Grid ownership
The Electricity Supply Board (ESB) is the electricity transmission asset owner (TAO) and the electricity distribution asset owner (DAO) in Ireland. This refers to onshore assets. Information about compliance and enforcement can be found here.
Ownership of the offshore transmission system will rest with EirGrid at all stages of the phased transition, regardless of whether the grid has been planned and developed by the individual renewable energy projects or the TSO. Eirgrid is the Transmission System Operator (TSO) in Ireland: https://assets.gov.ie/134847/bd02ef78-75b2-4174-a160-4946c69a7b5d.pdf
Island interconnection
Yes
Island relevant TSOs and DSOs
EirGrid (TSO) and ESB Networks (DSO)
Development of electricity grids for RES integration
The Commission for Regulation of Utilities [CRU] is committed to the ongoing development of strategic policies toward energy security, driven by a low-carbon approach
Electricity Connection Policy: https://www.cru.ie/publications/27384/
Enduring Connection Policy Overview: https://www.eirgridgroup.com/customer-and-industry/becoming-a-customer/generator-connections/enduring-connection-polic/
Enduring Connection Policy Decision Paper: https://cruie-live-96ca64acab2247eca8a850a7e54b-5b34f62.divio-media.com/documents/CRU202326_Enduring_Connection_Policy_ECP_2.4_Decision.PDF
Specifications for islands, isolated grids, microgrids, local grids, etc.
Irish legislation does not specify this topic. The current legal position in Ireland is that only the ESB (Distribution Asset Owner (DAO) and Transmission Asset Owner (TAO)) can own an electricity distribution or transmission system. As such, the supply of electricity from the generation site to the demand user takes place on the ESB-owned National Electricity Grid.