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Nanoantennas could make for more efficient solar panels

Nanoantennas could make for more efficient solar panels
Scientists from Tel Aviv University are creating what could be much more efficient solar panels, utilizing metallic "nanoantennas" instead of silicon semiconductors
Scientists from Tel Aviv University are creating what could be much more efficient solar panels, utilizing metallic "nanoantennas" instead of silicon semiconductors
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Scientists from Tel Aviv University are creating what could be much more efficient solar panels, utilizing metallic "nanoantennas" instead of silicon semiconductors
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Scientists from Tel Aviv University are creating what could be much more efficient solar panels, utilizing metallic "nanoantennas" instead of silicon semiconductors

Radio waves are a type of electromagnetic energy, and when they're picked up by traditional metallic antennas, the electrons that are generated can be converted into an electrical current. Given that optical waves are also a type of electromagnetic energy, a team of scientists from Tel Aviv University wondered if these could also be converted into electricity, via an antenna. It turns out that they can - if the antenna is very, very short. These "nanoantennas" could replace the silicon semiconductors in special solar panels, which could harvest more energy from a wider spectrum of sunlight than is currently possible.

The nanoantennas are constructed out of small amounts of aluminum and gold, and are each less than a micron in length - because light has such a short wavelength (as compared to radio waves), short antennas provide the optimal absorption. After being created, the nanoantennas were then exposed to light, to determine how well they could receive and transmit light energy. According to the initial tests, 95 percent of the wattage being absorbed by the antennas was passed along, with only 5 percent being wasted.

Not only are the nanoantennas efficient, but when their length is varied, the wavelength that they can absorb changes. Therefore, the researchers believe that one panel containing a variety of lengths of otherwise-identical nanoantennas could harvest energy from a much broader solar spectrum than is presently allowed by semiconductor technology.

To that end, the Tel Aviv team is now in the process of creating experimental plastic solar panels, nano-imprinted with varying lengths and shapes of nanoantennas. They are also looking into the electromagnetic-energy-to-electrical-current conversion process, with hopes of improving it.

Although silicon is not a particularly expensive material, the scientists believe that the superior efficiency of their panels could allow them to be smaller than present photovoltaic panels, and thus more cost-effective.

Similar research is also under way at the Idaho National Laboratory, where researchers have been developing plastic sheet solar panels stamped with nanoantennas.

7 comments
7 comments
Adrien
does
\"95 percent of the wattage being absorbed by the antennas was passed along\"
mean the same thing as:
95 percent of the incident light energy was converted into electrical energy?
If it does, why not just say that (which is what you guys say about all the other solar technologies you cover). If it doesn\'t, then the question is how much is converted, and why the attempted spin?
Stewart Mitchell
Nano-tube antenna might have potential as a component for a genetic bomb.Attached to rogue dna , the antenna could activate a poison with the right signal.
warren52nz
What a lateral thought on how to convert light into electricity! If it\'s more efficient than current panels and cheap enough, it could revolutionize the industry.
voluntaryist
Idaho National Laboratory won awards in 2007 for this work. They predicted a commercial product \"in a few years\". It\'s five years later and what happened? Why no update? Did it fail to pan out? Why?
Gizmag should do a follow-up on a technology that promises an 80% efficient solar cell.
dfvisser
Almost sounds too good to be true! Makes me wonder why nobody has thought of this before. We have known for a long time about the dual particle / wave properties of light.
Fred Schadeck
They are called rectennas (rectifying antennas) and have been around for most of a century. Tesla planned to use them with his grand New York transmitted power project.
It has been theorized for years that rectennas of a proper length could out do solar cells in a big way. Big as in over 90% efficient at absorbing and converting whatever frequency they are tuned to into electrical energy.
However there is a legal catch. When they determined that there was no way to meter and charge for transmitted power without wire they shut down Tesla and simply made using rectennas illegal.
Anumakonda Jagadeesh
Great advance in Solar Energy efficient utilisation. Congratulations on the fine research.