What is the maximum power provided by PoE? Wikipedia is surprisingly vague on the subject, probably because there are multiple standards. PoE was never intended to power more than just network equipment.
According to that table, the latest standard, 802.3bt Type 4, can provide 71 W to the device at the end of the cable (and inject 100W into the otherside).
Unifi is selling LED panels, that are powered over PoE and controlled over Ethernet.