"Photovoltaic has still many recent discoveries for great efficiency improvements, and more are likely to come."
Except you can not exceed the solar power that hits the surface of the planet from the sun. Sorry kids but once again that damned law of physics get's tin the way.
Solar has a Maximum you can not exceed and that is if the sky is clear on a low humidity day and not pollution in the sun belt. Everywhere else is drops off drastically. Solar is awesome for a supplemental power source or to offset consumption. On homes that are grid tied and allowed to back-feed it can do a lot to offset Air conditioning power, but on cloudy days or in winter solar is worthless so you need other sources as your main power supply.
Yes you CAN go 100% solar, but that means oversize installations. 5X the solar needed to capture and store as much power as possible for the longest historical 10 year no sunlight stretch. in some places that is 2 months, so you also need battery storage to handle 2 months plus 15% and a solar installation that can charge up that 2 month supply within a few days.
So no, Photovoltaic will not be the answer, too low of energy density even if it was at 100% efficiency.