Solar off grid power system are used where uninterrupted power supply is required . Such systems are used in locations where power availability is of utmost importance. Such systems include a battery pack which provides power during power outages. Solar Off grid power systems do not result in higher charging costs since the charging is mainly done from the solar panels installed with the unit. Although the Solar inverters installed do have the facility to enable charging from the power line as well.
The Solar off grid power systems do result in lower overall power bills as power supply is taken from the inverter once a certain charge is stored within the batteries. However for reducing power costs it is highly advisable to consider having a Solar on grid power system installed instead.