1: https://en.m.wikipedia.org/wiki/High-voltage_direct_current
The only problems are that the day-night cycle still exists and storage is expensive, that it would be a massive capital investment, and that the governments of most countries in the Sahara aren't very stable.
In 2011, France and the US forced a regime-change that resulted in civil war and de-facto partition of the country. I would expect most of that investment has been destroyed by now, and the security situation is unlikely to be stable enough to restart this sort of grand plan for at least a decade.
In the meantime, Morocco (faithful French ally, an absolute monarchy with extremist-Islam undertones) started its own effort, which is now considered to be the largest solar-panel plant in the world: https://en.wikipedia.org/wiki/Ouarzazate_Solar_Power_Station