Building-integrated photovoltaics (BIPV) centered on grid-connected photovoltaics (BIPV) currently accounts for the majority of the photovoltaic market share. So, what are the main forms of BIPV?
The integration of photovoltaics with buildings currently takes two main forms:
1. Integration of building and photovoltaic systems
Building-integrated photovoltaic (BIPV) systems involve installing encapsulated photovoltaic modules (flat or curved panels) on the roofs of residential buildings or structures, connecting them to inverters, batteries, controllers, loads, and other devices, and connecting them to the external power grid. The photovoltaic system and the power grid are connected in parallel to supply power to the residence (user), with excess power fed back to the grid and insufficient power drawn from the grid.
2. Integration of building and photovoltaic modules
The further integration of building and photovoltaics involves integrating photovoltaic devices with building materials. Conventional building envelopes use paint, decorative tiles, or curtain wall glass for protection and decoration. If photovoltaic devices replace some building materials—that is, if photovoltaic modules are used for roofs, exterior walls, and windows—they can serve both as building materials and generate electricity, making the most of their properties. For photovoltaic devices to be used as building materials, they must meet several requirements: durability, thermal insulation, waterproofing, moisture resistance, and appropriate strength and rigidity. If used in windows or skylights, they must be able to transmit light, meaning they can both generate electricity and allow sunlight to pass through. In addition, safety, aesthetics, and ease of construction must also be considered.
In addition, two important factors should be considered when integrating photovoltaic modules with buildings:
1. To ensure high photoelectric conversion efficiency of photovoltaic modules, the ambient temperature around the modules must be kept as low as possible. This requires good ventilation around the modules. Therefore, when designing and installing photovoltaic modules, consider using overhead structures, double-layer ventilated roofs, or double-layer glass curtain walls.
2. The lifespan of photovoltaic modules is typically 15 to 25 years, while the lifespan of building envelopes is typically 50 years. Therefore, the requirements for disassembly and replacement after photovoltaic module failure must be considered during the design process.
