How a solar panel is made

A panel is not a block of silicon with some wires on top.

1. 01Aluminium frame

   Encloses the entire laminate.

2. 02Front glass

   The thick, rigid protective front sheet. On its own it accounts for about two thirds of the panel’s thickness and 70% of its weight.

   Typical thickness 2.0 – 4.0 mm (typically 3.2 mm)

3. 03EVA

   Ethylene vinyl acetate: a transparent polymer film that bonds the glass to the cell.

   Typical thickness 0.40 – 0.60 mm

4. 04Silicon cells

   A screen-printed silver-based metallic paste, just a few microns thick, is printed on the cell surface to form the current collection grid.

   Typical thickness 0.15 – 0.18 mm

5. 05Tinned copper ribbons

   Ribbons and busbars interconnect the cells. They are not simply laid on top or removable: they are embedded and fused into the encapsulant. No thicker than a couple of sheets of printer paper.

   Typical thickness 0.15 – 0.30 mm

6. 06Second EVA layer

   Bonds the cells to the back of the panel.

   Typical thickness 0.40 – 0.60 mm

7. 07Backsheet

   The rear polymer sheet. In glass-glass modules it is replaced by a second sheet of glass.

   Typical thickness 0.30 – 0.40 mm

8. 08Junction box

   Connects the panel to the outside through the output cables.