A little background: Some years back I learned a very hard lesson about losing power on a RAID array that didn’t have an onboard battery backup. The result was ~7TB of data gone, about 1.5TB completely irreplaceable including old school work and photos. This was a hard pill to swallow and helped me get better about redundant backups and another thing that was especially important: UPS backups, or Uninterruptible Power Supplies.
A UPS is a device which provides power for a short time during a home or business power failure by providing an AC output to whatever is plugged into it. I have several of these scattered throughout my home, including for my desktop and a couple lights around the house which act as emergency lighting using older, smaller UPS devices. My servers are always running UPS backups, but on a big larger scale.