What is Aluminium Backsheet in Solar Panels?
A backsheet is a protective layer located on the rear side of the PV module, commonly referred to as the solar panel. It serves as a barrier against various environmental factors that could compromise the module's performance and longevity.
When shopping for solar panels, it’s essential to be familiar with some common types of backsheets: white, black, transparent, aluminium, and copper.
In this blog post, we will delve into the details of aluminium backsheets.
Understanding aluminium backsheet
A PV backsheet is made up of multiple layers of polymers, adhesive materials, and other substances. The aluminium backsheet looks similar to a conventional backsheet, but the key distinction lies in its construction.
The aluminium backsheet incorporates a layer of aluminium foil in the middle. This central aluminium foil layer is sandwiched between protective layers positioned above and below it. These layers serve a dual purpose: safeguarding the aluminium foil from potential damage and shielding the solar modules from the diverse environmental factors they encounter during their operational life.
When is the aluminium backsheet used?
Aluminium backsheets find specific utility in photovoltaic panels designed using Copper Indium Gallium Selenide (CIGS) Thin-film technology. Unlike the popular solar panels that predominantly utilize polycrystalline or monocrystalline silicon, CIGS-based modules leverage CIGS as the primary semiconductor material responsible for absorbing sunlight.
CIGS thin-film modules, while offering distinct advantages, are notably more susceptible to moisture compared to their silicon-based counterparts. Herein lies the significance of the aluminium foil layer within the aluminium backsheet. The foil serves as a robust barrier that effectively prevents the ingress of water vapour and moisture towards the solar cells. This protective function is paramount in ensuring that the solar panel endures and maintains optimal performance throughout its operational lifespan.
While aluminium-based backsheets are primarily used for moisture-sensitive thin-film modules, their usage can also be extended to high-efficiency crystalline modules that exhibit greater sensitivity to moisture.
Some additional advantages
The aluminium backsheet has a lower static on the air-facing side. Because of this, it attracts less dust and dirt. This means solar panel owners can enjoy lower maintenance requirements, saving both time and effort on cleaning procedures.
Additionally, some studies show that a backsheet with aluminium film has high heat dissipation capability, which helps to keep the solar cells cool and operating at peak efficiency.