Solar power requires a relatively clean environment for photoelectric or mirrored steam systems.
The Shara is a very dusty desert. Dust quickly covers everything.
Wind power requires cooling. Generators do generate a substantial amount of heat. The Shara is hot. If the generator cant dissipate the heat they quickly shutdown or fail. The generators also will quickly fail due to the abrasive nature of the Sharas very fine sand and dust getting in to the mechanical workings of the generators.
The Shara is a very hostile environment for most anything man made. Anyone who attempts to build anything in the Shara had better build a pilot version of whatever it is first so they can learn from their failure
Is there a reason you spelled it Shara throughout your entire post instead of Sahara? Just curious.