Is it possible to create a layer over a solar panel to change the colour of it?

Depends on what you use. If you block any of the light, you lower the efficiency of the solar panel. White is bad, as white means all incident light is reflected equally, so little or none gets through to the solar cells.

Why would you want to do this?

You can change the colour easily by placing a coloured pane of glass over the solar panel. This will reduce the efficiency of the panel. The only other possibility is to change the active chemical. Naturally solar panels will tend to be the same colour as the active substance. Choose a different substance and you change the colour. Of course, by using something other than the best substance your panel will be either more expensive or less efficient - probably both.

There is no such thing as one way glass. What you do is half silver a pane of glass. This means that half the light passes through the glass and the other half is reflected. If you put such a pane in a window between well lit room and a dark room then people in the well lit room will only see their reflection but people in the dark room can see the other room.

I can see why you might want to colour solar panels. It costs little more to clad a commercial building in solar panels (including the control gear) than it does to use conventional cladding providing that it is done at build time. This gives free electricity to run such things as air conditioning. The main problem is that these buildings do not look good. If you can apply a decorative coating then maybe there would be a better uptake of this technology.

As a quick contribute, the blue colour of the panels is from an ink made specifically for the panels to maximize their efficiency. Its nice that you want to decorate but you are missing the whole point of the panel, to convert light to electrical energy for the battery banks as efficiently as possible.

GL>

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