For bar access, the only acceptable forms of ID are Passport, Garda Age Card, and Driving Licence.
If you are 16 or 17 and carry an ID to verify your age on entry, a full-colour photocopy of your in-date passport may be accepted. Blurry, poor-quality, or extremely outdated ID photos will not. (For photocopies to be accepted, it must be immediately obvious it is you. Anything ambiguous will be refused.)