Think about your roof if you can install solar panels, then it will bring sufficient power supply to your home or business, and also contribute to energy saving and creating a green life. This post will analyse your roof’s suitability for installing solar panels in 8 key points and the alternatives if it is not suitable.
1. Roof Orientation
If you are in the southern hemisphere, then a north-facing roof is the best choice. South-facing roofs are not recommended for installing solar panels.
If you are in the northern hemisphere, then a south-facing roof is the best choice. This is because the maximum amount of solar power is generated between 10am and 3pm in the middle of the day.
Regardless of whether you are in the southern or northern hemisphere, you can install solar panels if your roof is facing east or west, but the amount of sunlight radiation in the morning and evening is not very high, so the power generation efficiency is average.
2. Type Of Roof
Both horizontal and inclined roofs are suitable for installing solar panels. In the case of a horizontal roof, the mounting of solar panels can be designed for the optimal tilt angle appropriate to the latitude of the region. If the roof is tilted, then the panels can be laid flat directly on the roof.
3. Calculate The Total Power Of Installable Solar Panels According To The Roof Area
1. Fixed on a horizontal concrete roof: total power of installable solar panels = 150W/m²×roof area.
2. Fixed on the inclined color steel or tile roof: the total power of installable solar panels = 210W/m²×roof area.
It should be noted that the above is only an estimate, for horizontal roof installation of solar panels, the distance between each row of solar panels need to be calculated according to the latitude of the location and need to be designed according to the actual situation. Such as the height of the daughter wall, whether you need to leave space for operation and maintenance, whether there is other equipment on the roof, air outlets and other circumstances to decide.
4. Roof Material And Load-Bearing Capacity
If it is a cement horizontal roof, it is generally no problem, because the average pressure of the solar panel system plus the bracket plus the cement pier on the roof is 30kg/m², and the general roofs are more than this value.
If the roof is made of steel tiles or bond tiles, we will use aluminium alloy solar panel mounts, which are lighter and will not rust. The average pressure of the solar panels and mounts on the roof is about 15kg/m², while the average pressure of steel tiles and tiled roofs is 20-30kg/m². Therefore, it can be installed.
In addition, we sometimes have to consider the fixed load of the roof, wind load, snow load, earthquake load, etc. to determine whether your roof is suitable for installing solar panels.
5. Roof Quality And Life Expectancy
You need to use your discretion with roofs that are made of wood, or roofs that do not have very good load-bearing capacity and have not been repaired for many years, because the life expectancy of PV modules is usually greater than 30 years at the time. You need to make sure that the roof will not have quality problems during the lifetime of the PV panels.
6. Whether The Sunlight On The Roof Is Blocked Or Not
The sunlight on a certain area of the roof is often blocked because of some trees, other buildings, daughter walls, etc. This, this time we have to make appropriate avoidance of this situation, especially at noon. Because the sunlight of a certain PV module is blocked will cause the power of the whole string of PV panels to drop. If you can not avoid the occurrence of this situation will be blocked PV panels to add a solar optimizer, which can be a good solution to this problem.
7. Whether The Roof Will Leak After The Installation Of Solar Panels
It is necessary to assess whether your roof will leak as a result of installing PV panels before installing them, and our design solutions are usually designed to avoid such a situation.
8. Compliance And Policy Support
It is necessary to check with the local government whether it is possible to install PV panels on the roof and whether there are requirements for the size of the panels. For example, in Germany it is not permitted to install PV panels larger than 2m² on a single roof, and in Italy only black PV panels can be installed on certain scenic rooftops. You can also ask for information on whether there are government subsidies for installing PV panels in your local area.
9. What Should I Do If I Can't Install Solar Panels On My Roof?
You can consider installing PV panels on carport, yard grass, balcony, etc. These are the places where PV panels are often installed.