The location of home photovoltaics can generally be chosen on the roof of the house or on the open space. The conditions that need to be considered are the usable area, housing structure and load-bearing requirements, ground foundation conditions, and meteorological and hydrological conditions. If you choose to install it on your own roof, the load-bearing capacity of the roof must be greater than 20kg/㎡.
If the beams of the house are made of wood, don’t consider it. The service life of the photovoltaic system is as long as 25 years, and the wooden beams are perishable. It is recommended not to install them.
Herringbone roof
If a solar photovoltaic power station is built on a gable roof, the optimal inclination angle cannot be designed like that of a ground power station, and the front and rear shading distances should also be considered. In order to facilitate the combination of photovoltaic modules and the roof, the brackets are generally laid directly on the south-facing roof. The bracket is connected to the roof with a clamp, and the battery module is then installed on the bracket. This method is not only beautiful, but also maximizes the utilization of the roof area.
Flat roof structure
To build a solar photovoltaic power station on a flat roof structure, it is necessary to erect a photovoltaic support and design the optimal inclination angle and the front-to-back spacing of the modules.
own open space
If you choose to install it on your own open space, you can use anchor piles and concrete strip foundations as the support foundation, and which one to choose needs to be considered comprehensively based on geological conditions and costs. In addition, the design of the strength of the support foundation should also be based on the local meteorological conditions.
It should be noted that considering the thermal expansion and contraction effect of the components, it is better to have a distance of about 3cm between the upper, lower, left, and right components during installation.
Selection of grid-connected inverter
Grid-connected inverters are mainly divided into three categories: high frequency transformer type, low frequency transformer type and transformerless type. According to the designed system and the specific requirements of the owner, the type of transformer is mainly considered from two aspects of safety and efficiency.
The household distributed photovoltaic system is a small system and does not require high technical indicators. When the inverter does not have an isolation transformer, the energy conversion efficiency is higher. Considering factors such as cost, it is more reasonable to choose the transformerless type.
Lightning protection design
In order to ensure the safety and reliability of the photovoltaic grid-connected power generation system and prevent damage to system components due to external factors such as lightning strikes and surges, the lightning protection and grounding device of the system is essential. The solar photovoltaic power station is a three-level lightning protection building, and lightning protection and grounding involve the following two aspects:
1. Try to avoid the projection of the lightning rod falling on the photovoltaic module
2. The ground wire is the key to lightning protection and lightning protection.
Prevention of lightning induction: The metal sheaths of equipment, racks, metal pipes, and cables must be grounded reliably, and each metal object must be connected to the main ground line separately.