NCWQ Environment Report: December 2022

By Pat Pepper, NCWQ Environment Adviser

Summary

Fusion Energy with its environmental credentials may be a step closer to realisation. Two major branches of fusion energy research, Inertial Confinement Fusion and Magnetic Confinement Fusion, are being actively pursued. On 13 December 2022, the U.S. Department of Energy announced a major scientific breakthrough after decades of research, through its Inertial Confinement Fusion  program, using the National Ignition Facility,  at the Lawrence Livermore National Laboratory. More energy was produced from fusion than the laser energy used to drive it¹. This has the potential to provide a new clean and sustainable energy source in the future.

The magnetic confinement fusion approach is being used on the International Thermonuclear Experimental Reactor project which aims to prove fusion can be utilized commercially. While facilities are still being built in France for this collaborative venture involving 35 nations, some successfully steps have been achieved. In recent years, several fusion experiments have reached the important milestone of sustaining plasma temperatures of 100 million degrees Celsius or above, demonstrating an unprecedented ability to replicate conditions found inside the Sun and keep extremely hot plasma trapped long enough to encourage fusion to occur². There are, of course, other scientific and engineering problems but there is hope the sun can be mimicked to provide a limitless clean energy source.

 

Inertial confinement fusion (ICF)

At the National Ignition Facility (NIF) in a controlled nuclear fusion reaction,192 laser beams delivered 2.05 megajoules (MJ) of ultraviolet energy to a tiny fuel pellet containing two hydrogen isotopes to create fusion ignition resulting in 3.15 MJ of fusion energy output – the first time the energy produced exceeded the input¹.  Nuclear fusion, a man-made process replicating the energy that powers the sun happens when two or more atoms are fused into one larger one, generating a massive amount of energy as heat³.

However, the NIF was not designed to demonstrate practical fusion energy. It consumes some 300 MJ of electricity from the grid for each 2 MJ laser shot.  Also whereas NIF’s 1990s-era technology is only 0.5% efficient, modern lasers can get as high as 20%⁴.

The challenges now are to

• produce much more energy from fusion on a much larger scale.
• reduce the cost of fusion so that it can be used commercially.
• harvest the energy produced by fusion and transfer it to the power grid as electricity³.

The scientists admit it will probably take decades before nuclear fusion energy is commercialized. However, fusion promises a virtually limitless form of energy that, unlike fossil fuels, emits zero greenhouse gases and, unlike the nuclear fission power used today, produces no long-life radioactive waste^3,4.

Magnetic confinement fusion, the other branch of fusion energy research,  uses magnetic fields to confine fusion fuel in the form of a plasma⁵.

In southern France, 35 nations are collaborating on the International Thermonuclear Experimental Reactor (ITER) project to build the world’s largest tokamak, a magnetic fusion device designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy based on the same principle that powers the Sun and stars. The ITER is investigating burning plasmas in which the energy of the helium nuclei produced by the fusion reactions is enough to maintain the temperature of the plasma, thereby reducing or eliminating the need for external heating⁶.

In recent years, several fusion experiments have reached the important milestone of sustaining plasma temperatures of 100 million degrees Celsius or above, demonstrating an unprecedented ability to replicate conditions found inside the Sun and keep extremely hot plasma trapped long enough to encourage fusion to occur².

A U.K. experiment sustained fusion energy for five seconds, the longest their magnets could last before the heat melted them. If the ITER can sustain fusion energy for much longer, then commercial-scale machines may be able to start generating fusion in the future⁷.

The ITER is expected to produce 500 MW of fusion power – roughly ten times more power than it consumes.

Australia’s Contribution

At the invitation of the ITER Organisation, the Australian National University together with the Australian Nuclear Science and Technology Organisation, proposes to establish a national fusion program on ITER based around advanced “coherence imaging” systems ⁸.

Also, an Australian laser fusion company HB11 is developing proton-boron fusion technology through a combination of high-powered lasers and magnetic fields².

 

References:

1. llnl.gov/news/national-ignition-facility-achieves-fusion-ignition
2. How far has nuclear fusion power come? We could be at a turning point for the technology (theconversation.com)
3. December 13, 2022 US officials announce nuclear fusion breakthrough (cnn.com)
4. https://physicsworld.com/a/national-ignition-facility-demonstrates-net-fusion-energy-gain-in-world-first/
5. Magnetic confinement fusion – Wikipedia
6. iter.org/proj/inafewlines
7. Nuclear fusion could give the world a limitless source of clean energy. We’re closer than ever to it (cnn.com)
8. ITER Boundary Imaging System – ITER – ANU

 

SDGs 7,9,13,17