Small Reactors: Big Questions?

Ireland is at the forefront of renewable energy, with wind and solar playing a central role in the electricity mix.

But rising demand combined with the intermittency of renewable generation raises real questions about how the country can securely and affordably source its electricity while cutting emissions. Against this backdrop, nuclear power, and in particular Small Modular Reactors (SMRs), have become part of the conversation.

It’s also the subject of an Energy Law Ireland panel discussion this month. Ahead of that conversation, in the first of two William Fry articles on SMRs, here’s where the debate currently stands.

What problem are advocates of SMRs trying to solve?

Ireland’s electricity demand keeps climbing. Data centres account for more than a fifth of electricity consumption on the island, and continued growth in AI, cloud computing and digital infrastructure will add further pressure, alongside the decarbonisation-driven electrification of heat and transport. At the same time, fossil fuels still supply a substantial share of Ireland’s overall energy needs, according to the Irish Academy of Engineering, and wind and solar (while expanding) remain inherently variable.

Advocates argue nuclear could provide reliable, low-carbon, “always-on” generation to sit alongside renewables, and the idea is gaining traction. The EU adopted an SMR Strategy in March 2026, targeting the first European projects in the early 2030s, and SEAI’s Decarbonised Electricity System Study is examining SMRs among thirty technologies for decarbonising the Irish grid post-2030.

Are SMRs a viable solution?

SMRs are advanced reactors that generate up to roughly 300 MW each (a fraction of the 1,000+ MW typical of conventional nuclear plants). Two features set them apart: components can be manufactured in a factory and assembled on-site, and capacity can be added incrementally as demand grows, rather than requiring a single large upfront investment. Both features make SMRs, in theory, a better fit for a smaller grid like Ireland’s, and their reliance on passive safety systems (gravity, natural circulation, convection) is an additional selling point.

Proponents argue this could translate into shorter build times and lower costs than for a conventional nuclear plant. The Irish Academy of Engineering has suggested SMRs could replace ageing gas plants on a like-for-like basis. But that cost case remains contested: early SMR projects internationally have seen significant delays and cost overruns, and it is not yet established that SMRs will undercut either conventional nuclear or renewables on price.

If not, why not?

Two barriers stand out. The first is technological maturity: SMRs have not yet been deployed at any commercial scale or commercially proven, and uncertainty persists around construction timelines, supply chains and costs. Researchers at UCD Earth Institute note that of the approximately 62 SMR designs worldwide, only 4 reactors are currently operational, and two of these are experimental or demonstrators, the HTR-10 in China and the High Temperature Engineering Test Reactor (HTTR) in Japan.¹

The second is legal and regulatory. Ireland currently prohibits nuclear fission-based electricity generation under section 18(6) of the Electricity Regulation Act 1999 and section 37K of the Planning and Development Act 2000 (restated, but not yet commenced, at section 182 of the Planning and Development Act 2024). The Electricity Regulation (Removal of Nuclear Fission

Prohibitions) Bill 2026, which is proposed by James O’Connor TD, would repeal both provisions. But repeal alone would not be enough. While we have the regulatory capabilities to take on this challenge, Ireland currently lacks the licensing, safety and oversight architecture that a nuclear programme would need, and neither the Programme for Government 2025 nor the Climate Action Plan 2025 currently assigns nuclear a role. Government has signalled that any change would require clear public support.

What would need to change?

The Irish Academy of Engineering has recommended that Ireland begin applying the International Atomic Energy Agency’s (IAEA) Milestones Approach now, building the legal, regulatory, and institutional foundations in parallel with technology maturation, rather than waiting for SMRs to be commercially proven first. This is the three-phase IAEA framework to guide newcomer countries from the initial policy decision through to the construction and operation of their first nuclear plant. Following that framework, preparatory work begun today could preserve the option of SMR deployment in the 2040s; delaying it further pushes that deployment out.

Where next?

So is Ireland’s SMR question really one of technology, or one of political and regulatory will? That’s exactly what “Small Reactors, Big Questions”, Energy Law Ireland’s panel discussion on 22 September 2026, will explore, bringing together political, engineering, system operator and industry perspectives, chaired by William Fry Consultant, Dr Eva Barrett. Please email [email protected] for further details.

Contributed by: Lorraine Kelly

Footnote

1 Dr Muhammad Maladoh Bah, Prof Andrew Keane, “Could Ireland Go Nuclear? Regulatory frameworks, technology choice, and infrastructure issues” (UCD Earth Institute, May 2026).