The Sparc nuclear fusion reactor will work (at least on paper)

A series of studies prove that Sparc, MIT's nuclear fusion reactor, is very likely to work. But it will still take a long time to see the world of zero-emission energy revolutionize

(Photo: Mit) We have been trying for years: to be able to imitate the way the Sun and the stars produce energy. A very difficult task, despite the numerous projects underway around the world. But today, to give us new hope, are the researchers of the Massachusetts Institute of Technology (MIT) and the startup Commonwealth Fusion Systems, who have just laid the physical and theoretical foundations for Sparc, a new nuclear fusion reactor which, according to seven studies just published in the Journal of Plasma Physics, could finally work. And help us, therefore, in the fight against climate change.

We remember that nuclear fusion (not to be confused with nuclear fission) is considered a fundamental tool to be able to tackle climate change. A fusion power plant, in fact, would not need to burn fossil fuels and would not produce greenhouse gas emissions and radioactive waste. In particular, the fusion reaction consists in the fusion of different hydrogen isotopes at very high temperatures (hydrogen loses electrons and forms a plasma of ions) to produce immense amounts of energy (used, for example, to produce electricity) and helium atoms (reaction waste), without the need for additional energy inputs.

The construction of Sparc should begin as early as next spring and last for the next three or four years. Then, tests and experiments will follow and, if successful, we will start with the construction of a power plant capable of using fusion energy to generate electricity starting from the next decade. A very ambitious calendar, therefore: among the objectives of Sparc, the researchers specify, there is also that of being able to carry out nuclear fusion in time so that it can play a role in mitigating global warming. “We are really focused on getting to fusion as quickly as possible,” explained Bob Mumgaard, founder of Commonwealth Fusion Systems.

Confronted with the Iter project, the result of a huge international collaboration and under construction since 2013 in France, Sparc would be much smaller and much less expensive. However, it would use the same type of device: a tokamak, or a special donut-shaped reactor within which the fusion reaction takes place. Since the plasma cloud is extremely hot, it must be confined by means of magnetic fields: for this, Sparc will exploit an innovative electromagnetic technology that uses the so-called high temperature superconductors capable of producing a much higher magnetic field (and consequently the plasma will be much smaller).

"Our research confirms that the project we are working on is very likely to work," explained Martin Greenwald, deputy director of MIT's Plasma Science and Fusion Center and a leading scientists involved in the project. "If we can overcome the engineering challenges, this reactor will perform as planned." But the obstacles to building such a reactor are enormous. And some experts, while enthusiastic about it, have already proved dubious, especially as they believe the proposed timetable is not realistic at all.