If you use the proper components and allow for expansion later on you can always start with a small system and add to it as you go. It consists of a solar module directly running DC equipment. This could be used on applications such as pumping water or turning on a fan to cool a room when the sun comes out. Inexpensive and simple. Direct wiring to the equipment or appliance.
Power is only available when the sun is out.
Limited types of applications. The equipment or appliance may need some type of voltage regulation to prevent it from being damaged. This is also a very simple type of solar power system. It consists of a solar module, a diode, and a battery. Inexpensive and simple.