After a long development of seven years, an experimental fusion reactor in the UK was successfully started, obtaining the “first plasma”: confirmation that all its components can work together to heat hydrogen gas in the plasma phase of matter.
This transition – made last week by a machine called MAST Upgrade from Culham, Oxfordshire – is the key ingredient in a functional nuclear fusion reactor, a dream that scientists have been trying to achieve for decades.
In nuclear fusion, the nuclei of two or more lighter elements fuse into a heavier nucleus and release energy. This phenomenon is what happens in the heart of the Sun, and if we can recreate and maintain the same reactions on Earth on a sufficient scale, we will get the rewards of clean, virtually unlimited, low-carbon energy.
We are not there yet, but the successful completion and first attempt of the MAST Upgrade is an important step in the journey. The original installation MAST (Mega Amp Spherical Tokamak) operated from 1999 to 2013, and its successor has been in operation since then, so it is an important proof of the concept.
“We want the UK to be a world leader in fusion energy and to harness its amazing potential as a source of clean energy that could last for hundreds of years.” stated UK Science Minister Amanda Solloway said in a statement.
“Starting the MAST Upgrade is an important moment for this national fusion experiment and brings us one step closer to our goal of building the UK’s first fusion power plant by 2040.”
“ITER is the next generation of fusion devices,” explains CCFE physicist Andrew Thornton
A fusion reactor requires some kind of device to capitalize on the reactions that occur in plasma. Tokamaks – circular devices that use magnetic fields to contain the plasma created by the fusion reaction – are one of the top projects for such a device.
For a long time, tokamaks have used a donut-shaped configuration, but newer devices such as MAST Upgrade are examples of more advanced spherical tokamak design, which is expected to offer numerous efficiency and performance benefits. .
The MAST upgrade, which is operated by the Culham Center for Fusion Energy (CCFE), which is part of the UK Atomic Energy Authority (UKAEA), will also need all these benefits. Now that it’s operational, the fusion experiment has some pretty big challenges to solve in the next few years.
The first of these is heat dissipation. Fusion reactors create incredible amounts of heat that can damage reactor components. To resolve this issue, MAST Upgrade will test a new type of exhaust system called “Divergent Super-X”, Designed to reduce the heat and energy loads of particles leaving the plasma.
If the entertainer is successful, it could offer a ten-fold reduction in heat compared to what has been possible so far, which could be enough to make fusion reactors a cost-effective technology in future power plants.
“MAST Upgrade will provide data from the experiments we are doing here to indicate how to run that car in the future”
The device is actually a test for an even bigger project, Spherical Tokamak for Energy Production (STEP), which will be the first prototype fusion power plant in the UK, expected to be completed by 2040.
Meanwhile, what researchers can learn from MAST Upgrade will also inform another massive adventure: the largest nuclear fusion experiment in the world, called International Thermonuclear Experimental Reactor (ITER).
ITER is currently assembled in the south of France, involving thousands of scientists from over 30 countries. It has been planned for years and is about five years late, but when the project is completed (estimated to cost around $ 65 billion), ITER will be our best chance to show that the energy produced through nuclear fusion it can be capitalized on by human hands.
We may be years away from discovery, but MAST Upgrade is a big step forward to get there.