BIPV stands for Building Integrated PV, which is the integration of photovoltaic buildings. PV stands for Photovoltaic. BIPV technology is a technology that integrates solar power (photovoltaic) products into buildings. Building Attached PV (BIPV) is different from the form in which the photovoltaic system is attached to the building (BAPV: Building Attached PV). In modern society, people's pursuit of a comfortable building thermal environment is increasing, leading to increasing energy consumption of building heating and air conditioning. In developed countries, building energy has accounted for 30%-40% of the country's total energy consumption, which has restricted economic development to a certain extent.
BIPV building is first of all a building, it is an architect’s artwork, and the key to its success is the appearance of the building. In BIPV buildings, we can hide junction boxes, bypass diodes, connecting wires, etc. in the curtain wall structure through related designs. In this way, it can prevent direct sunlight and rain erosion without affecting the appearance of the building, achieving a perfect combination with the building and realizing the ideas of the architects.
For buildings, light is the soul, and its requirements for light and shadow are very high. The BIPV building is a double-sided glass component made of smooth super white tempered glass. It can achieve a specific light transmittance by adjusting the arrangement of the cells or using perforated silicon cells, even in the sightseeing areas of the building. Transparency requirements. Of course, the greater the light transmittance of the photovoltaic module, the thinner the arrangement of the cells and the smaller the power generation.
BIPV modules not only need to meet the performance requirements of photovoltaic modules, but also meet the requirements of the three experimental requirements of the curtain wall and the safety performance requirements of the building. Therefore, it needs to have higher mechanical properties than ordinary modules and adopt different structural methods. In different locations, different floor heights, and different installation methods, the mechanical properties of its glass may be completely different.
The double-glass photovoltaic module used in BIPV buildings is composed of two pieces of tempered glass, the middle is composed of PVB film composite solar cells to form a composite layer, and the cells are connected in series and connected in parallel to collect the lead ends as an integral component. The thickness of the tempered glass is the result of strict mechanical calculation in accordance with the national building code and curtain wall code. The PVB film in the middle of the module has good adhesion, toughness and elasticity. It has the effect of absorbing impact and can prevent the impact from penetrating. Even if the glass is broken, the fragments will firmly adhere to the PVB film and will not fall off. Injury to people, so that the damage may be reduced to a minimum and improve the safety performance of the building.
Easy to install
BIPV building is a close combination of photovoltaic modules and glass curtain wall. Since the development of curtain wall in our country for 30 years, various types of curtain wall have relatively mature design and installation technology. The component-type curtain wall has flexible construction methods, strong adaptability of the main structure, and mature technology. It is currently the most used structural form. The unit curtain wall is processed in the factory, which is easy to realize industrialized production, reduces labor costs, and controls the quality of the unit, thereby shortening the construction period and bringing greater economic benefits to the owner. The double-layer ventilated curtain wall system has the advantages of ventilation, heat insulation and sound insulation, energy saving and environmental protection, and can improve the heat dissipation of BIPV modules, lower the temperature of the cells, reduce the efficiency loss of the modules, and reduce the heat transfer to the room. To put it simply, BIPV building uses BIPV photovoltaic modules to replace ordinary tempered glass, and its structural form is basically compatible with traditional glass curtain walls. This makes the installation of BIPV photovoltaic modules have a deep technical foundation and advantages, and can fully meet the requirements of convenient installation.
The glue used for the encapsulation of ordinary photovoltaic modules is generally EVA. As the anti-aging performance of EVA is not strong and the service life is less than 50 years, it cannot be the same life as the building and the yellowing of EVA will affect the beauty of the building and the power generation capacity of the system. The PVB film has the characteristics of transparency, heat resistance, cold resistance, humidity resistance, and high mechanical strength, and has been maturely used in the production of laminated glass for construction. The domestic glass curtain wall specification also clearly puts forward the "application of PVB" regulations. BIPV photovoltaic modules use PVB instead of EVA to achieve a longer service life.