Jackie Chan Discs Help Boost Solar Panel Efficiency

wbr1 writes Apparently the pit pattern on a blu-ray disk is great at helping trap photons, rather than reflecting them. Applying this pattern to the glass in a solar panel can boost efficiency by 22%. Researchers at Northwestern tested this system with Jackie Chan discs. From the article: "To increase the efficiency of a solar panel by 22%, the researchers at Northwestern bought a copy of Police Story 3: Supercop on Blu-ray; removed the top plastic layer, exposing the recording medium beneath; cast a mold of the quasi-random pattern; and then used the mold to create a photovoltaic cell with the same pattern....The end result is a solar panel that has a quantum efficiency of around 40% — up about 22% from the non-patterned solar panel."

Comments

BLUE ray

[Spy Handler]

The pits on a blu ray disc are optimized for reading with a blue laser. Sun's output have more energy at the other end (red spectrum). I'm thinking they might get even better efficiency if they tried a disc pitting pattern that was meant for reading with a red laser.

Re:BLUE ray

[pavon]

Now that they have a proof of concept, it is an obvious thing for researchers to try different pit sizes and patterns in order to optimize the efficiency

Actually, that already happened. As the abstract of the paper notes, previous research has already identified how to theoretically optimize patterns, but arbitrary patterns require expensive photo lithography equipment to create. This research shows that an existing inexpensive mass production technique generates results that are almost as good as the optimized patterns, but not quite as good because the spacing of the pits is a bit too periodic (especially across tracks rather than along them).

Re:BLUE ray

[Anonymous Coward]

removed the top plastic layer, exposing the recording medium beneath; cast a mold of the quasi-random pattern; and then used the mold to create a photovoltaic cell with the same pattern

So you use your expensive photo lithography equipment to create a master, make as many molds from that as you like, and then create the photovoltaic cells from those. The mass production of BD-ROM discs is irrelevant, it just makes your master cheap, but when you're making 10,000s of cells the cost of the master is unimportant.

Re:when dirty?

[wbr1]

The data density in bluray means that the pits are far, far, far, far too small for dirt to get stuck in, or on. Think of it like placing a pebble on a beach. There are pits between sand grains but the size disparity means it acts like a flat surface for most intents and purposes.

Not only this, but presumably the pits can be under the glass, just as they are under polycarbonate on a disc. Then the pits are not exposed to dir, and a normal washing will remove surface dust, bird poop, etc.

Re:Copyright?

[BronsCon]

I don't know... I can replace the batteries in my $5 calculator every year, or I can have a solar cell in my $5 calculator and never replace the batteries, because there aren't any. That's just one practical application where they're quite economical; there are many others, but I'm not up to the task of wasting my time doing your research for you, so you can seek them out yourself if you're interested.