It sounds easy – there's a power cut and so you just run your home off the battery instead. Sadly, it's a little trickier than that, so here are the key things you'll need to consider. The main complexity with using batteries for backup power is that they have to comply with strict safety requirements. If there's a power cut,. You'll need to decide what percentage of your storage capacity you want to reserve for backup. This means you keep your battery partially full with your emergency electricity. Most people. Home batteries have an integrated inverter that produces AC power for use in the home. The higher the rated power output of the battery inverter, the higher instantaneous power can be delivered to appliances at any one. Instead of separating critical loads, in some situations it may be possible to fit a physical changeover switch. In the event of a power cut you would turn off the non-essential loads and. If you do try to use more power than the battery inverter can provide, you might trip the battery inverter, and still end up with no power during the power cut! And of course, as the transition from grid to battery is smooth, you.