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Ireland needs to bite the bullet on nuclear energy

Small modular reactors can be mass-produced at relatively low cost and pose less risk

There is pretty much universal agreement in mainline science that global warming poses a deadly threat to humanity and that we must drastically and quickly reduce and then stop burning fossil fuel. The two big non-climate-warming power generation alternatives to burning fossil fuel to release the energy needed to run our societies are wind and solar.

But we also know that the sum of wind plus solar power still leaves us with a shortfall of energy, because both wind strength and solar intensity are erratic. This shortfall is currently met by burning fossil fuels. We hope technological developments will allow us to store excess energy generated when strong winds blow and sunlight is intense, to be used at times when winds fail and/or sunlight is dim.

But we already have access to stable, safe power that doesn’t rely on burning fossil fuel — nuclear power. This should be good news but, despite our enthusiasm for producing doomsday predictions about climate change, little enthusiasm is shown for recruiting nuclear power to supplement wind and solar power to eliminate our dependence on fossil fuels.

Ireland has a close connection with nuclear power through the work of Irish scientist Ernest Walton (1903-1995). Walton, with John Cockroft, split the nucleus of an atom (nuclear fission) at Cambridge University in 1932. Nuclear fission is the basis for nuclear power. Walton and Cockroft were jointly awarded the Nobel Prize in physics in 1951. Until 2015, when Donegal-born William Campbell was awarded the Nobel Prize in Physiology or Medicine, Walton was Ireland’s only Nobel prizewinner in science.


The nuclear power industry traditionally built large nuclear reactors, each big enough to supply the electrical requirements of a city of several hundred thousand inhabitants. Each such reactor is specifically designed for its particular role, costs billions of euros, and takes many years to build with progress bedevilled by objections and delays.

Many environmentalists highlight dangers posed by the long-lived radioactive waste produced by nuclear power. But this danger is often greatly exaggerated as I explained in a previous column. Also, the general public fears nuclear power despite the fact that the nuclear industry has the best safety record of all means of generating electricity. All these factors conspire to intimidate politicians into endlessly postponing the decision to expand nuclear power.

Recent developments in the nuclear power industry allow small modular reactors (SMRs) to be mass-produced at relatively low cost and deployed quickly and safely, making the nuclear option more attractive. The American Nuclear Regulatory Commission recently certified the SMR design for use.

All means of generating electricity have disadvantages — look where burning fossil fuels got us — but the advantages of modern nuclear power swamp the relatively small disadvantages

SMRs are mass-produced in factories and then moved to their site of use. They are simple, less expensive, easier to license and operate safely and less susceptible to serious accidents than the traditional large reactors. Additional SMR units can be easily added to increase capacity if required, for example if new industries moved into the area.

SMR design is new but the concept is not. The US navy has built more than 200 submarine nuclear reactors, most mass-produced in the same manner as the recently certified SMRs, and with no meltdowns or severe accidents.

The navy experience proves that small mass-produced nuclear reactors can be produced and operated safely. Ireland doesn’t need to build traditional large and super-expensive nuclear reactors. SMRs would suit and could be relatively quickly installed.

But endlessly harping on about small risks of nuclear simply makes the ideal the enemy of the good. All means of generating electricity have disadvantages — look where burning fossil fuels got us — but the advantages of modern nuclear power swamp the relatively small disadvantages. If we really believe what we proclaim about the catastrophic consequences of a runaway global warming, then we must act with urgent pragmatism.

Starting up nuclear power in Ireland would greatly help us to meet our greenhouse gas emission targets. In the absence of nuclear power we will depend on burning gas, mostly imported, to generate electricity to supplement wind and solar power for the next 30 years. Nuclear power could save our bacon but if we delay much longer, even that option will be too late to bail us out.

William Reville is an emeritus professor of biochemistry at UCC