Fusion won't avert need for climate change 'sacrifice', says nuclear energy expert

But the potentially abundant, if distant, source of sustainable energy could offer hope

Nuclear fusion will not provide an answer to the medium-term "sacrifice" the world population will have to endure to get to net-zero carbon emission by 2050 — the target for keeping average global heating within the 1.5˚C margin.

This is according to scientists making testimony to the UK's Parliamentary Science and Technology Select Committee.

However, the potential source of atomic energy does promise to offer citizens "hope" for sustainable economic expansion in the second half of the 21st century, after the period of climate change sacrifice, said Tim Luce, head of science and operation at ITER, the world's largest fusion experiment relying on magnetic confinement.

ITER is attempting to generate energy by replicating the process that takes place on the Sun, where hydrogen nuclei collide, fuse into heavier helium atoms and release the leftover mass as energy. The experiment hopes to generate sustained fusion reactions and use them to produce limitless clean energy.

Luce told the committee the UK would be unlikely to be able to provide even 10 percent of its electricity from fusion by 2050. "I think the answer is clearly no – we don't have the industrial capacity. We don't have the fuel-making capacity to do that," he said.

Although fusion has achieved significant milestones in the last year, and might show experimental net gains by 2040, Luce agreed with other panellists appearing before the committee that fusion would not be a practical solution to decarbonizing global energy production in a way that could avoid the worst excesses of global warming.

"The question for me about fusion is that it isn't about getting to net zero," Luce said.

"It's about sustaining it into the indefinite future. You're going to ask people to make a sacrifice if you want to meet that goal of net zero by 2050. Are you really going to ask them to continue that sacrifice indefinitely? No, I think you need to provide them a strategy, an exit strategy, that gives them a sustainable growing economy, based on an energy source that is sustainable.

"Otherwise, I think it's going to be a very difficult for governments to ask their citizens to make a sacrifice without some hope. We will provide the hope of a sustainable energy future by fusion," he said.

During last week's hearing, MPs asked experts in nuclear fusion for their estimates for the development of the energy source until it was ready to be plugged into the electricity grid.

Most optimistic was Dr Nick Hawker, CEO at First Light Fusion, who said there were several credible plans for solving the "physics problem" — where the experiment produces more energy than researchers put in — within the current decade.

"I think we will have a fusion power plant — a pilot plant — in the 2030s. And I think we will have a cost-competitive fusion power plant in the 2040s, but at a small scale. We're not going to be suddenly supplying all of our electricity needs from fusion in the 2040s. We still need solar, we still need wind, we still need all [sustainable] sources we can get," he said.

Dame Sue Ion, former chair of the UK Nuclear Innovation Research Advisory Board, said the physics demonstrate net gain in the current decade or the beginning of the next decade. "But when will you get a prototype plant that demonstrates that commercial fusion may be even remotely possible? You're talking about post-2040. If you're talking about the availability of fusion power on the grid, then it is well into the second half of the century, if all the engineering and technical challenges that are yet to come are solved."

The past year has seen a number of significant breakthroughs in nuclear fusion — heralded as a source of plentiful clean energy for more than 50 years.

In January, US scientists published results showing the self-heating of plasma at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in California. Their peer-reviewed paper described how they achieved burning plasma — where the heat from fusing nuclei take over as the main source of fuel heating — across four experiments which each produced more than 100 kilojoules of energy.

A month later, scientists and engineers running the Joint European Torus (JET) facility in Oxford, UK, announced a record-breaking 59 megajoules of heat energy from fusion, more than double the previous record achieved by JET.

Meanwhile, the US government has promised around $1 billion in investment in nuclear fusion over five years.

Nonetheless, the combination of engineering and economics made it difficult to have total confidence in fusion as a viable energy source, Dame Sue said.

"I think there's a difference between confidence that it will work and confidence that it will work 24 hours a day, seven days a week, 365 days a year and satisfy an economic environment in which it's got to live. And my answer to that is, I honestly don't know," she told MPs. ®