cross-posted from: https://slrpnk.net/post/24690127
Solar energy experts in Germany are putting sun-catching cells under the magnifying glass with astounding results, according to multiple reports.
The Fraunhofer Institute for Solar Energy Systems team is perfecting the use of lenses to concentrate sunlight onto solar panels, reducing size and costs while increasing performance, Interesting Engineering and PV Magazine reported.
The “technology has the potential to contribute to the energy transition, facilitating the shift toward more sustainable and renewable energy sources by combining minimal carbon footprint and energy demand with low levelized cost of electricity,” the researchers wrote in a study published by the IEEE Journal of Photovoltaics.
The sun-catcher is called a micro-concentrating photovoltaic, or CPV, cell. The lens makes it different from standard solar panels that convert sunlight to energy with average efficiency rates around 20%, per MarketWatch. Fraunhofer’s improved CPV cell has an astounding 36% rate in ideal conditions and is made with lower-cost parts. It cuts semiconductor materials “by a factor of 1,300 and reduces module areas by 30% compared to current state-of-the-art CPV systems,” per IE.
well, adding lenses kinda requires motorizing the panels to track the sun, right? otherwise the “hot spot” is going to move around across the day/year
is there a way to shape the lens to mitigate this?
You make them convex.
You can shape them that no matter how the light falls on it, it will align to the center. Kind of like how satellite dishes work but in reverse.
how do you do this, actually? I’m curious about the details because I just watched a video on compound parabolic reflectors, haha
a regular (ideal) convex lens with a single focal point will have the image move around as the light source moves across the sky. AFAIK satellite dishes tend to be paraboloids, which focus parallel rays onto the focal point, and if you change the angle of the light source, you’ll start losing focus. Stuff like the DSN and radio telescopes absolutely do have to aim and track their targets (or are forced to follow the rotation of the earth).
satellite dishes that are aimed towards geostationary satellites don’t have to move (because their targets are stationary in the sky), while stuff like starlink tracks targets with a phased array.
Could have some refraction or hologram thing that bends the light the right way, maybe? Or like a matte glass that equalises the load.
Or why not just use (big) mirrors?
Won’t help with heat ofc!
I mean, this is a thing with solar concentrators already, haha
and for those the heat is a feature :p