POE, POE+ vs UPOE: What’s the difference?

PoEPoE+UPoE (Universal PoE)
IEEE 802.3af standardIEEE 802.3at standard. It is backward compatible with 802.3af which means POE device can operate normally when connected to POE+ switch port.Cisco Proprietary
PoE uses 2 pair twisted cable.PoE+ uses 2 pair twisted cable.UPoE uses 4 pairs of twisted cable.
Provides 15.4W maximum power to each switch port.Provides 30W maximum power to each switch port.Provides 60W maximum power to each switch port.

You need to calculate the power requirements for all the powered devices that you plan to connect to switch. Also be careful while laying longer network cable, as some power is lost over the length of cable.