What “critical loads” do you want to power during an outage?

The installer will review what lighting, appliances, and other items you wish to keep running when the power is out, and will determine how much energy they require. A larger combined load will necessitate a larger battery system to meet the energy needs of your household.

How long can the battery system power “critical loads” without being recharged?

The size of the battery system is also dependent on how many hours or days it would need to provide power to your home. This is without taking into consideration that a solar electric system may also charge the battery during a utility outage. Our Solar + Storage article provides more information about the benefits of pairing a solar electric system with battery storage.

What is your budget?

Although costs continue to decline, battery systems can be expensive, which is why you may want to select a battery system that is sized to power only critical electrical loads when utility power is unavailable. An installer can assist residents in considering all factors as part of properly sizing a battery storage system. When receiving quotes from multiple installers, compare the price per unit of power ($/kW) and the price per unit of usable energy ($/kWh) in each proposal.

What is the battery’s expected lifespan?

A typical product warranty for a lithium-ion battery is about 10 years. If you are pairing your battery storage system with solar, it is likely it will need to be replaced at least once during the life of the solar electric system.

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