How Does An Off-grid Solar Electric System Work?

By Author: Peter Clarck
Total Articles: 19
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When solar electricity generation was in its infancy, all installed systems were off-grid types. That is, they were stand-alone systems. The utility providers and homeowners of installed solar power systems were both happy with this structure; both were content with the individual functioning of a system that catered to the goals and objectives of using solar electricity. Homeowners were happy to be independent of utility providers for their supply of electricity, while utility providers were only too pleased to be free from managing complicated homeowner-installed solar systems.
But with changing times and more innovative technologies, off-grid solar systems are becoming a thing of the past. Granted, there are still some die-hard users of off-grid units out there; people who do not trust the reliability of utility providers who are on the grid, or who do not want to take any part in the further depletion of fossil-fueled power, but they are increasingly only operating in isolated places. Still, off-grid system users contend that it is more reliable and less costly when the PV module home solar system ...
... is linked directly to home appliances that use DC current. This is called PV-direct.
Off-grid systems have been found to be of use in applications small and big, distant and near, and range in use from farmers powering irrigation systems for their crops to powering up residences, offices, communities and even hospitals.
An off-grid solar system also requires a backup battery pack that is charged by the DC current generated by the PV modules with a charge controller installed. As with all DC current formats, the electricity generated is converted into AC current through an inverter. Most large, residential solar power systems would need to have a second power source in case of possible electric outage or low output of solar electricity generated (often weather related). This would typically come in the form of a power generator that is connected to the inverter and uses gasoline, propane, natural gas or diesel type fuel.
The inverter can also function like a battery charger. When this is the case, it is called an inverter-charger. Its function differs from the charge controller, which controls the PV modules and battery interaction. The solar purists that we mentioned earlier are typically not pleased with folks who use fossil-fueled powered generators to assist them in the battery charges, as they feel that all solar system activities should depend solely on the solar system provisions -- for better or worse.
When off-grid solar systems are located far away from the grids, one might consider linking up with other renewable energy resources, such as wind-based or hydro-based. This combination of sources synergizes multiple energy resources to provide the best of all worlds for these homeowners. Wind energy is usually available during the mornings and evenings when solar energy is not as active (due to lack of direct sunlight), whereas a micro-hydro energy system provides maximum flow during the winter and least flow during the summer when the sun is at its strongest.

About the Author

Peter Clark is an energy and water management specialist guiding others to save energy and water. Check Solar365.com if you like to know more about solar energy or solar photovoltaic systems .