How to calculate how many watts of solar panels to install at home?
The amount of solar power you need to install depends on the available area of the installation location. For modular installation, you can install 150W per square meter, while for sloped installations, it's 100W per square meter.
In the actual installation process, the roof area must be significantly larger than the area required for the solar panel array, mainly due to factors like obstructions or protrusions on the roof. A key factor here is the effective area.
There are generally three types of roofs used for solar power installations: color steel tile roofs, ceramic tile roofs, and flat concrete roofs. The installation method and the required area differ depending on the type of roof. (Taking crystalline silicon panels as an example):
Color Steel Tile RoofFor steel-structured color steel tile roofs, solar panels are usually installed only on the south-facing side. The installation ratio is 10 square meters per 1 kW, meaning a 1 MW (1000 kW) project would require 10,000 square meters of roof area.
Ceramic Tile RoofFor ceramic tile roofs, solar panels are typically installed in unobstructed areas of the roof. Although the installation method is different from that of color steel tile roofs, the coverage ratio is similar, at around 10 square meters per 1 kW. This means that a relatively large (100-150 square meters) brick-tile roof can accommodate about a 10 kW solar power system, generating an estimated 9,000 to 13,000 kWh of electricity per year over 25 years.
Flat Concrete RoofFor flat roofs, to ensure the panels receive as much sunlight as possible, the optimal tilt angle must be designed. Therefore, a certain gap between rows of panels is required to prevent shading from the row in front. As a result, the roof area required for the project will be larger than the area needed for the flat installation of color steel or villa roofs.
This is how Hengyuantai explains how to calculate how many watts of solar power to install at home.