Research conducted with partners Idaho National Laboratory (INL) and Microcontinuum Inc. (Cambridge, MA) is promising a method to build inexpensive solar energy technology to draw energy even after the sun sets. The solar cells would be imprinted on flexible materials via a special manufacturing process to “stamp” tiny square spirals or “nanoantennas” of conduction metal onto flexible materials, such as plastic. The nanoantennas can absorb approximately 80 percent of available energy versus current commercial solar panels which converts less than 20 percent of usable energy into electricity.
Each spiral nanoantenna is 1/25 of the diameter of human hair, making them absorb energy in the infrared section of the spectrum, just outside what is visible to the human eye. The sun radiates a lot of infrared energy, some of which is absorbed by the planet and released after sunset. The nanoantennas can absorb energy from both sunlight and the earth’s heat, making it much higher efficient solar product.
Although the nanoantennas can be easily manufactured, there is still a problem of creating a way to store and transmit the electricity since the frequency of the current switches back and forth ten thousand billion times a second, which is too fast for electrical appliances that operate on currents that oscillate only 60 times a second. The researchers are exploring ways to slow down the cycle.