Consumption in Watts:
Only power supply plugged: approx 0.14
Switch on, 0 Cable: approx 0,64W
Switch to, 2 cable: approx 1,21W
Switch on, 3 cable: approx 1,64W
Switch on, 4 cable: about 1,71W
In the test for each inserted cable was also the appropriate device.
Consumption rose although not when a cable was connected, however, the power turns off.
The included power supply is very small and connects the switch through a long and thin cables.
The switch is also common practice to build compact, there are small such as the Netgear GS205 (with somewhat higher consumption).
Netgear GS205-100PES Gigabit Switch (5-port)