Flashlight batteries and cases of water are selling out, and gas tanks are being filled as worried residents try to picture their lives in the dark for what could potentially be days.

But there is an alternative. Home and business owners who make their own energy from the sun and store it in a solar battery don’t have to rely solely on an increasingly unstable conventional grid. With a solar battery system, you can store solar energy for use at night, during an outage, or to avoid peak demand charges.

Castaways recently announced Equinox Storage—the first all-in-one residential solar plus storage system designed, engineered, and warranted by one company—to provide seamless backup to power essential appliances and more.

This means that when the grid power goes out, your lights and refrigerator can stay on, and you’ll still be able to charge your cell phone or laptop.

Depending upon the size of the battery storage system, your settings, and several other factors, you may be able to store enough electricity to power your entire house for a limited period of time.

Check out this infographic for an easy-to-understand visual explanation of how a solar storage battery works.

How Equinox Home Solar Batteries Work During a Power Outage

The Equinox Storage battery consists of two boxes that are best installed inside a garage but can be placed outside as well. The main unit, 21 x 62 x 13.5 inches, contains a battery microinverter and either one or two batteries, depending upon your needs, to store up to 13 kWh of energy. For larger homes, multiple units can be connected to reach 26kWh and have more stored energy.

There is also a small controller box, known as the Hub Plus, which functions as the brains of the system. With the Hub Plus, you don’t have to worry about fumbling around your garage in the dark during a power outage to switch to battery power. The Hub Plus takes care of that for you. The battery storage system connects to and powers a set of backup breakers that are connected to the appliances and outlets that you want to power during an outage.

Since you’ve already chosen which appliances or how much of your house you want to power in a blackout, when the power goes out, the Hub very quickly switches to solar battery power. It’s that simple.