|Supercop (Photo credit: Wikipedia)
As the world warms up to using solar panels and harnessing the immense energy that is reflected back from the Earth everyday, there are still some major hurdles that we need to overcome before we can rely on this technology for all our energy needs.
Cost of solar panels has been a major point of debate but as governments around the world are encouraging consumers to adopt this technology, there are considerable grants pouring in to reduce the cost of installing solar panels and that is welcome relief.
The efficiency of the solar panel itself has been questioned on many occasions. General estimates of efficiency of solar panels has been put at 10-15%, which basically means that
these expensive panels are only capable of converting 10-15% of light incident on them into electricity.
Unarguably, this does sound quite low. And has been picked up by detractors of renewable energy to ridicule.
But did you know that the efficiency of gasoline powered engines stands at a meagre 30%. In spite of automobile companies pooling in millions of dollars every year to improve the vehicles, we are able to convert just 30% of fuel that we burn into usable energy and the rest is just spent off as heat (No doubt your car needs a good cooling system other wise you would be chicken tandoori every time you drive that four wheeler of yours)
Never the less, solar panels still lag behind regular engines in terms of efficiency and there is definitely scope for improvement. Researchers Alexander J Smith and his colleagues at North Western University set out to change this and decided to work on increasing the absorption of the solar panels. As luck would have for them, they found a better method of making solar panels in technology that already exists and is already in common use, i.e. Blu Ray Discs.
As you might already be aware, Blu-Ray discs are known for their superlative storage capacity and are currently serving us by storing our favourite movies in full HD. Blu Ray manage this by storing the 0’s and 1’s of the binary code in a more compact manner than regular CD’s and DVD’s and reading them more efficiently with a blue coloured laser. However, we do not really need to understand the nitty-gritty of how blu ray discs work here. What Smith and his colleagues found is that simply replicating the pattern of how data is stored on blu-ray discs also improves absorption in solar panels.
In order to test their hypothesis, Smith and colleagues simply copied the code of Jackie Chan‘s popular movie Super Cop on a solar cell and observed that absorption in the modified solar cell was much better than a regular one and the efficiency of the solar panel rose way up to 21.8%. The researchers attribute this increase to data compression algorithm that is used in Blu-ray discs and While this was under test conditions and the efficiency might turn out to be a bit lower when used on the field, there is significant increase in efficiency of the solar panels, and one that brings it closer to machines that we use everyday.
Since Blu-Ray technology is something that is well known, application of this finding to solar panels should neither be time consuming or expensive, bringing further cheer to users to solar technology and its supporters!
Smith AJ, Wang C, Guo D, Sun C, & Huang J (2014). Repurposing Blu-ray movie discs as quasi-random nanoimprinting templates for photon management. Nature communications, 5 PMID: 25423591