Guides and answers / Solar and batteries

QUESTION · SOLAR

Why do we fit solar panels with glass on both sides?

THE SHORT ANSWER

Many older solar panels have a white plastic laminate on the back, and that laminate breaks down over time. Panels with tempered glass on both sides, called dual-glass or bifacial panels, hold up better. The old panels in our video were 15 years old and already failing at the back. We expect 20 to 25 years from a dual-glass panel.

Mountain Man ElectricalElectrical Contractor Licence 88209 · Updated October 2026
FILMED ON THIS JOBReplacing old solar in Kelso without losing the 44 cent feed-in tariff

Dual-glass solar panels and the old laminate-backed panels they replaced. 45 sec.

The difference between the two kinds of panel

A standard panel has glass on the front and a plastic laminate sheet on the back. A dual-glass panel has tempered glass on the front and on the back.

What happens to the laminate over time

The panels in the video came off a roof in Kelso after 15 years. The laminate on the back had broken down, and it is one of the main faults we see on older panels.

How long a dual-glass panel should last

We expect 20 to 25 years from a dual-glass panel, which is why it is the panel we prefer to fit.

Where this came up

On the Kelso job the owner wanted new panels without losing his 44 cent feed-in tariff. We replaced the system at matching capacity with dual-glass panels, and the full story is in the Kelso case study.

Panels on your roof getting old?

Tell us how old the system is and what tariff you are on. We will tell you what a replacement would involve.

Start with a job like this

Step 1 of 3. Contact details come last.