When Ireland declined to build the nuclear power station proposed for Carnsore in Co Wexford in the 1970s, the principal motivation was the minimum size of the plants available at the time.

Both cost and safety were also important issues, but the smallest nuclear plants then available would have been very large relative to the scale of peak demand for electricity; only about one-third of the level now expected by 2030.

Engineers are never happy when the largest generating unit is too big as a portion of peak demand since the lights must stay on if stations or transmission capacity go offline.

There must be a backup available and keeping a large backup unit ready to go is expensive in capital cost and there are ongoing readiness costs even if the spare capacity is not called upon.

Nuclear stations are becoming available at more compact scale and demand is much higher, so this concern about backup costs has diminished.

If nuclear units of around 300 MW were to be available at acceptable capital costs, when peak demand is likely to be 6,000 MW if not more, they would be no larger, relative to the size of the system, than the three coal units at Moneypoint or the bigger gas units currently available to the grid. This leaves safety and cost, but not scale, as the objections to nuclear.

Emerging technologies

According to the Irish Academy of Engineering (IAE) in a report released last Monday, emerging nuclear technologies may become available after 2030, which could be acceptable on both counts.

There is no certainty about the small modular reactor (SMR) technology that is being developed in several countries around the world and the IAE recommend, not that Ireland should dive in and become a launch customer for one of the new designs, that Government should accept the possibility and prepare.

The current policy, enshrined in legislation and to be kept there, is to rule out nuclear generation as an option in Ireland, essentially on the basis that it appeared to be unattractive almost 50 years ago.

This is not to dispute that abandoning the Carnsore plans was a prudent decision at the time – the coal option at Moneypoint turned out to be a defensible decision, at least until concerns about carbon emissions turned opinion and policy against coal.

There have been no significant investments in coal-fired generation in Europe in recent years and instead there are active plans in many countries to resume the construction of nuclear units.

The expectation that new nuclear technologies will make future units cheaper, as yet unproven, is a key motivation. Of course Ireland currently uses, but does not generate, nuclear power.

There are imports from the UK and a new interconnector link to France is under construction – France is a major nuclear generator. The nuclear plant at Wylfa on Anglesey island decommissioned in 2017 is a lot closer to Dublin than Carnsore and the site has been selected for a future unit.

The notion that Ireland was somehow protected from nuclear misadventures by cancelling Carnsore, while there was a plant closer to the capital on Anglesey island, was always optimistic.

Consider the following scenario.

The nuclear industry succeeds in bringing the new technology into commercial production 10 years from now, or even 20.

Moreover, it passes the regulatory requirements on safety and waste treatment of the major developed countries and there is a rush to place orders.

All of these countries have demanding carbon reduction targets and all face growing demand for electricity from battery-powered vehicles, space heating and data centres.

Given the sheer scale of Government ambitions, it is entirely possible that this strategy will not come to fruition because the costs will be excessive

The current policy in Ireland appears to keep nuclear out of the equation, relying mainly on offshore wind, possibly converted to hydrogen, including plans for capacity well beyond domestic needs. No costings for this strategy, including the cost of floating platforms, offshore and onshore transmission and possibly electrolysis plants to convert surplus wind to hydrogen for export, have been made publicly available.

Given the sheer scale of Government ambitions, it is entirely possible that this strategy will not come to fruition because the costs will be excessive.

There are technical challenges too, not all of them resolved. There could easily be a mid-course correction to Ireland’s declared policy should an affordable nuclear alternative emerge, offering always-on power with very low emissions.

Without adequate preparation, the State could find itself unable to choose the emerging SMR technology at a time when there could be long queues of customers and no delivery slots from equipment suppliers.

The IAE recommendation is that the statutory ban on nuclear should be replaced with a policy of agnosticism.

The new nuclear technologies might tick all the boxes, or they might not, and the offshore wind plan is aspirational. The best strategy is to wait and see.