Wind Energy Ireland has worked with MullanGrid to track annual constraint levels in Ireland since 2016. See a summary of those maps above.
Since 2016 constraint levels in the north-west, for example, have risen from 2.3 per cent to 11.4 per cent. In the west, it has risen from 0.3 per cent to 8.8 per cent while in the North we are seeing the highest levels of constraints going from 2.3 per cent in 2016 to 14.6 per cent in 2023. Read more about constraints and why they’re a problem.
If you follow the cobalt blue line in the middle of the graph you will see one region in particular has bucked this trend over the last few years.
The south-west solution
The south-west of Ireland, counties – Kerry, Cork, and Limerick – together have 36 per cent of Ireland’s onshore wind capacity and Kerry generates more power from wind than any other county in the country.
But if you look at the graph you can see constraint levels in the region started at 3.3 per cent in 2016, peaked at 7.3 per cent in 2020, but have since fallen to 2.3 per cent in 2023.
How is it that the part of the country with the most wind energy has one of the lowest levels of constraints? Simple, we reinforced the electricity grid.
In recent years EirGrid, the transmission system operator, has successfully delivered more than a dozen important projects in the south-west which have significantly strengthened the local network.
Existing power lines were upgraded, a new power line constructed in west Cork and a major new underground cable in north Kerry. Substations were modernised and new equipment installed. To compare the grid to the road network, we upgraded country lanes to dual carriageways.
These have made the electricity grid in the south-west of Ireland one of the strongest in the country, ensuring that wind farms built there can produce much more of the clean, affordable, power that Irish consumers want.
Fixing the problem everywhere else
To understand how best to fix the problem across the rest of the country it is worth examining this 2023 constraints map overlaying the electricity grid in more detail:
The red lines stretching from Clare to just outside Dublin are 400 kV overhead power lines which can carry an enormous amount of electricity, the equivalent of energy motorways.
The purple lines, of which there are a number around Ireland but note the significant presence in the south-west, are 220 kV lines and cables which can also transport significant amounts of power, like dual carriageways.
But if you look at some of the parts of Ireland with highest levels of constraints – the west, the north-west and the North – you see the grid is reliant almost entirely on 110 kV lines which can carry far less power. This is particularly true of counties like Mayo, Donegal, Tyrone, Fermanagh and parts of Galway and Sligo.
To relieve the congestion in those areas, we need to upgrade our existing grid and to build new high-capacity power lines.
In Shaping Our Electricity Future 1.1, EirGrid’s strategy to reinforce the electricity grid to achieve our 2030 targets, the company sets out proposed upgrades for the 110 kV grid in the north-west which are very welcome and could reduce constraints significantly. These include upgrades on the heavily constrained Flagford – Srananagh, Drumkeen – Clogher, and Srananagh – Sligo 110 kV lines which are urgently needed.
But upgrading the existing infrastructure will not be enough. We need to build new grid as well to accommodate more renewable energy. We need to build a grid that is fit for the 21st century, and that not only addresses today’s constraints, but is future-proofed for Ireland’s clean energy future.
EirGrid proposes to build three new desperately needed power lines. These are:
- North Connacht: A new 110 kV cable connecting Moy substation, just outside of Ballina in Co Mayo, with Tonroe, near Ballaghaderreen, in Co Roscommon. This project has been granted planning permission and it is hoped construction will start soon.
- Clogher – Srananagh 220 kV circuit: A proposed 220 kV overhead line connecting Clogher substation in south Donegal to Srananagh in the middle of Sligo. This new line would greatly reduce constraints in the north-west but there is currently no information on when it will move ahead.
- North-South Interconnector: Arguably the single most important energy project in the State, this is a 400 kV overhead line from Woodland substation in south Meath to Turleenan, south-east of Dungannon, in Co Tyrone. It is critical to a secure electricity supply and there is simply no way to deliver the Climate Action Plan without its completion.
What you can do
We need our elected representatives to loudly and clearly support the reinforcement of our electricity grid and to encourage the various Government departments and State agencies to support designing an electricity grid for a zero-carbon system. It must be understood, defined and supported as a national priority.
Do your part by signing our open letter to Government now.
