The solar energy and solar farms are used to generate energy and reduce dependence on oil (or for environmental purposes). The maintenance, operation, optimization, and repairs in big farms become very difficult, expensive, and inefficient, using human technicians. Thus, here, we teach using the robots with various functions and components, in various settings, for various purposes, to improve operations in big (or hard-to-access) farms, to automate, save money, reduce human mistakes, increase efficiency, or scale the solutions to very large scales or areas, e.g., for repair, operation, calibration, testing, maintenance, adjustment, cleaning, improving the efficiency, and tracking the Sun.