Sustainable Greening of Sahara

Greening the Sahara Desert can only be possible with low finance requiring steps. Additionally, each step should generate revenue quickly to trigger the next one. Big projects require momentum to be successful. The strategy including its Plan B should keep up the momentum. I see humans and fuel as the slowing factors in big construction projects. Therefore, I try to utilize swarm robots with renewable energy sources on site. As a result, much less logistic is required in the harsh project area. Treat the Sahara project like a construction project in Mars. You would design it with minimum human resources and minimum logistics from Earth. You would try to maximize the local energy sources and raw materials. Now apply it on Sahara (or Suez and Panama Canals). 

I propose deep water tunnels from the Mediterranean Sea to the inners of the Sahar desert. As the water is consumed from the land, more sea water would be pushed from the sea. The filters placed under the sea would make most of the filtering by the help of the water pressure, reducing the operational cost. Farming areas would be formed starting from the shore. This would increase the investment return rate even before reaching the desert. Most of the farming will be done using robots that use electric, no diesel tractors. The electric would be generated partially by sun concentrators (solar panels are not ideal in deserts) and piezo film wind electric generators (classic wind turbines are not ideal due to sand storms damaging the moving parts). 

The remaining salt on the filters would be either sold as table salt or used as MagNa rocket fuel. Additionally desert sand is rich with Uranium and some other minerals which would be sold to further finance the project. Local workers would work in cities where they would build the required infrastructure in factories. Electric operating mono rail trains would transfer the crops and ores from the desert to the port and carry the infrastructure to the desert. Almost no men in desert!

Building such an infrastructure may look expensive but once they are build, they would have much lower operating cost and less onsite maintenance. Cheaper alternatives preferred initially become exponentially difficult problems to be solved later which slows and even stops such mega projects.