Up to three quarters of the electricity flowing onto the Irish grid at any point in time can now come from variable renewable sources, according to a study by national grid operator EirGrid.
The Ireland and Northern Ireland power system is the first in the world to reach this level, overcoming “major technical challenges” associated with integrating electricity from wind farms, solar farms and interconnectors that link it with other countries.
EirGrid had previously imposed a cap of 70% on the amount of variable renewable generation on the grid at a given time.
This has now been raised to 75% following a successful 11-month trial.
The grid successfully ran at between 70% and 75% variable renewable energy for a total of 232 hours during the trial period.
There were several new all-island wind energy records set during the 11 months, including the current record of 4584MW on 5 February 2022.
Wind, solar and interconnectors have very different technical characteristics to conventional fossil-fuel powered generation.
This creates challenges in maintaining the stability and security of the power system forcing EirGrid to limit the amount of variable renewables on the grid.
Liam Ryan, EirGrid group chief innovation officer, said: “This is a hugely significant milestone and a critical step in the decarbonisation of the electricity sector on the island of Ireland.
“It marks the culmination of an 11-year programme of work by EirGrid and its partner SONI in Northern Ireland, as well as by stakeholders from right across the industry.”
Since the inception of the programme in 2011, EirGrid has increased the limit from 50% to 75% in a series of five steps.
Work will now begin on increasing the figure to 95% by 2030 in order to achieve Government renewable energy targets.
This will be achieved through the delivery of EirGrid’s Shaping Our Electricity Future programme of work.