If you have a large demand on a single circuit, then you can expand your storage capacity on that circuit by plugging one or more Panel+ or Tower+ into the master Orison Panel or master Orison Tower. The + expandable units cost less by leveraging the power electronics and networking capabilities of the master unit.
For example, a modern, energy efficient refrigerator/freezer uses about one kilowatt-hour per day, so a single master Orison Panel or Tower would keep it going for two days in case of a blackout. If you wanted to ensure longer backup, adding one secondary unit could extend it to four days.
The number you install depends on how much energy you use per day and how many circuits you’d like to maintain operational during a blackout.