5 November, 2019
Vanessa Young visited Dr Nathaniel Davis’s lab to witness the concentrated capture of the sun’s energy.
In just one hour the earth receives more energy from the sun than humanity can use in a year. But capturing the sun’s energy has been famously hard – and expensive – because it is spread out of a large area.
When physicist Dr Nathaniel Davis left the hot Aussie sun of his homeland for a PhD position in the cooler climes of Cambridge University in the UK the sun followed him into his lab. At Cambridge, he worked on a technology called solar concentrators, clever materials that trap photons and send them sideways, where they can be caught by solar panels and made into electricity. He’s now brought this solar research to New Zealand where he is exploring how this technology will make solar technology more affordable.
In his lab, as he held up a small flat square of plastic it unexpectedly glows brightly from its edges. This is a luminescent solar concentrator.
“This material inside absorbs light and re-emits it. It basically traps light. This one is set in plastic, but it could equally be glass. I’m figuring out how to make new materials that trap the photons and send them sideways.”
The sideways part is key. By redirecting the photons to the thin edge of the glass or plastic sheet, then the solar panels themselves only need wrap around this edge to work. So instead of needing expensive solar panels stretching across the whole flat surface, as current solar panels do across a roof, it would require only a very thin strip of them around the edges of windows, for example...