I don't know if y'all have seen this (I read about it last year) but it's a means of collecting solar energy in the mid-infrared spectrum at efficiencies around 80% and up to 92%. Currently, the main problem to be solved is the fact that the antennae make high-frequency electricity, i.e., in the tens of trillions of cycles! So, stepping that down would incur a loss of efficiency, unless they can do it electronically. I have to wonder if some of Nikola Tesla's research into high-frequency electricy would help here.
And as this collects energy from the infrared spectrum, you could make electricity at night :D
Here are some links to read further. The MJ interview with Steven Novack probably has the most information about the technology and how it would be put to use.
Q&A: Steven Novack | Mother JonesNanoantennas, a new, more efficient method for solar power?Flexible nanoantenna arrays capture abundant solar energyAn array of solar antennae