An artist’s rendering of laser beams entering through openings on either end of a hohlraum containing a target pellet. The beams induce nuclear fusion in the pellet by compressing and heating the target. (Lawrence Livermore National Laboratory)

The future of fusion: When might we ‘bottle’ the sun?

Fusion, often referred to as “putting the sun in a bottle,” could help meet our energy needs using nothing more than the hydrogen atoms found in seawater.

By John Heilprin

February 21, 2025

The 2024 GESDA Science Breakthrough Radar® offers some promising insights into the future prospects of nuclear fusion. First and foremost, it suggests that through advances in research and investment, there is growing optimism about the ability to achieve controlled nuclear fusion over the next few decades. Notably, compact nuclear fusion reactors may begin delivering commercial power as early as the 2030s, reflecting significant strides in this technology.

French scientists announced on February 18 that their research into nuclear fusion reached a “crucial milestone” by maintaining a plasma reaction for a record 1,337 seconds, or more than 22 minutes, a week earlier. That broke the previous record set just one month earlier, said France’s Atomic Energy Commission, or CEA, which runs the WEST Tokamak machine in southern France. Using the machine, one of the EUROfusion consortium facilities, the team now aims to achieve longer plasma durations of “up to several hours combined – but also to heat the plasma to even higher temperatures with a view to approaching the conditions expected in fusion plasmas.”

In late January, China’s Hefei Institutes of Physical Science claimed a new world record for maintaining a steady-state high-confinement plasma operation. Working in their Experimental Advanced Superconducting Tokamak (EAST), scientists reported maintaining the operation for 1,066 seconds, almost 18 minutes longer than its previous record of 403 in 2023. The significance of the test was that it showed researchers are more capable of simulating the operational environment of a future fusion power plant.

There has been a noteworthy financial commitment in the field, with over US$6 billion invested in private fusion companies recently, signaling robust commercial interest in developing this clean energy source. The International Thermonuclear Experimental Reactor (ITER), a collaboration among 33 countries based in southern France, is tasked with demonstrating the feasibility of fusion power at a scale necessary for future commercial applications. It plans to produce 500 megawatts of fusion power within the next couple of decades, a critical step towards building supply chains needed for commercial fusion plants.

The energy that powers the sun and the stars is virtually inexhaustible and can be created using hydrogen isotopes. These chemical cousins of hydrogen, like deuterium, can be extracted from seawater.

However, the path to commercial fusion power isn’t without challenges. Materials science still needs significant advancements to ensure the safety and longevity of containment structures in fusion systems. Additionally, discussions are ongoing about the optimal design for fusion reactors, indicating that progress is being made but there is still much to navigate in engineering solutions.

Artificial intelligence could help researchers connect datasets and navigate aspects of the fusion process, such as with the development of materials for fusion reactors that can hold up in extreme temperatures and environments but keep their structural functions and integrity.

Overall, the latest Radar communicates a sense of hope and transformation in the nuclear fusion domain, framing it as a potential solution to global energy needs. With continued investment, innovation, and international collaboration, nuclear fusion could start to emerge as a crucial player in the global shift towards sustainable, zero-carbon energy sources in the foreseeable future.

Over the next five years, the Radar predicts, solar energy will become a larger global source of electricity than coal. Algorithmic innovations will improve the control of supply and demand in electricity markets, freeing more renewable energy to create green hydrogen. And small-scale laboratory fusion successes in privately funded companies will stimulate further investment in research.

Within a decade, half of global electricity will come from renewable sources. Seasonal and long-term energy storage, such as power-to-gas, flow batteries and liquefied hydrogen and air, will become a commercially viable output of wind and solar energy sources. But a quarter-century from now, the Radar predicts, small-scale pilot nuclear-fusion plants will begin to come online. Electrical grid interconnectors will span all of Eurasia, while significant improvements in the energy efficiency of synthetic-fuel manufacture will enable its use for zero-carbon aviation and shipping.

