Backup Power is a system that connects to electricity sources, typically solar panels and the electric grid, to store excess power and return it to your home when you need it, generally because of a power outage during an emergency. In most cases, your backup power supply will come from a generator or a battery. Today’s solar batteries are also intelligent energy management systems that can optimize your home’s energy usage to take advantage of utility time-of-use plans or to ensure that your electric car is charged with solar power.