Yes, planning permission generally stays with the land rather than the applicant, meaning it remains valid for any subsequent owner as long as it hasn't lapsed or been implemented in a way that exhausts it. Permissions usually last five years from grant unless extended, after which they cease to be capable of being acted upon.
Planning permission in Ireland runs with the land, not with the individual applicant, so a change of ownership does not itself cancel or require renewal of the permission. This is one reason why permitted but unbuilt sites can be marketed and sold with the benefit of an existing, unexpired permission, and why buyers often place value on land that already has permission attached.
However, this benefit is time-limited. A standard planning permission typically has a default life of five years from the date of grant, within which substantial works must commence, and it may lapse if not acted upon in that period, unless an extension of duration has been sought and granted by the local authority. Once lapsed, the permission can no longer be relied upon and a fresh application would be needed.
It's also possible for a permission to be effectively "used up" if the development it covers has already been substantially completed, meaning a new owner inherits the completed structure rather than any remaining unused development rights. Checking the permission's status, commencement notices, and any extension of duration applications is important before assuming it remains available in full.