have a tank of water painted black sitting on the sand, water vapor pressure pushes turbines,

Water vapor by itself at any temperatures of unconcentrated sunlight would heat, wouldn't come close to the tempurature needed to turn a steam turbine to generate power. Most steam driven power plants have the steam be at about 500 °C. There is no place on Earth that would get even close to that by just placing a black painted barrel of water in direct sunlight.

You're not wrong in your general idea, but just the scale. The approach you're describing is close to how Concentrated solar power works. The idea to get up to those crazy high tempuratures from sunlight is to use mirrors to reflect a huge amount of sunlight on one small space. It looks like this:

There are a number of these built around the world. In fact, the solar thermal energy is so high its heating molten salt, which is later used to heat water to steam to turn a turbine generating power.

While Concentrated Solar Power works in both theory and practice, it has not been found to be more efficent for generating electricity in 2026 than just using a giant amount of Photo Voltaic solar panels instead. Many of the Concentrated Solar Power installations are being shut down because of this.