Off grid systems can be very simple, or highly complex, depending on your individual needs and the natural resources you have available to generate power. The components of an off grid system can be grouped into three main categories:
We all have access to the sun, so its no surprise that solar is the most common form of renewable energy generation. When light (energy) from the sun hits your solar panels, that energy is converted into electricity. The electricity then travels down the cables from your solar panels, to your inverter. The inverter essentially changes this electricity from an amount that is variable (more sun = more electricity, less sun = less electricity) into a consistent value that we can use for everyday applications, like powering our appliances and lighting.
The same theory applies to the likes of solar and wind power generation. The motion of flowing water or blowing wind will spin a turbine, which converts the energy of movement into electrical energy, which occurs through the rotation of an electrical generator. Similarly to solar, this energy is passed to an inverter, and as the wind or water flows more or less, the inverter regulates the energy so we are able to use it for everyday applications.
But what happens at night when the sun doesn’t shine, or on calm days when the wind doesn’t blow, or when the creek is running lower than normal? This is where battery storage plays its part.
The regulated voltage that is sent out from your inverter not only powers your equipment, it is also used to charge a battery bank. Smaller and simpler systems can have battery charging built into the inverter, meaning there is one box on the wall that does it all. Larger and more complex systems may have two or more boxes on the wall, where dedicated inverters and battery chargers each play a very specific role.
So with your batteries charged, when night comes, or when the wind is calm, or when the creek drops, the electricity flows the other way - That is, the batteries now discharge energy out to the inverter (rather than taking it in to get charged). The inverter does the same job, taking the energy from the batteries, and changing it into a form that we can use for our appliances and lighting.
But what if we go for a week without a sunny or windy day, or what if the creek level drops for weeks at a time? One word - Redundancy.