The field of nuclear fusion has witnessed a series of advances over the past few months. Developments on this front have been occurring in leading technology hubs around the world, from the United States of America (USA) to China, Russia, India, South Korea and Europe. This has triggered a newfound fascination with nuclear fusion research.

On 5 December 2022, scientists at the National Ignition Facility (NIF) at the Lawrence Livermore Laboratory, California generated more energy from a fusion reaction than the input. The event was a major first in the field and represented a breakthrough in the decades-long effort to replicate the power of the sun on earth. Researchers estimate that continued progress backed by funding will enable the production of 100% pure, inexhaustible energy within the next forty years. The realization of a sustained yet safe nuclear fusion process makes possible the achievement of a potentially limitless source of energy. It therefore presents a solution to tackle the global climate and energy crisis.

Energy Unlimited: How Nuclear Fusion Works

In comparison to nuclear fission which divides the atom, nuclear fusion is the process where atomic nuclei fuse together to form a new atom. Fusion is the fundamental reaction that powers the sun and other stars in the universe. The fusing together of hydrogen atoms effectively enables stars, including the sun, to yield energy in the form of heat and light. However, fusion occurs at the sun’s core at extremely high temperatures of about 100 million degrees Celsius under extreme gravitational pressure.

A fusion reactor attempts to replicate such conditions of extreme heat and pressure in a confined environment by creating a plasma, the superheated, charged state of matter composed of electrons and atomic nuclei. A fusion reaction occurs when the temperature of the plasma is maintained above the reactor’s critical ignition temperature. However, maintaining plasma at the required temperatures has been seen to be extremely challenging in practice.

Nuclear-fusion based energy generation has several advantages in comparison to nuclear fission, the process used in currently deployed nuclear power plants. Fusion processes entail reduced levels of radioactivity and are said to be safer. Most importantly, fusion does not generate harmful radioactive waste and hence poses less of a threat to the environment.

Recent Breakthroughs

The researchers at NIF achieved fusion ignition for the first time by recreating conditions resembling the sun. Simply put, fusion ignition represents the point where the energy generated either equals or exceeds the energy it was fed. The experiment employed 192 laser beams to fire at a gold canister housing a 0.04-inch (1mm) fuel pellet composed of deuterium and tritium – two isotopes of hydrogen. The fuel pellet was compressed to around twenty times the density of lead and heated up to 3 million degrees Celsius. The gold canister was maintained at a temperature of approximately 100 times hotter than the surface of the sun. During the experiment, the fuel and canister evaporate in a billionth of a second. The reaction only lasted for a few seconds and damaged some diagnostic apparatus. However, scientists believe they were able to gauge an accurate reading of the energy generated during the fusion reaction.

Meanwhile, China has also been gaining headway in nuclear fusion R&D, although it is not known to have achieved fusion ignition yet. China's Experimental Advanced Superconducting Tokamak (EAST), also known as the “artificial sun” achieved a significant milestone on 12 April 2023. The EAST was established in 2006 at the Institute of Plasma Physics of the Chinese Academy of Sciences (ASIPP) in Hefei, Anhui Province. The tokamak sustained high plasma temperatures for about six-and-a-half minutes. This achievement broke the previous record set in 2017 where high temperatures were sustained for 101 seconds. The reactor had previously managed to successfully preserve plasma for about eighteen minutes at a temperature of about 70 million degrees Celsius in 2018. The reactor has supposedly undergone more than 120,000 tests. Beijing is on track to make another significant advancement in the field after the recent successes. It has reportedly finished designing the Engineering Test Reactor (CFETR), the next-generation artificial sun which is expected to start operating in 2035.

Challenges Remain

Scientists have been progressively upgrading various components and processes associated with nuclear fusion energy generation for many decades. Continuous R&D can make the procedure more effective. However, technical challenges remain. To begin with, lasers were not developed until 1960. The NIF, which can deliver one million joules of energy to a target was regarded as most powerful laser facility in the world when the U.S. government finished building it in 2009. It produces two million joules per second, which is 50 times more energy than the next strongest laser on earth. The efficiency of this process can only be increased through employing stronger yet less energy-intensive lasers, which may be achievable.

Further, fusion conditions are extremely difficult to maintain. A minor flaw in the fuel or capsule can increase the amount of energy needed and reduce efficiency. Efforts have been made to increase the efficiency of the energy transfer from the laser to the canister and the X-ray radiation transfer from the canister to the fuel capsule. Still, existing technologies can only deliver 10-30 percent of the total laser energy to the canister and the fuel. Challenges also remain with fuel availability. Whereas deuterium, one component of the fuel, is naturally abundant in sea water, tritium is much less common. Tritium is created during fusion; efforts to find a direct technique to extract Tritium or find alternative fuels are still a work in progress.

Researchers at Lawrence Livermore did achieve fusion ignition for a few seconds. However, the size of the achievement is far below what would be needed to produce electricity for daily use, much less usher in a new era of clean energy. The estimated power requirements did not account for the power required to construct and outfit the equipment. Ironically, the experimental setup's diagnostic instruments were harmed by the higher-than-expected energy yield, raising questions about whether ignition was achieved.

Miles to Go

In a few decades nuclear fusion could reach a point where it can be considered a green and sustainable energy force. According to Lev Artsimovich, who is fondly known as the father of the tokamak, fusion will be present when civilization really needs it. While nuclear fusion offers a solution to solve the world’s climate and energy crises, R&D has a long way to go.

Substantial thought needs to be given to any proposition that presents nuclear fusion as the ultimate form of next generation energy. Most of the commercial fusion energy projects rely on various forms of magnetic confinement which presents significant engineering issues. Affordability is also a factor. For instance, the NIF is a facility set up to conduct nuclear weapon research which receives billions of dollars of funding from the US government. Taking the technology from cutting-edge research facilities to integrate the same into a power grid may not be feasible in the current scenario.

Challenges are even more for a country like India where nuclear power generation faces obstacles on several fronts ranging from economic to political to infrastructural. However, recent developments in nuclear fusion research and technology ought to increase public interest and financial investment in the area. Moreover, India can look to get ahead through international collaborations such as International Thermonuclear Experimental Reactor (ITER) and joining hands with its strategic partners.

Disclaimer: The article expresses the author’s views on the matter and do not reflect the opinions and beliefs of any institution they belong to or of Trivium Think Tank and the StraTechos website.