Solar power continues to hit new milestones in Ireland, setting an all time monthly high for electricity generated in May.

173,163 MWh (megawatt hours) of electricity was produced from grid-scale solar last month, making up 6.5% of all electricity generated for the month.

This is the highest ever production level recorded for solar power in Ireland, more than twice as much as in the same period two years ago.

In comparison, just 2.7% of electricity came from solar power in May 2023 accounting for 71,731 MWh of power generated.

There were also a number of new peaks for grid-scale solar activity for a one-minute period, reaching 755 MW at one point on the 17th of May 2025, beating the record of 752 MW set two days earlier on 15 May.

The previous record of 750 MW was recorded on 24 March 2025. This followed a new peak wind power record on the grid set in February.

Diarmaid Gillespie, Director of System Operations at EirGrid, said, “While onshore wind remains the prominent renewable source of electricity in Ireland, solar power has become a notable feature of the Irish power system over the last two years in particular”.

In total renewables accounted for 32.5% of electricity generation last month according to provisional data from Eirgrid.

The majority of this came from wind, which accounted for 22.5%, while 6.5% came from solar, and the remainder of renewable generation came from other sources including hydro and biomass.

Diarmaid Gillespie added, “We may see further records being reached over the coming summer months. We also continue to see electricity imports contributing significantly to our fuel mix in meeting electricity demand.”

Looking at the rest of the fuel mix, gas generation accounted for 39% of the electricity produced, with 22.8% being imported via interconnection, 4.6% coming from coal, and the remaining 1.1% from other sources.

Overall electricity system demand was 2,671 GWh for May 2025, similar to 2,679 GWh in May 2024.

Diarmaid Gillespie said, “Operating a power system with electricity generated from variable renewables such as wind and solar, mixed with conventional generation, is complex and technically very challenging.”

“To maintain stability on the grid, EirGrid engineers need to be able to adjust to and meet fluctuating energy demand with supply at all times.”

Ireland’s electricity grid can currently accommodate up to 75% of electricity being generated by renewables at any one moment. This is known as the system non-synchronous penetration (SNSP) limit.

Eirgrid is investing in upgrades to the electricity network to increase this limit and enable the connection of further generation sources to maintain a secure and reliable power supply.