Site details

Energia’s first grid-connected battery energy storage system (BESS) is now operational on our Castlereagh site, just outside Belfast. The facility is located near the existing Castlereagh substation and utilises the local electrical infrastructure to connect to the grid.

The development is made up of a series of containers or cubes, each containing rechargeable battery units, together with a transformer compound, security fencing, CCTV and lightning mast. The on-site 110 kV substation is operated by NIE. It is directly connected to the Castlereagh substation and transmission network.

The battery facility will help the stability of the electricity grid during times of high renewable generation by storing electricity, which can then be released back into the system very quickly when needed.

Scheduled maintenance

The Castlereagh battery storage facility is now operational - with some outstanding works on site still to be completed.

We will continue to post maintenance updates here.

What is battery storage?

Renewable energy is now supplying more than 40% our annual electricity needs in Northern Ireland.   Battery storage facilities like Castlereagh will help match intermittent generation from renewable energy sources, such as wind and solar, with the peaks and troughs of real time electricity demand. 

The facility will absorb and store electricity when a surplus is available and release it back into the system when electricity demand exceeds supply.