This is not the first time that power is up on this forum the last time I measured my NUC7i5 and yes it will work with 12-19V and here are some figures.
I measured my NUC7i5 today it has M.2 SSD for ROCK OS and second SSD for music.
This is with regular 44.1/16 no DSP
19Vdc average 0.57A (10.83W) and peak 1.5A
15Vdc average 0.69A (10.35W) and peak 2.1A
12Vdc average 0.81A (9.72W) and peak 2.8A
Average is during play to Roon endpoint. Peak was during start up.
I have not measured amp usage during a scan for example but if all cores are being used during a library scan I suppose we can see constant use high as peak is in my test.