Read more. Atmosphere and night tank ground-based solar by maybe 80% of what's possible. And, sand is a terrible thing to operate any efficient optics around. No, the desert is a fairly bad choice. Sure, it's kinda bright there, part of the day. That's about the only thing on the plus side.
The vast majority of telescopes are ground-based even though space is optimal for seeing, because the economics favor the ground by a wide margin. Same with solar: if you get 3 times the light in space per cell but it costs 100+ times as much to install and use, it's pointless.
And there's more than enough desert that isn't sand dunes. Even the Sahara is only 25% dunes.
