Thank you, Vladimir.

Current solar energy is a foolish investment because it only converts energy from the infrared portion of the EM spectrum into electricity. The new layered solar cells will absorb light from more of the spectrum dramatically increasing it's efficiency. The problem is getting the hexagonal structure of these materials to line up perfectly to improve efficiency. Only then will solar cells become an efficient source of energy.
THAT makes sense.

Solar is not going to be practical for a while. Not until they can figure out how to make all the little hexes line up a row.
but that was so vague as to not really convey any sense. It implies firstly that ALL solar power is photovoltaic, which it isn't, and that multi-layered PVs are the only PVs, which they aren't, and you don't really specify what you mean by "practical". To my mind "practical" means it works - which current technology does, and there are applications where it outperforms grid-connected supplies from conventional sources. It's a matter of appropriateness.

But you cannot dismiss an entire field of endeavour based on the difficulties of only one branch of research.

Commercial PVs to date can vary from 1-15+% efficiency, and improvements would be highly welcome, but there are plenty of existing systems using current technology making significant contributions, with or without their little hexes lined up