Green Tech: Super Efficient Nanoantennas Will Solve The World's Energy Problems... Maybe

A new flexible sheet of nanoantennas developed by the U.S. Department of Energy could help solve the world's energy problems with its super efficient design.

The nanoantennas, consisting of nano-sized gold spirals or squares set in polyethylene, absorb and convert infrared radiation into electricity at an efficiency of 80%! Compared to the 15-20% efficiency of traditional solar cells, these nanoantennas are set to revolutionise the solar power sector.

Because they absorb and convert infrared energy, they can also make electricity at times and places solar cells cannot, e.g. from the latent heat released by the Earth during the night. The nanoantennas can also be used as a cooling system for electronics, buildings, and factories; converting excess heat energy into electricity. The flexible nature of their construction also means the nanoantennas can be incorporated into the skin of many consumer devices to provide power from nearby heat sources - even the user's own body heat!

There's one big problem, however: the nanoantennas currently produce electricity with an AC current that oscillates trillions of times per second, making it unusable in current devices. There is currently no modern rectifier technology that can covert this super alternating current into a more usable state (for comparison purposes, your wall outlet provides an AC current that oscillates at a rate of 60 times per second.) In order to convert the output to usable electricity, we need to develop nanoscale rectifiers that "need to be about 1,000 times smaller than current commercial devices."

With an efficiency of 80%, I hope they get crackin' on those rectifiers!

Flexible nanoantenna arrays capture abundant solar energy [EurekAlert]
[via: Engadget]