Controlled fusion power could change the world

As the path to a more sustainable future by 2050 becomes even more narrow, the search for carbon-cutting solutions has reached a critical juncture. Partnership among the world’s scientific, government and business communities will be critical to drive change in less than a generation.

Many countries are ramping up renewables such as wind and solar to green their energy systems. But although these sources offer a critical contribution to the global energy mix, they may prove insufficient to meet overall demand.

Experts are excited for reasons beyond its impressive energy-generating potential. Fusion promises an abundant, clean energy source, immune to changes in the weather and without the risk of radioactive by-products. Little wonder that some believe it could solve the climate crisis and end our reliance on fossil fuels for good.

In fusion, two atomic particles merge together, releasing an enormous amount of energy in the process. However, as these particles are positively charged, they naturally repel, rather than attract, one another.

This is not a problem on the sun, where pressure produced by its immense gravitational force is enough to force attraction.

But on Earth, where gravity is less intense, scientists face a steeper challenge. Particles must be subjected to temperatures ten times hotter than those on the sun—a blistering 100m°C—within a tightly confined space to increase the chances of a collision, allowing atomic nuclei to fuse.

In December 2022 the US National Ignition Facility (NIF) carried out an experiment that marked a major turning-point in the fusion story. For the first time, researchers managed to spark a fusion reaction that generated more energy than it used.

Nevertheless, the energy produced in the NIF experiment was minimal. More recent experiments, which have built on this achievement, have still only been able to produce small amounts—enough to run four or five hot baths.

Capturing energy remains a major challenge for researchers. Around 90% of the laser energy used in fusion reactions is lost.

So far, therefore, researchers have been unable to generate and harness fusion energy on a scale that would make it a viable alternative to fossil fuels and existing renewable energy sources.

However, these experiments are only the first step. In the future, larger-scale fusion reactions could produce enough output to power homes, cities or even entire national grids.

So, will this increased interest finally spell the end of the fossil-fuel era? Nicholas Hawker, chief scientific officer of First Light Fusion, the world’s leading inertial fusion company, explains that technological instabilities may continue to impact adoption.

Before it can be considered a practical and commercially viable alternative, fusion must overcome significant engineering challenges and prove its ability to compete with established energy sources.

Fortunately, Ms Budil points out, the increased funding flowing into the sector could accelerate the path to market readiness.

Experts warn that decarbonising our energy supply by 2050 is necessary to mitigate climate change's worst effects. Near-term solutions lie in renewables, conventional nuclear and carbon capture. Yet securing humanity’s future over the long term will require a reimagining of global energy systems.

The stage is set for a new era of clean and abundant power. As technical hurdles fall, fusion reactors will become credible players in tomorrow’s energy ecosystem, in which they are set to play a critical role.