What would it take? The question for Ireland is not whether to build a nuclear plant. It is whether to keep the option open.
In the first of two William Fry articles on Small Modular Reactors (SMRs), we set out where the debate stands. On 22 September 2026, Energy Law Ireland’s panel discussion, “Small Reactors, Big Questions”, chaired by William Fry Consultant, Dr Eva Barrett, tested those questions against political, engineering, system operator and industry perspectives. The starting point was sobering: SMR technology is still maturing, the statutory ban remains in place, and the regulatory framework is lacking. So the useful question is what Ireland should do now if it wants nuclear to be a real choice in the 2040s.
Can Ireland’s grid take a reactor?
Only at the right scale. Ireland runs a small, isolated system, with EirGrid forecasting a median peak demand of 6,044 MW for winter 2025/26. A conventional 1,000+ MW reactor would equal a sixth of that peak, such that any sudden loss of that volume of power would be a severe shock to the system. The IAEA flags this exact risk for small systems, and the rule of thumb is that no single unit should exceed roughly 10% of grid capacity. That makes SMRs, at up to around 300 MW each, the only credible nuclear fit.
What happens when the wind drops?
Ireland’s renewables success has a weak spot: dunkelflaute, the long, dark, windless spells of winter. EirGrid’s own winter outlook identifies periods of low wind and low interconnector imports as the most likely trigger for system alerts. Today, gas fills that gap. Advocates argue that firm, low-carbon nuclear power could do the same job without emissions; others point to storage, interconnection, and demand flexibility. Batteries are growing fast, with record discharge of 502 MW in December 2025, but they cover hours, not weeks. A key point was that the debate should focus on resilience over the entire winter, not just installed capacity.
Is waste a solvable problem?
Yes, but only if it is planned from day one. The panel was clear that the question of radioactive waste cannot be left until a reactor is running. It must shape site selection, licensing and funding from the outset.
Finland shows what that looks like. Posiva began building the Onkalo deep geological repository in 2004. In August 2026, Finland’s safety regulator, STUK, found no radiation or nuclear safety obstacle to granting an operating licence, putting Onkalo on course to be the world’s first operating final disposal facility for spent fuel. That result reflects decades of clear regulation, local consent and political consistency.
For Ireland, a waste regime would need rules on handling, transport, interim storage and final disposal, backed by funding and liability arrangements. That is a major legislative project in its own right, spanning environmental, planning, health and safety and treaty law.
Do the numbers add up?
Not yet proven. The factory-built, modular promise has still to be delivered at scale. Vendors such as Rolls-Royce SMR say standardised, factory-built units will bring greater cost and schedule certainty; the first projects will show whether that holds. For Ireland, the test is whether SMRs can complement, rather than compete with, the substantial investment already committed to wind, grids and storage.
What would Government need to do?
As set out in our first article, the starting point is to repeal the prohibitions in section 18(6) of the Electricity Regulation Act 1999 and the planning code. The Electricity Regulation (Removal of Nuclear Fission Prohibitions) Bill 2026 would do that, and Fianna Fáil’s parliamentary party agreed in May to support it. The Taoiseach has said Ireland should not have a statutory bar on considering nuclear power, while the Green Party argues nuclear power would not lower household bills for at least 15 years. But repeal only removes the barrier; it does not build the pathway. Ireland would also need legislation on siting, construction, operation, decommissioning, waste and nuclear liability, and an independent nuclear regulator to oversee it all.
What can Ireland learn from others?
Finland shows that long-term waste disposal can be delivered through patient planning. Poland shows how long the road is for a nuclear newcomer. Its first plant, three AP1000 units at Lubiatowo-Kopalino, lodged its construction licence application in March 2026, with first concrete expected in late 2028 and commercial operation from 2036. When the Polish government approved the project in 2023, the first unit was pencilled in for 2033. The UK shows the value of a state-backed delivery body: Great British Energy – Nuclear has contracted Rolls-Royce SMR to develop three reactors at Wylfa. France is a reminder that nuclear and renewables can share one system.
The common thread: every programme began with policy commitment and institution-building long before any reactor was ordered.
Where next?
Keeping the nuclear option open does not mean committing to build. It means doing the groundwork now: legislative reform, grid reinforcement, regulatory capability, a waste strategy and close monitoring of first-of-a-kind SMR projects abroad. The IAEA Milestones Approach, which the Irish Academy of Engineering has urged Ireland to adopt, already provides the roadmap. Poland’s timeline suggests that groundwork takes a decade or more. If Ireland wants SMRs to be a genuine choice in the 2040s, the clock is already running.
Note: The Energy Law Ireland panel discussion was held under the Chatham House Rule. The views summarised in this article are not attributed to any individual speaker or organisation.
Contributed by: Lorraine Kelly
