It is unknown if they will ever be as cost-effective or efficient as conventional photovoltaic cells.

The term nantenna (nano-antenna) is sometimes used to refer to either an optical rectenna, or an optical antenna by itself. In 2008 it was reported that Idaho National Laboratories designed an optical antenna to absorb wavelengths in the range of 3-15 um. These wavelengths correspond to photon energies of 0.4 [[Electronvolt down to 0.08 eV. Based on antenna theory, an optical antenna