We track 588 hotels in Taiwan, 588 of which have had a research pass. Across the 14 with a coffee setup on record, the most common in-room system is the capsule machine.
Mains supply here is 110V at 60Hz, using plug types A, B.
A plug adapter changes the shape of the pins and nothing else. A single-voltage kettle from a 120V country will not work safely on a 230V supply no matter which adapter you use — check the label on the appliance for a dual-voltage range before you pack it. More on travel kettles and voltage →
What to expect in the room
Kettles are standard. Drip bags and instant sachets are common in the room, and convenience-store coffee is good and everywhere. Arriving with nothing is a perfectly sound plan.