To build a self-sustaining robot society will require reliable electric power and that must come from solar electric power sources. A million-year survival plan requires reliable energy sources far beyond what modern fossil fuels can provide. To get large supplies of electric energy will require large solar farms and to make these reliable in the long term means that they must be totally constructed and maintained by robots. This may be possible even now if the component pieces are made in a standardized way that is specifically designed for robots.
“California’s Topaz project is the largest solar power plant in the world with a 550 MW capacity, and it is now in full operation.” It is shown in the photo above in their site’s post showing the construction being assembled by humans, but it is easy to imagine a robot machine being designed to put these base structures into position, and another robot to put the panels on the bases, and another one to hook up the electrical wiring. If those machines were themselves designed to use electrical power instead of petroleum power, the electrical power they just installed would be used to construct more solar fields and soon without further human input they would be able to cover these hills with similar panels.
The components can be brought from their factories by self-driving long-haul trucks directly to the exact site of current construction. The base towers and solar panels and their equipment-hauling trailers could be designed so the equipment already described could offload the components placed into their final position for their use in creating electricity. The trailers would be delivered to the final construction sites and the panels removed one by one for use to eliminate storage and multiple handling.
The point is that something that seems as complex as powering a robot society might be easily done if all of the components are set up for robot construction and maintenance. The bases of the solar panels seen above could easily be built by a robot factory, and probably if designed for robot use would be much sturdier and more (antifragile)/flexible.
What needs to be done now is to design each of the various components of the system to be robot ready. That is, that every part be designed with components for easy robot understanding, that is, with visibility, gripping, moving, removing, and replacing everything.
The original cost of designing and manufacturing the robots listed for the field work above would be high, but once they were fully functional the cost would drop to nearly zero for making infinitely large solar-power farms.
There are better things for humans to be doing than the field work seen above.