With the addition of some cheap nanoantennas, your average window can now be turned into an efficient solar heater.
Just as Elon Musk’s Tesla wants to turn our otherwise dormant roofs into powerful solar energy generators, scientists are working on transforming our windows into efficient solar power sources.
With a relatively straightforward process, they have shown that glass windows can be turned into solar-powered heat screens using plasmonic nanoantennas.
Made of nickel-aluminium sandwiches, the nanoantennas are shaped like nanoellipses, which are then patterned as a solar array onto the glass.
Evidence from testing has shown that when sunlight shines onto the surface of the antennas, light is more efficiently absorbed on the front side rather than the back.
This is crucial as it allows the sunlight to be absorbed in much greater quantities from the surface facing outside and yet appears almost completely transparent to those looking from the inside or outside of the window.
Can be ‘painted’ on
Its greatest benefit, the researchers said, was not to make windows a source of solar energy, but to keep them from being cold. When you’re trying to keep a house warm in winter, cold windows act as a major heatsink and can be one of the biggest contributors to high energy bills.
This new solution will offer the ability to heat the windows by several degrees through the sun alone, therefore offsetting any wasted energy and high costs. The researchers said that it is relatively simple to apply to any windows and doesn’t cost that much to install as it is effectively ‘painted’ on.
It is also being suggested that the nanoantennas could have other applications with any surface that requires heating, possibly used in energy storage.
The next stage of research will look at how the nanoantennas could achieve even greater temperature increases by absorbing light through sources such as ultraviolet and near-infrared radiation.