Posted on 02/01/2008 5:11:26 PM PST by decimon
Researchers at Idaho National Laboratory, along with partners at Microcontinuum Inc. (Cambridge, MA) and Patrick Pinhero of the University of Missouri, are developing a novel way to collect energy from the sun with a technology that could potentially cost pennies a yard, be imprinted on flexible materials and still draw energy after the sun has set.
The new approach, which garnered two 2007 Nano50 awards, uses a special manufacturing process to stamp tiny square spirals of conducting metal onto a sheet of plastic. Each interlocking spiral "nanoantenna" is as wide as 1/25 the diameter of a human hair.
Because of their size, the nanoantennas absorb energy in the infrared part of the spectrum, just outside the range of what is visible to the eye. The sun radiates a lot of infrared energy, some of which is soaked up by the earth and later released as radiation for hours after sunset. Nanoantennas can take in energy from both sunlight and the earth's heat, with higher efficiency than conventional solar cells.
(Excerpt) Read more at inl.gov ...
Very good! That one I overlooked. However, I clarified my question in post #23.
In the case of the microwave oven, available energy is many times that of the solar energy that hits the earth's suface.
Still, a molecular dipole is an excellent example. Unfortunately, I never said that I was giving away a prize. Sowwy! Your reward is a pat on the back.
Agreed. Referring back to the original article, an optical rectenna would collect energy, but that energy would be very weak. If you could find a method to rectify the AC at such high frequencies, there would also be some loss.
Don't get me wrong... if one could capture the average 1.2kW/m2 of solar energy on a bright sunny day, this would be very useful. But there are obvious limitations in using a nano rectenna array tuned to the IR bandwidth to accomplish this. The first is that the IR component of the Sun's spectrum is only a small percentage of the 1.2kW/m2 hitting the earth's surface.
Another problem would be thermal stability of the array... at those frequencies, even the slightest expansion or contraction of the metal in the rectenna would severely detune it.
Even a PV cell will generate a useable ammount of energy with heavy overcast on a cold day. The rectenna wouldn't.
Has anyone tried to capture the abundant static electrical potential in the atmosphere? Even Art Bell marvelled at his longwire antenna in how it was able to generate 20,000 volts with enough current to knock someone to the ground. Low humidity + wind + an ungrounded antenna (more surface area, the better) = shocking results.
You can’t mention Art Bell and a long wire without recalling Tom Kneitel’s “Electricity Stealer” circuit.
You aren't thinking it all the way through again. As the antenna and material expand and contract, it would simply be tuned to a different part of the IR band, which in theory, would have approximately the same energy. Now, if he could get an antenna tuned to the ultraviolet frequencies, he could capture much more energy per sq meter.
bttt
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