Wind and solar hybrid type become more and more popular. Wind turbine can produce power at night while no sunshine. Make sure the power is produced continually.
Portable solar system can use from solar panels directly. It support Both DC output and AC output. You can charge phone,use LED light, Small refrigerator,etc.
On grid System also called grid tied system. It has two mode, one is sell full power to grid,another is use the power at first then sell the extra power to grid. All depend on real application