The “Dunkelflaute” refers to periods of low wind and solar power production, posing a challenge for grid operators relying on these renewable sources. To address this, a future Ireland powered entirely by wind and solar could utilize overbuilding, storage, interconnectors, and grid upgrades. While current solutions involve fossil fuel plants, better alternatives exist to ensure a reliable power supply during these periods.
Ireland can address Dunkelflaute, periods of low renewable energy production, by overbuilding wind and solar capacity, building more interconnectors to France and Spain, upgrading the grid to prevent curtailment, and implementing long-duration storage solutions like batteries and hydrogen. These solutions, utilizing existing technology, will transform Ireland into a net electricity exporter by 2036, while eliminating fossil fuel power plants. The approach is cost-effective, as renewable technologies are becoming cheaper and more efficient.
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Assumptions:
1. I’m not worrying about variations during a day: solar not producing at night, wind not producing when the air is calm. I’m assuming by the time that we hit 100% renewables we have enough storage to fill the peaks during the day. The concern is Dunkelflaute, when wind and solar production is low for days at a time.
2. I’m not going to worry about the round trip efficiency of storage. For lithium batteries, that’s reasonable, since it’s quite high, around 95% of the energy put into these batteries is available when needed. But the efficiency of pumped hydro and iron-air batteries is significantly lower. But most of the strorage will probably be lithium batteries, so this is probably OK.
3. I’m assuming that generation we add will look a lot like what we have today. For solar that’s probably correct. For wind, the goal is to have 5 GWs of off-shore wind by 2030, and off-shore the wind blows more consistently, so this assumption is a worst case. And for scale, the 5 GWs of off-shore wind means that when the wind is blowing off-shore those turbines will generate enough electricity to power all of Ireland. The power from the land-based wind turbines and solar can be used to charge batteries or exported.
4. I’m going to assume that power will always be available through the interconnectors, even when the Irish grid is suffiering from low wind and solar. In my video on the Celtic Interconnector [point] I looked at the correlations between Ireland, Britian, and France and showed that the correlation between the British and Irish grids wasn’t very high and it’s even lower between the French and Irish grids, so this is a reasonable assumption. For more details I recommend my Celtic Interconnector video.
Form Energy and FuturEnergy Ireland Announce Agreement To Deploy First Iron-Air Battery Storage Project In Ireland
https://formenergy.com/form-energy-and-futurenergy-ireland-announce-agreement-to-deploy-first-iron-air-battery-storage-project-in-ireland/
Battery costs have declined by 99% in the last three decades, making electrified transport a reality
Battery costs have declined by 99% in the last three decades, making electrified transport a reality - Our World in Data
IRENA (2025); IRENA (2024) – with major processing by Our World in Data
Offshore Wind Cost in Japan: CAPEX, OPEX and LCOE Explained
https://deepwind.jp/en/cost-analysis-en/offshore-wind-cost-analysis-japan/
Ireland’s battery storage fleet to grow to 13.5 GWh by 2030
https://www.pv-magazine.com/2024/11/14/irelands-battery-storage-fleet-to-grow-to-13-5-gwh-by-2030/
Europe's electricity storage race: Which countries lead in battery capacity?
https://www.euronews.com/business/2026/05/08/europes-electricity-storage-race-which-countries-lead-in-battery-capacity
Seven days. No wind. No sun. The grid is holding - for now.
https://www.linkedin.com/pulse/seven-days-wind-sun-grid-holding-now-erik-kayser-cvhye?utmsource=share&utmmedium=memberios&utmcampaign=share_via
Electricity production by source, Ireland
https://ourworldindata.org/grapher/electricity-prod-source-stacked?facet=metric&uniformYAxis=1&country=~IRL
The push to lift Ireland's nuclear ban: Going nuclear or nowhere?
https://www.rte.ie/news/primetime/2026/0612/1578039-the-push-to-lift-irelands-nuclear-ban-going-nuclear-or-nowhere/
Timestamp
Dunkelflaute 0:00
Smoothing hourly variations 0:45
Interconnectors 1:30
Capacity vs Average Power 2:05
A future Irish grid 3:00
Bad solutions to Dunkelflaute 6:00
Good solutions to Dunkelflaute 7:00
Channel: Decarbonize!
Published: 2026-06-24
Video URL: https://www.youtube.com/watch?v=iM_n0Ayskns