Mullafarry Battery Storage Project

Mullafarry BESS is a proposed 80MW/160MWh 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, North Mayo.

In April 2025, SSE received a grant of planning permission from Mayo County Council for the proposed development. The approved design includes between 26 and 38 battery units and reflects updates to the previous consent granted in 2018, which had since expired. 

Final delivery of Mullafarry BESS is subject to a final investment decision by SSE.

If approved for delivery, the Mullafarry BESS project would be available to provide battery-stored energy for up to two hours during times of peak demand, helping power homes and businesses across Ireland. It is estimated the BESS would be capable of powering over 75,000 Irish homes for up to two hours at a time*.

The project is also expected to lead to increased local employment during construction and create supply chain opportunities, helping boost the local economy. Once operational, it would also support local investment in Mayo through commercial rates payments.