In recent years, countries all over the world have invested heavily in the research of solar energy application technology and have made great technical progress. Since the 1990s, with the increase in the cost of conventional power generation methods and people’s increasing emphasis on environmental protection, “building production sources†and “household grid-connected photovoltaic systems†are the goals pursued by the photovoltaic industry. Since then, some experts have proposed some solutions for the organic integration of the tourist curtain wall and the photovoltaic grid-connected system, aiming to jointly improve the application technology of photovoltaic modules in the curtain wall BIPV (Integrated Photovoltaic Building).
The term “photovoltaic building integration†first originated in foreign countries. Its solar energy utilization technology has profound historical and technological foundations, and is particularly prominent in photovoltaic building integration. It is commonly used for curtain wall building structures, such as a curtain wall that is more famous in Germany. The company has already installed double-glass photovoltaic modules directly on the external wall of the curtain wall. There are many architectural shapes that give people a new look. The practice they adopted can not only ensure the safety performance of the building's curtain wall, but also enable the use of solar energy sources. It is a green energy construction.
Photovoltaic modules produced in China account for a large share of the world. There are also examples of photovoltaic power stations in China. However, the demonstration projects that can truly match the foreign-made photovoltaic building integration are rare. There are two reasons for this. First, the production companies of photovoltaic modules and photovoltaic systems lack the technology in the design of curtain wall construction. Little is known about the installation requirements of curtain walls. Second, as a curtain wall company, their application concepts for photovoltaic power generation are rather vague, and no deeper research has been conducted. For these two reasons, there are no good example projects in China that can be shared by industry peers.
In the design of photovoltaic building integration, the latitude and longitude of the location where the building is located is usually combined with the local weather release to find the best angle of the solar power generation. The square array of general solar photovoltaic systems is installed in the south, and its solar energy has the highest collection of energy. When the photovoltaic curtain wall is designed, the wind pressure, seismic resistance, elevation of the wind load, and sealing performance must also be considered. The proper installation angle and direction should be selected. The photovoltaic ceiling lighting roof is the best installation structure.
In the application of photovoltaic building integration, the influence of rainy days on the indoor side light should also be considered. The light transmittance of the module can be designed to be in the range of 10% to 50%, and the proper light transmittance can be achieved by the arrangement interval of the crystalline silicon cells in the module. In some cases, amorphous silicon can also be used to process building components. This requires consideration of whether the safety performance of the components meets the design requirements for the part of the building's curtain wall. Photovoltaic lighting roof adopts horizontal and vertical structure, which is more convenient for roof drainage. Since photovoltaic curtain walls are a form of expression in special buildings, it is necessary to consider the practical problems of ventilation and cooling. At the time of design, the external decoration and the curtain wall structure were coordinated and integrated to make the photovoltaic building integrated with more vitality and reflect the environmental protection green design concept of modern architecture.
The photovoltaic curtain wall itself has a building code that complies with the curtain wall, and can use solar energy to convert sunlight into DC electrical energy, transform it into an AC power supply through an inverter, or commutate and regulate DC power through a controller. Its power generation system includes independent grid systems, grid-connected systems, and independent grid systems with energy storage. It is rationally designed and deployed in the integration of photovoltaic buildings. Due to the battery life and maintenance issues, grid-connected systems are often used to provide more advantages for photovoltaic curtain walls. The construction cost of grid-connected systems is lower than that of independent grid systems with energy storage, and the annual power generation of grid-connected systems is higher than that of independent grids. More systems. The independent grid system with energy storage has an emergency power generation function. This is the advantages and disadvantages of the two.
When designing the system, taking into account the fact that safety and sealing performance are easy to maintain, designing the double glass PV module as a hidden frame type is a better combination. Lead the assembly lead from the edge of the assembly through the customized lead box to the positive and negative poles and configure the quick connect plug. The serial and parallel cables of the component are routed from the outer side or the upper and lower side slots of the aluminum profile of the hidden frame structure curtain wall and are integrated into the wiring junction box of each unit, supporting bypass diodes and anti-recharge diodes, and finally the summary of each bus box. To DC cabinets to complete the DC input. After the connection is completed, the gusset plate is covered and the edge of the sealant is used for concealed installation. This will not only ensure the sealing of the components to achieve the corresponding waterproof requirements, but also does not affect the visual appearance of the curtain wall roof, which is a relatively perfect combination of structures.
Solar energy is the most widely distributed renewable energy resource in China. It can use remote land resources, and can also use large amounts of roof and wall resources to effectively increase energy supply. Photovoltaic power generation does not consume fossil energy resources and water resources, does not generate pollution, and does not generate greenhouse gas emissions. It is not only suitable for decentralized use, but also can focus on the construction of large-scale photovoltaic power stations to lay the foundation for future economic development prospects for renewable energy.
Make full use of various preferential policies of the country to accelerate the development of photovoltaic new curtain wall and meet the social responsibility requirements for energy saving and emission reduction in China.