Mullafarry Battery Storage Project
Mullafarry BESS is a proposed 80MW/320MWh Battery Energy Storage System (BESS) to be located in the townland of Tawnaghmore Upper, adjacent to SSE’s existing 104MW Tawnaghmore Power Station at Killala Business Park in North Mayo.
In April 2025, SSE received planning permission from Mayo County Council for an 80MW/160MWh BESS at this location. In August 2026, SSE secured a new planning consent to reflect updates to the project, including increased storage capacity and design refinements. The revised proposal would be capable of storing and releasing electricity for up to four hours and would include up to 64 battery storage units.
Mullafarry BESS will provide flexible electricity storage to support Ireland’s power system during periods of peak demand, helping to strengthen security of supply and enable greater integration of renewable energy. The project is also expected to support employment during construction and contribute commercial rates to Mayo County Council, once operational.
Potential capacity
Project news
SSE secures planning consent for revised Mullafarry Battery Energy Storage System in North Mayo
Consent enables SSE to significantly increase the project's energy storage potential to 320MWh.
SSE has secured planning consent from Mayo County Council to revise plans for its proposed Mullafarry Battery Energy Storage System (BESS) project near Killala, North Mayo.
SSE submitting planning application for revised Mullafarry BESS
SSE is submitting a planning application to Mayo County Council to revise plans for its consented Mullafarry Battery Energy Storage System (BESS) project in North Mayo.
The application is seeking approval for an 80MW / 320MWh battery energy storage system capable of storing up to four hours of electricity capacity. This reserve capacity would provide a reliable power reserve available for use by Ireland’s electricity system operator when energy demand exceeds available generation supply.
Project updates
Mullafarry BESS letter
(June 2026)
A copy of our recent letter delivered to local residents
A short film : How does a Battery Energy Storage System (BESS) work?
Contact us
If you have any questions relating to the proposed Mullafarry BESS Project, please contact our Community Liaison Officer:
Email: clo@sse.com