When you gaze up at the stars at night, the distant lights you see are nuclear fusion reactions taking place throughout the universe as atoms fuse together under immense heat and pressure deep in the hearts of stars.
It’s long been hoped that if we could recreate those fusion reactions here on earth, we could unlock an energy source that’s clean, safe, and effectively unlimited.
The catch is that, despite research into nuclear fusion going back nearly a century now, this holy grail of clean energy technology remains frustratingly out of reach.
But we’re getting closer and, by building their own nuclear fusion reactor in Sydney, a group of University of New South Wales undergraduates hope to help humanity harness the power of the sun.
Patrick Burr, the UNSW nuclear engineer who is leading the project, says fusion is an incredible source of energy.
“If we could only get it,” he says.
“We could really solve a lot of the problems that we’re currently facing … with energy security, climate change, universal access to energy, and democratisation of energy.”
That is where Dr Burr’s students come in.
Controlling the engine of a star
Nuclear power plants around the world use fission energy rather than fusion.
It’s a well-understood process: atoms — generally uranium or plutonium atoms — are split apart and the reaction produces energy.
It’s illegal in Australia and we don’t power any part of our grid with it, but when you hear politicians talking about nuclear energy in Australia, they are probably referring to fission energy.
Fusion is different. For a start, it’s usually fuelled by hydrogen and instead of splitting atoms, you squish them together.
In the process of fusing atoms, you produce immense amounts of energy — four million times as much energy as burning coal.
It’s the same reaction that takes place at the heart of stars, but it’s a bit trickier here on Earth.
There’s a long-running joke among fusion scientists that a commercial reactor is about 30 years away.
It’s been about 30 years away since Australian physicist Mark Oliphant first demonstrated nuclear fusion was possible in the lab way back in the 1930s.
For decades, scientists have failed to come up with a viable device, but that’s changing — fast.
The industry is growing quickly, largely from investment overseas, and is slated to be worth nearly $US1 trillion by 2040.
“Fusion is at a pivotal point where it’s growing massively,” Dr Burr says.
“And now it’s the time to get into it, so that we can create a domestic Australian fusion industry.
“At the moment, the big players in fusion are really the US and the UK, and there’s plenty of space to make a mark if we start now.”
Student designed and led
The goals of the UNSW AtomCraft project are simple: design, build, and maintain a small-scale nuclear fusion reactor while becoming the first students in the world to do so.
They’re trying to build what’s known as a tokamak reactor — a donut-shaped device about the size of a small car that uses electromagnets to contain a kind of superheated gas called plasma.
If it works, the students will be able to contain temperatures into the hundreds of millions of degrees — hotter than the furnace at the core of a star.
Safely maintaining those intense conditions is a crucial step towards mastering nuclear fusion.
Anastasia Smyth is studying mechanical engineering and helping to design the system that’ll eventually power the reactor.
She says it’s important we do start engaging in projects like this if we want to master nuclear fusion one day.
“Part of the barrier is that we just haven’t performed a lot of research into these areas yet,” she says.
“Investing money and knowledge at places like UNSW will be crucial in developing nuclear fusion.”
Taking the first steps
The project is in its early stages and right now the students are working on designing the reactor and producing early prototypes of its components.
They’ll need all sorts of bespoke equipment, including microwaves, electromagnets, stainless steel tubes, and high-voltage power units.
There’s a throb of excitement in their laboratory — this is cutting-edge stuff the students are attempting, a hugely ambitious project that could one day help us reach our climate goals.
Physics and mechanical engineering student Marcus Borscz is excited by the challenges ahead.
“It’s crazy,” he says.
“We know it’s crazy, we’ve been told it’s crazy many times, but we’ll give it a go and see what happens.
“We need to start developing skills now because it is going to be our generation that is running these machines in future.”
The team hopes to switch its tokamak reactor on by the end of 2026.
And as for a commercialised fusion reactor? That’s about 30 years away …
Maybe.