Today I published a video detailing my testing of three new Raspberry Pi HATs—these HATs all add on PoE+ power and an NVMe SSD slot, though the three go about it in different ways.
You can watch the video for the full story (embedded below), but in this post I'll go through my brief thoughts on all three, and link to a few other options coming on the market as well.
Power over Ethernet lets you run both power and networking to certain devices through one Ethernet cable. It's extremely convenient, especially if you have a managed PoE switch, because you get the following benefits:
I have used the Raspberry Pi PoE and PoE+ HATs for years now, allowing me to have 4 or 5 Raspberry Pi per 1U of rack space, with all wiring on the front side. I also use PoE for cameras around my house, though there are dozens of use cases where PoE makes sense.
The Raspberry Pi, since it only requires 3-10W of power, is an ideal candidate for PoE, assuming you can find a HAT for it.
The PoE+ HAT powers a Raspberry Pi 3 B+ or 4 model B over a single Ethernet cable, allowing you to skip the USB-C power adapter, assuming you have a PoE capable switch or injector.
Unfortunately, I would recommend the original PoE HAT over the newer PoE+ HAT for most users—though Raspberry Pi have redesigned the HAT slightly and it's more on par with the original, though hard to distinguish which model you're getting. (Updated mid-2023)
For more background on PoE in general, and a bit more detail about the board itself and my tests, please watch my video on the PoE+ HAT—otherwise scroll past it and read on for all the testing results: