Fusion energy: What does the recent breakthrough by scientists in California mean?

17 Dec 2022

Dr Pádraig MacCárthaigh of School of Physics, UCC wrote an article for the Irish Examiner on the recent break-through in fusion energy research in California.

"The ultimate goal of this research is to construct fusion reactors that would provide electric generation capacity to ensure a stable supply in a post-fossil fuel world where most power will be generated by inherently volatile renewable energy sources."

"In the quest for fusion-based electric power generation, the most easily achieved fusion reaction, involving two heavy hydrogen isotopes, deuterium (D) and tritium (T), produces no immediate radioactive waste. Most of the fusion energy is carried by energetic neutrons, however, and these induce a low level of radioactivity over time in the surrounding structures, but it is far less concentrated than fission waste products, and decays on far shorter timescales (a hundred years versus many tens of thousands of years)."

"Since 1958, fusion energy research has focused on trying to demonstrate that a net energy-producing fusion reaction on Earth is possible in practice. Initial results were far from promising, with output fusion energy around 0.01% of input energy.

Advances since then have progressed slowly but steadily, culminating in the achievement of 60% output fusion energy for several seconds in 1997 at the Joint European Torus, the largest operating MCF fusion experiment in the world, which is located outside Oxford and to which a number of Irish scientists and engineers have made significant contributions."

"Further progress in achieving ‘break even’, where fusion energy output equals or exceeds the input energy has been slow in the intervening period. That is, until the recent ground-breaking announcement by the National Ignition Facility (NIF) at California’s Lawrence Livermore Laboratory, the globally leading centre for ICF research, that a fusion reaction in the laboratory generated excess fusion energy for the first time."

"the breakthrough at NIF is a landmark advance in the pursuit of the holy grail of a safe, clean and reliable carbon-free source of power generation. It can’t come soon enough to slow down, and ultimately arrest, the ominous and accelerating rate of climate change caused by carbon emissions that result from the unabated consumption of fossil fuels."

Read the full article here: Fusion energy: What does the recent breakthrough by scientists in California mean? (

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