Silicon is the main material used in both computers and solar panels.
Sand is silicon.
Deserts have a lot of sand and sun.
This may be an oversimplified way of looking at things, but could we create a self-reproducing robot (nano or otherwise) that, placed in a desert, could spread using nothing but the materials that could easily be found in a desert and the energy from the sun? Or would additional resources be required?
If additional resources are needed, what is the best way to accomplish this with minimum human effort?
Basically, I'm looking for an artificial "plant" that would grow into a silicon "forest" which could capture most of the solar energy that falls on the desert, and could be used as a power source for humans.
Time is not a factor (this is a long-term project).
EDIT: Since the AI is currently beyond human technology, but is within the realm of plausibility, the hard-science part specifically applies to the materials and energy requirements. Assume that computers, assemblers, solar panels, etc. require the same materials that they use today.
Example: If rare elements not readily available in a desert are required to construct a computer, we have a problem (though if the quantity-per-unit is small enough that they can be provided with the initial "seed", you may mention that.)
Example 2: If solar power is insufficient to perform some of the operations used in the construction, we also have a problem. Solar collection does not need to be entirely photovoltaic (i.e. using solar heat directly is fine) as long as there is a method of constructing the solar-powered device using the materials and energy available.