This system has a battery and additional controls, which can slow down the electricity meter and charge the back-up batteries for storage, to be used at night.

This is basically the same type of system used in homes that are completely off-grid. Depending on the size of this system and the appliances or devices requiring power, it can support an entire home or just the items that are considered the most necessary during power failures. These systems are more expensive because of the battery reserve capacity and additional controls required in the system.

Typically, depending on the amount of battery reserve, these systems cost about 50% or more than a comparable Grid-tie system. However, in areas with frequent power failures (as in South Africa), these fully automatic, silent solar powered backup systems are a must.