How many hours your UPS battery will last, or what battery size you need for the backup you want.
How this works
Backup hours = battery volts x Ah x usable depth x inverter efficiency / load watts. Lead-acid and tubular batteries should only use about 50% (usable depth 0.5), lithium (LiFePO4) about 90%. Inverter efficiency is about 85%.
Questions people ask
How do I use the UPS Inverter Battery Backup tool?
Fill in the fields, starting with “I want to find”, “Load running in load-shedding” and “Battery bank voltage”, and change any other options that match your home. The answer, a drawing and practical tips update as you type, and the Copy link button saves your numbers in a link you can share.
Is the UPS Inverter Battery Backup tool free?
Yes. The UPS Inverter Battery Backup tool is free, with no sign-up, and works on phones, tablets and computers. The results are estimates to help you plan, so check with a qualified professional before structural, electrical, gas or plumbing work.