Mining in the Sahara Desert seems problematic. There is the problem of the heat.
On a first glance, yes. There are much better places for renewable-based mining, like the Chilean/Bolivian Altiplano, and some regions in Central Asia and Southern Africa for solar or Argentine Patagonia for wind energy.
But there are some "cooler" spots in the Sahara, too - above all, the regions near the Atlantic, for example near Agadir, Sidi Ifni or in Western Sahara, where summer temperatures are pretty similar to Central European countries like France or Germany. I guess that would be an interesting spot for a wind farm combined with mining equipment. And land should be extremely cheap there. As Morocco is trying to "secure" the Western Sahara region, and Agadir also is a popular tourist destination, the State has invested in infrastructure in the region, so the Internet connection should not be that bad, too.
And if energy is cheap, then cooling should be cheap, too.
Edit: I didn't find the exact location, but
this map on the Soluna website suggests the farm will indeed be located on the coast of Southern Morocco, which is the windiest region of the country (and one of the windiest of Africa).