Snow On Solar Panels: How To Protect Your Solar Panel System From The Snow Load?

 

What is a snow load and how important is it to ensure a successful installation of your solar panel system? How to calculate snow load for your solar PV system? In this article, you will find answers to these questions.

The installation of solar panels must be carried out so that the solar PV modules are safely fixed to the roof for at least 25 years. This means a high demand for the execution of installation work as well as for the PV mounting systems, the materials and the fixing to the roof.

Some regions should be adaptable to an additional challenge, namely the large masses of snowfall.

Snow load map: Snow load zones

Snowfall is unequally distributed in the USA. To understand how high the snow loading could be it is worthwhile looking at the snow load map, which shows the three different snow load zones in the USA.

The intensity of snow loads increases from the South to the North zone. Certain regions can have more snowfall than its snow load zone.

 

Snowload Map: Copyright © https://homenation.com/zone-maps/

 

The snow loading of solar PV modules and the PV mounting system

Due to the settling of snow on the panels, the solar modules and the mounting system can be highly loaded.

Although it is assumed that snow slides off the inclined solar PV panels, it is not always the case. For one thing, a flat angle of inclination can prevent the snow from slipping off. Further, very wet snow can under unfavorable conditions stick together with other materials.

The snow loading depends on the snow load zone, where the solar PV system will be installed. In the USA, the snow load is between 20 and 40 pounds per square foot.

For information on how strong the weight load the solar PV system can hold: 10 cm wet snow weighs around 40 kilograms per square meter (8.19 pound per square foot)!

The resistance of the solar PV panels and the PV mounting system

The solar modules, as well as the PV mounting system, are naturally tested, and their loading capacity is given.

For regions with an extremely high snow load, there are unique solar panels with more resistant glass cover and particularly solid frame.

Snow load calculations

The standard ASCE 7-10 (Chapter 7 – Snow Load Calculations) includes the methods of calculation for the snow load. Also, the calculation formulas for the snow load on pitched roofs are found in this standard.

These equations can be used to estimate the snow load of diagonally mounted solar modules.

Online snow load calculator

An internet search will produce many snow load calculators, which will help to determine the snow load.

You need to enter your snow load zone, roof pitch angle and the altitude of your location. From this data the Snow load calculator determines the effective snow load, for which the solar PV panels and the PV mounting system should be designed.