That Thunderbolt port can charge the device, but HP includes one of its proprietary (and clunky) chargers in the box that connects to the Elitebook x360 using the traditional, circular port.

while the legacy ports (and charger) will keep the IT department happy that it can mix and match the Elitebook without worrying too much about peripheral support issues. The HP Elitebook x360 is a ...

All of the modes let you use the HP ... the EliteBook x360 (the same cord transmits DisplayPort signals and charges the laptop simultaneously), or you can use another laptop's USB-C charger ...