After a long, seven-year development, an experimental fusion reactor in the UK has been successfully operated in time, yielding the ‘first plasma’: confirmation that all its constituent substances contain hydrogen gas in the plasma phase Can work together to heat up.
This transition – achieved last week by a machine called Mest Upgrade in Kulheim, Oxfordshire – is the core component of a working nuclear fusion reactor, a dream scientists have been trying to realize for decades.
In nuclear fusion, the nucleus of two or more light elements fuses into a heavy nucleus, releasing energy. This is the event that runs in the heart of the Sun, and if we can recreate and sustain similar reactions on Earth, we stand to reap the rewards of clean, boundless, low carbon energy.
Not that we’re quite there yet, but the successful completion of the MAST upgrade and the first test run are a significant milestone in the journey. The original MAST (Mega Amp Spherical Tokamak) facility lasted from 1999 to 2013, and its successors have been in the works since, so it is an important proof of concept.
“We want the UK to be a world leader in fusion energy and to capitalize on its amazing potential as a clean energy source that can last hundreds of years,” UK Science Minister Amanda Solay said in a statement.
“Powering the Mest Upgrade device is an important moment for this national fusion experiment and takes us closer to our goal of building the UK’s first fusion power plant by 2040.”
A fusion reactor needs some kind of equipment to exploit the reactions that occur in the plasma. Tokamax – fusion devices that use magnetic fields to encapsulate the plasma created by the fusion reaction – are one of the leading designs for such equipment.
For a long time, Tocomax employed a donut-shaped configuration, but newer devices such as the Mest upgrade are examples of a more advanced spherical tokam design, which hopes to provide several benefits in terms of efficiency and performance.
The MAST upgrade, run by the Culham Center for Fusion Energy (CCFE), which is part of the UK Atomic Energy Authority (UKAEA), will also need all those benefits. Now that it has been commissioned, the fusion experiment has some very big challenges to solve in the next several years.
The first and most important of these is the exhaust of heat. Fusion reactors create incredible amounts of heat that can damage the reactor’s components. To fix this problem, the mast upgrade would be triaging a new type of exhaust system called the ‘Super-X diverter’, which is designed to reduce the heat and electric load from the plasma leaving particles.
If the diverter is successful, it may offer 10 times heat reduction compared to now, which may be enough to make fusion reactors a cost-effective technology in future power plants.
It’s a big one, but everything about fusion reactors is huge, and the MAST upgrade – despite being a big project that took seven years to build – is only a small part of the whole puzzle.
The device is actually a trial run for another large project, the Spherical Tokamak for Energy Production (STEP), which will be the UK’s first prototype fusion power plant, expected to be finished by 2040.
Meanwhile, what researchers can learn from MAST Upgrad will also inform another large enterprise: the world’s largest nuclear fusion experiment, called the International Thermonuclear Experimental Reactor (ITER).
ITER is currently being assembled in southern France, involving thousands of scientists from over 30 countries. It has been planning for years, and is about five years behind schedule, but when the project is completed (costing around US $ 65 billion is estimated), ITER will be our best chance to show that That the energy produced by nuclear fusion can be harnessed by human hands.
We can get away with searching, but the MAST upgrade is a big step to get us there.
“ITER is the next generation of fusion devices,” explains CCFE physicist Andrew Thornton.
“Mest Upgrade We will support this by providing data from experiments conducted here to instruct how to run that machine in the future.”