The total world energy usage (coal + oil + hydroelectric + nuclear + renewable) in 2015 was 13,000 Million Ton Oil Equivalent (13,000 MTOE) - see World Energy Consumption & Stats. This translates to 17.3 Terawatts of continuous power during the year. Now, if we cover an area of the Earth 335 kilometers by 335 kilometers with solar panels, even with moderate efficiencies achievable easily today, it will provide more than 17,4 TW of power. This area is 43,000 square miles. ⁠ ⁠ The Great Saharan Desert in Africa is 3.6 million square miles and is prime for solar power (more than twelve hours per day). That means 1.2% of the Sahara Desert is sufficient to cover all of the energy needs of the world in solar energy. There is no way coal, oil, wind, geothermal, or nuclear can compete with this. The cost of the project will be about five trillion dollars, a one-time cost at today's prices without any economies of scale savings.⁠ ⁠ ⁠ ⁠ ⁠ #science #sahara #saharadesert #solar #solarpower #renewa...