What is a Grid Tied system with battery back-up (Hybrid)?
The Hybrid system takes advantage of the high efficiency of energy production of the On Grid system, but has a limited load demand battery storage bank to supply power to critical loads in the home like certain lights or a refrigerator. Normally these critical loads do not include the air conditioning unit. Hybrid systems are designed to supply critical loads without the benefit of a solar charge cycle period, referred to as the days of autonomy (3 days is typical). The autonomy period is based on the load demand of the appliances to be operated and the length of time those appliances are to be in operation. Of course the system can be built large enough to power any device as long as cost is not a consideration. If a generator is available to provide recharging of the battery bank, then the days of autonomy can be shortened, as the generator would be called on to offset the loss of access to the sun’s power during extended cloudy periods.
