It is possible to power the Surface 3 (not to be confused with the Surface Pro 3) using a Targus Universal Docking Station BC1.2 USB port (the one with the lightning bolt). To do this, unplug the USB type B cable from the PSU (wall socket) end and plug this into the Targus UDS USB port with the lightning bolt over it. This will power and charge the Surface 3.
To really use the Targus UDS for its features, plug the USB cable that comes with the dock into the Surface 3. Plug-in peripherals, external display(s), Gigabit Ethernet, etc. into the Targus UDS to create a powerful workstations using the Surface 3.