all-round improvements in module power density, reliability and durability through continuous structural innovation and process upgrading. The standard photovoltaic module structure consists of tempered glass, packaging adhesive film, cells, backsheet, frame and junction box from outside to inside, and each structure cooperates to realize functions such as light transmission and power generation, insulation protection, waterproof and moistureproof performance, and mechanical compression resistance.
Current mainstream process upgrades focus on four major directions. First, zero-gap cell arrangement technology eliminates the traditional gap design between cells, maximizes the effective light-receiving area of modules, and improves the overall power generation without changing module dimensions. Second, integrated conductive backsheet technology cancels the traditional ribbon series structure, adopts a full-area contact conductive mode, reduces solder joint risks, lowers hidden crack, desoldering and transmission loss, relieves module stress, and improves waterproof performance and attenuation resistance. Third, multi-busbar and fine grid metallization technology reduces the shading area of grid lines, improves current transmission efficiency, and adapts to the power generation needs of high-efficiency cells. Fourth, new passivation and protection technologies adopt nano-layered structures, indium cerium oxide thin films and other new materials to enhance the weather resistance, aging resistance and shading resistance of modules and extend the full life cycle.
In addition, the built-in bypass diode structural design has become the standard configuration of new modules. It can quickly conduct the bypass channel when modules are partially shaded, avoiding hot spot effect damage to cells and significantly improving the power generation stability and service life of modules under complex working conditions.
The actual power generation performance of photovoltaic modules is not constant. Affected by environmental conditions, material characteristics, process defects and other factors, continuous attenuation and dynamic fluctuations occur. Clarifying its influence mechanism is the core of module performance management and service life prediction.
Solar irradiance is the core factor determining module power generation, and the power generation is basically linearly positively correlated with irradiance. Ambient temperature directly affects conversion efficiency. Crystalline silicon cells have a negative temperature coefficient; every 1 ℃ increase in temperature reduces the conversion efficiency by 0.3%–0.4%, and high temperature significantly reduces module output performance. Wind sand, rain, snow and dust shading reduce the light-receiving area, causing hot spots, local reverse bias and other problems and resulting in power loss. High humidity, salt spray and ultraviolet radiation accelerate the aging of packaging materials, causing adhesive film yellowing, backsheet cracking, insulation failure and other faults.
The full-life-cycle attenuation of photovoltaic modules is mainly divided into three categories. First, initial light-induced attenuation: P-type cells generally have carrier activation defects in the early stage of illumination, leading to significant power attenuation in the first year, while N-type TOPCon cells have basically no obvious light-induced attenuation. Second, steady-state annual attenuation: it is caused by the accumulation of material aging and carrier recombination loss, which is the main cause of long-term performance degradation of modules. Third, stress-induced attenuation: mechanical load, thermal cycling, local shading, electrical stress and other factors cause cell hidden cracks, ribbon falling off, bypass diode failure and other irreversible power loss.
For new technologies such as perovskite cells, halogen phase separation is the core attenuation inducement. Under illumination stress, iodide ions and bromide ions in perovskite thin films redistribute to form iodine-rich and bromine-rich regions, which greatly reduce the output voltage and long-term stability of devices, and also serve as a key technical bottleneck to be broken through in the industrialization of cutting-edge technologies.
Photovoltaic modules are prone to various faults during long-term outdoor operation, which can be divided into module body faults and inter-module matching faults. Body faults include cell hidden cracks, hot spots, packaging aging, bypass diode failure, etc. Inter-module faults mainly include series-parallel mismatch, shading loss and poor line contact. Accurate diagnosis and efficient operation and maintenance are the keys to improving power station power generation efficiency and reducing operation and maintenance costs.
The industry has formed an intelligent and accurate fault diagnosis system. Based on the single-diode equivalent circuit model of photovoltaic modules, it can analyze the changes of electrical parameters under different irradiance and temperature conditions and realize fault mechanism traceability. Artificial intelligence diagnosis models such as improved sparrow search algorithm and random forest algorithm can significantly improve the fault recognition accuracy of photovoltaic arrays and realize accurate fault classification under multiple working conditions. Combined with infrared temperature measurement, EL electroluminescence detection, UAV inspection and other technologies, visual detection of module hidden cracks, hot spots, aging and other defects can be realized, adapting to the operation and maintenance needs of large-scale photovoltaic power stations.
Regular operation and maintenance management can effectively delay module attenuation and reduce fault probability. The core operation and maintenance measures include regular cleaning and dust removal, electrical parameter detection, screening and replacement of faulty modules, and insulation detection of junction boxes and lines. Full-life-cycle operation and maintenance can effectively improve the overall power generation revenue of power stations.
Combined with the current progress of technological research and development and industrialization, future photovoltaic modules will iterate towards six major directions: high efficiency, low attenuation, light weight, flexibility, intelligence and low cost.
First, N-type technology will fully replace P-type technology. TOPCon cells will be continuously iterated and optimized through the upgrading of passivation and metallization processes to further improve conversion efficiency and reduce attenuation rate, becoming the mainstream industrial technology in the next 3–5 years, while PERC technology will gradually withdraw from the new market.
Second, tandem cells will accelerate industrialization. With ultra-high efficiency advantages, crystalline silicon-perovskite and perovskite-organic tandem cells will realize small-batch mass production gradually. After solving technical bottlenecks such as halogen phase separation and long-term stability, they will open a new era of high-efficiency photovoltaic technology and break the efficiency ceiling of single crystalline silicon cells.
Third, lightweight and flexible upgrading. New perovskite and thin-film photovoltaic modules can be prepared flexibly, breaking the morphological limitations of traditional rigid crystalline silicon modules, adapting to emerging scenarios such as building-integrated photovoltaics, mobile energy and outdoor portable power generation, and expanding the boundary of photovoltaic applications.
Fourth, continuous optimization of structure and technology. Advanced processes such as zero-gap arrangement, integrated conduction and intelligent bypass protection will be fully popularized, continuously improving module power density, attenuation resistance, shading resistance and weather resistance, and reducing the full-life-cycle levelized cost of electricity.
Fifth, in-depth integration of intelligent operation and maintenance. Artificial intelligence fault diagnosis, UAV intelligent inspection, digital twin management and other technologies will be fully applied to realize fault prediction, performance monitoring and intelligent operation and maintenance of photovoltaic modules, and improve the intelligent operation level of photovoltaic power stations.
The continuous iteration of photovoltaic module technology is the core support for the high-quality development of the photovoltaic industry. From the industrial upgrading of traditional P-type PERC to N-type TOPCon, to the breakthrough of tandem cell frontier technologies, the industry has achieved all-round leaps in photoelectric conversion efficiency, stability and scenario adaptability. At present, high-efficiency N-type crystalline silicon modules have become the market mainstream, greatly improving the economy and reliability of photovoltaic power generation. The breakthrough of new technologies such as tandem photovoltaic and flexible photovoltaic provides broad space for the long-term development of the photovoltaic industry.
In the future, with the continuous innovation of material science, packaging technology and intelligent operation and maintenance technology, photovoltaic modules will further break through efficiency and cost bottlenecks, adapt to more complex application scenarios, continuously consolidate the main energy position of photovoltaic power generation in new power systems, and provide solid technical support for global energy transformation and the implementation of dual-carbon goals.
