Private companies engage in nuclear fusion

At present, all of theenergy nuclear world (including the 56 nuclear reactors French) is based on the nuclear fission process: a nucleus ofuranium is split into smaller particles, releasing energy. But there is another way to produce nuclear energy: fusion.

It is a process in which two atoms come together to form a heavier atom; it occurs in particular in the heart of the stars. Research to master fusion such as energy source began in the 1950s, but the prospect of its industrial use remains remote.

Yet while it has long been a purely public field of research, a growing number of private actors have recently entered the field, promising functional reactors at very short time scales.

Why nuclear fusion?

The potential benefits of fusion are countless: very low emissions of CO₂, no Radioactive waste high activity and long life (short-lived waste is still formed), an intrinsically safe process because the reaction stops almost instantly in the event of a problem (a accident Of type Chernobyl is impossible). In addition, the combustible is very dense (one gram of fuel contains as much energy as 11 tonnes of coal) and abundant enough to last for thousands of years (fuels can be extracted from Seawater).

On the downside, fusion requires extreme conditions, a temperature above 100 million degrees in particular. Ten times more than the core temperature of the Sun !

There are in theory different methods to achieve the conditions necessary for the merger. In all cases, inducing the fusion process requires heating and then maintaining a mixture at a very high temperature (this is called plasma) and therefore investing energy. The challenge of the fusion reactor is therefore to produce more energy than that necessary for its operation: we speak of amplification gain.

However, until now, an amplification threshold greater than 1 (we produce more than we spend) has still not been reached. Current research has only made it possible to achieve an amplification gain of 0.7, that is to say that per 100 joules of energy invested, fusion produces only 70. Not yet enough for practical use.

Public research

This record was set in 1997 by the tokamak JET in England, and was tied in August 2021 at National Ignition Facility to USA.

In reality, a machine like JET is too small and too little powerful to achieve an amplification gain greater than 1. To exceed this threshold, we had to launch in 2006 the Iter project, fruit of the collaboration of 35 countries. Currently in construction in Cadarache (Provence-Alpes-Côte d’Azur), Iter is not intended to produce electricity: it is a pure scientific experiment. Its goal is – among other things – to demonstrate the feasibility of fusion, targeting an amplification gain of 10. The first fusion experiments are scheduled for 2035.

For the industrial demonstration phase, each country draws up its own plans. L’Europe plans a reactor producing electricity in the 2050s. South Korea and Japan work on their own concepts. These projects have in common electrical powers of several hundred megawatts, and electricity production after 2050. This corresponds to the electricity consumption of around 1 million. French.

Other countries are trying to go faster. the United KingdomI recently launched the Step project (Spherical Tokamak for Electricity Production) which aims to develop an operational reactor in the 2040s. China pursues with CFETR an ambitious program aimed at demonstrating the production of electricity and tritium in the 2040s. In the United States, a report submitted in 2020 to the Academy of Sciences recommended setting up a program targeting a reactor in the 2040s .

The emergence of private companies

In recent years, private companies have entered the race and aim to strongly accelerate the development of nuclear fusion. Relying on highly qualified teams (CFS is thus the result of MIT), these initiatives have more aggressive and daring approaches than public research.

If we often talk about start-up, some of these companies are more than 20 years old, such as TAE founded in 1998 or General Fusion founded in 2002. In 2021, there are more than 25 private companies launched in the merger race, ie 4 times more than in 2008. Even France has a start-up, Renaissance Fusion, founded in 2019.

Those companies are mostly financed by investment funds, and sometimes backed by big names such Jeff Bezos (General Fusion) and Bill gates (CFS). Two of them, Helion Energy and Commonwealth Fusion System (CFS), recently distinguished themselves by announcing fundraising of $ 500 million and $ 1.8 billion, respectively. The total cumulative investments now exceed $ 4 billion… far from the national budget for public research in the USA, who was from $ 670 million in 2020.

The schedules announced are also very ambitious: Helion announces the production of a few megawatts of electricity from 2024, CFS aims to demonstrate an amplification gain greater than 2 in 2025, General Fusion aims to market a reactor from 2030. Contrasting dates with those hoped for for public initiatives.

If, in the USA, some of these companies benefit from (modest) public funding allowing them to collaborate with national laboratories, all develop and manufacture their own experiments and components. The number of patents filed has therefore increased sharply in recent years, with nearly 160 patents held by 12 companies.

A few arguments can explain the tendency for the proliferation of private initiatives:

• New technologies have appeared or are under development, and could accelerate the development of nuclear fusion and have applications in other areas.

• Iter is in the assembly phase, which reinforces the confidence of investors and decision-makers in the merger.

• Low interest rates are pushing some investors into riskier, but potentially very lucrative, bets. There has also been a sharp increase in investments in the field of climate technologies.

• The climate emergency: many of these companies highlight a possible role for the merger in the energetic transition if it arrives early enough. Promises to be put into perspective in view of the times of technology deployment.

These private initiatives help create a sector and train people in nuclear fusion. They also have the merit of shaking up traditional research by taking more daring technological bets. And if the announced schedules are certainly too optimistic, they will nevertheless make it possible to quickly measure the progress made and to judge whether, finally, nuclear fusion is within reach …