I have a low power NAS (~35W) and I want to buy an UPS (uninterruptible power supply) to keep things running. The problem is most UPS for well known brands have an idle power usage (even without load) greater than 20W. It's comprable with the NAS + HDDs + Network equipment....
Do you know any alternative? UPS battery for 10 minutes will be enough. UPS load could be very low < 50 W. UPS software is optional.
For such a small load, you may consider those surge protectors/power stripes with battery backup, e.g. APC Back-UPS 600VA. Or you can take a more DIY route and try those DC UPS circuits if your low-power NAS supports direct DC input, i.e. it has a barrel jack for power.
Indeed they are 😂. It is especially true with the newer gen products. A few years ago these "power stripes with battery backup" had much smaller capacity and fewer capability.
As far as I know the idle power varies from implementations to implementations, especially regarding charging. Also the idle power tends to grow when the battery ages (as the internal resistance increases).
If you are interested in the APC one, it does not hurt shooting them an email asking for the rated idle power usage. From my experience, APC has been pretty eager to respond.
A UPS will have a load. It's got to keep the battery healthy.
They are intended to keep a more vital system up. Generally a NAS is the backup target. And you'd keep the computer is it the target for on the UPS. Maybe the NAS too.
You can probably get away with a desktop UPS. But the power draw is always going to be a factor. The NAS is designed to stay on all the time. So is low power draw.
I will have a power load of 35W 24/7 for years. I'm using the unloaded power consumption as a proxy to measure the UPS consumption/efficiency.
In my case a total power consumption (UPS + 35W load) of 40W will be acceptable, 55W won't.
The UPS has to cycle the battery for its health. This takes power. The 20W will be the recharge.
There is nothing you can do about that. If you DIY your own, without putting battery healthcare. It will fail when you actually need it. And sometimes catastrophically.
Custom build. Intel Nuc i5 + USB 3.0 external Raid 5 case with 3 HDD + Router/Switch. The Intel nuc is really power efficient ~10w. It's comparable with RPi 4 ~5w but 3 or 4 times more performance with hardware video decoding.
Interesting I kept reading USB enclosures like that aren't a reliable setup, at least specifically with unRAID. I've been saving up for a Synology NAS as my "low power" storage for my mini pc cluster.