100W? 5V at 20A? That could mean a quite thick cable.

Seems like USB's answer to thunderbolt. I wonder how different type C usb would be compared to type B or the type of connector that printers etc use?

Ah sure 100W, maybe you want to turn on your incandescent light bulb to see the Keyboard... now speaking sincerely, that can be useful to make practical external graphics acceleration hardware.

100W? 5V at 20A? That could mean a quite thick cable.

Almost. The initial power transfer is 5V at 1.5A. Then the devices can negotiate extra amperage and/or voltage. 100W is max, and won't be available for all devices/cables. The max current values for each voltage look as follows: 5V * 2A = 10W 12V * 5A = 60W 20V * 5A = 100W As you can see, going >10W is tricky, as it would require some changes in laptops which have internals operating at 5V only. The desktops have 12V, so 60W output should be doable, but in both laptops and desktops going >60W won't be easy.

Ah sure 100W, maybe you want to turn on your incandescent light bulb to see the Keyboard... now speaking sincerely, that can be useful to make practical external graphics acceleration hardware.

With USB handshake in USB2.0 device has to deal with 100mA at 5v. Once descriptors are set and handshake is done, host can provide more power if needed. So device has to boot with low power and host can't give 100w without device asking for it.