Expensive, ugly, and giving little in the way of power-bang-per-buck, solar panels look likely to be edged out by more elegant photovoltaic technologies. Some can be printed like ink on just about any surface – curtains, walls, windows – while others, such as glass bead Sphelar cells, rely on improving existing silicon technologies.
Commercial ink-printed cells might still be a little way off but the transparent Sphelar globular cells that absorb light from all directions – unlike existing solar panels that reflect back much of the light that hits them – are available now.
According to its makers, Kyosemi, the new spherical technology can improve efficiency by as much as 25 per cent. And because it is see-through it can be used in window glass to generate power for the home almost invisibly. It can also be inserted into slim, bendable materials such as plastic, making it extremely versatile.
Sony, meanwhile, has come up with its own electricity-producing solar windows, which use light-sensitive ink, giving them a stained glass effect. With little power generated for the moment, however, more refinement is needed on the prototypes before they appear in homes and offices.
The same goes for other dye-sensitised solar cells being prepared for the market, such as organic thin-film versions that can be used like paint. But once they are perfected, think of the fun that graffiti virtuoso Banksy could have.