Nuclear power plants rely on nuclear fission, in which atoms are split apart, releasing energy. Most plants use uranium atoms. With fission, a neutron collides with a uranium atom and splits it, releasing a large amount of energy in the form of heat and radiation. More neutrons are released when a uranium atom splits. The neutrons collide with other uranium atoms, a repeating process called a nuclear chain reaction.

In nuclear fusion, two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy. Fusion reactions, which power the sun and stars, take place in a hot, charged gas called plasma, made of positive ions and free-moving electrons. Since the 1930s, when the theory was first understood, scientists and engineers have sought to repeat the process on an industrial scale.

The International Atomic Energy Agency says fusion could generate four times more energy per kilogram of fuel than the fission used in nuclear power plants, and almost four million times more energy than burning oil or coal. Fusion, like fission, does not emit heat-trapping carbon dioxide or other greenhouse gases.

Dozens of countries are conducting fusion and plasma physics research using designs and magnet-based machines like stellarators and tokamaks, along with advanced fuels, lasers, and linear devices. In 2022, an experiment at U.S. Lawrence Livermore National Laboratory showed ignition – a fusion reaction generating more energy than was put in. It demonstrated that fusion could be a viable clean energy source.

“Taking this to the next level requires that we do this over sustained periods and at scale,” says a contribution to the Radar from authors Ian Chapman, Mike Porton, Susana Reyes and Ahmed Diallo. “If this can be achieved, nuclear fusion will provide zero-carbon, sustainable, essentially limitless baseload energy. This is nothing new: we have known it to be possible for around a century. What is new is that, though the field still faces a number of significant challenges, research achievements over the last five years have created genuine optimism that these challenges can soon be overcome.”

Illustrations by the International Atomic Energy Agency (IAEA)

The importance of interdisciplinary collaboration in fusion research

The Radar’s focus on anticipating the future of research connects to advancements in fusion technology in several significant ways.

The Radar identifies fusion technology as one of the emerging scientific fields that can have transformative impacts on society and the environment. The advancements in fusion research could lead to sustainable, clean energy sources, addressing pressing challenges such as climate change and energy equity. Ongoing projects like ITER aim to demonstrate the feasibility of fusion power, which, if successful, could democratize energy production and contribute to decarbonization efforts on a global scale.

The challenges faced in fusion technology, such as those that are related to materials science and superconductivity, require advances across various scientific disciplines. This reflects the broader trend noted by the Radar in which future scientific breakthroughs will necessitate greater cooperation between experts in a range of different fields, including engineering, physics, and social sciences.

Where the science and diplomacy can take us

The 2024 GESDA Science Breakthrough Radar®, distilling the insights of 2,100 scientists from 87 countries, says that when commercial fusion is up and running, the electricity produced will likely be used as a baseload to ensure the stability of electricity production. But it could also help with surge provision, putting it into competition with some very different types of energy production and storage. Fusion can also support hydrogen production through electrolysis, as well as thermal-energy applications.

The findings in the 2024 Science Breakthrough Radar®

Based on the Radar, here’s where we stand in several important areas:

3.1.1 Renewable energy – Radar, page 156

As of 2022, renewable energy sources like solar and wind accounted for approximately 14% of global energy. This is a significant increase from just 1.7% in 2010, driven by decreasing costs and improved efficiency. Solar and wind energy are now often cheaper than fossil fuels, which is likely to make them the preferred energy sources as technology continues to improve. The report highlights optimistic projections for nuclear fusion, which could provide a sustainable and nearly limitless source of zero-carbon energy.

5-year horizon: Solar overtakes coal in electricity production
10-year horizon: Energy-storage innovations grow renewable market share
25-year horizon: Fusion investments begin to pay off

Invited Contribution: The Future of Fusion – Radar, page 296

Fusion has the potential to solve the challenge of energy equity and is a flagship demonstration of science diplomacy. When power-plant-scale fusion is achieved, it will not only be a major advancement that democratizes energy production or a step towards decarbonization, but also a sign of hope for humanity.

Invited Contribution: Anticipating the Future of Research – Radar, page 308

The integration of technologies like AI and advanced data analysis into fusion research can enhance productivity and discovery speed, which are critical given the urgency of global energy challenges.