Nuclear Fusion Breakthrough

On December 2022, researchers from the National Ignition Facility achieved fusion ignition for the first time in history. The energy potential of nuclear fusion is superior to all other sources of energy that we know on Earth. Controlled nuclear fusion releases nearly four million times more energy than the chemical reactions that occur when burning fossil fuels like coal, oil, or gas.

Aaron Baker

Apr 28, 2023 • Updated May 12, 2023 • 5 min read
Find nuclear fusion and other environmental hazards near you here


On December 5, 2022, researchers from the National Ignition Facility at the Lawrence Livermore National Laboratory in California achieved fusion ignition for the first time in history. Significantly, they produced more energy through a controlled nuclear fusion reaction than the lasers used to drive it, manufacturing a net gain of energy for the first time. This nuclear fusion breakthrough has raised hopes that one day, fusion could provide a bountiful, clean energy source devoid of the pollution and greenhouse gases caused by burning fossil fuels and the radioactive waste produced by existing nuclear power plants. According to astrophysicist Neil deGrasse Tyson in an interview with CBS news, "The day you get more energy out than you put in, the sky's the limit." Of all the renewable energy sources, fusion is the only one with the potential to fully power our planet. Though, we are still decades away from realizing its full potential.

History of Nuclear Fusion Research#

Our understanding of nuclear fusion began over 100 years ago when British Astrophysicist Arthur Eddington suggested that stars draw their energy from hydrogen fusion into helium. In 1934, Ernest Rutherford and his student Mark Oliphant achieved nuclear fusion for the first time at Cambridge University. In their experiment, they realized the fusion of deuterium, a heavy isotope of hydrogen, into helium. 

What Is the Difference Between Nuclear Fusion and Nuclear Fission?  #

The main difference is that fission is the splitting of an atom into two smaller ones while fusion is combining two atoms to form a new larger atom.  Commercial nuclear power plants produce electricity by splitting uranium. Unlike fusion, when uranium is split in a nuclear fission reactor, it produces radioactive waste which is dangerous to human health and difficult to store.  See our article on nuclear power plants for additional information about nuclear fission. 

In the 1950s, the design and construction of fusion machines began. Researchers in the US developed and built the Stellarator, and scientists in the former Soviet Union produced the Tokamak. Both devices use magnetic fields to contain plasma long enough for fusion, known as magnetic confinement fusion, to occur. These designs are still used in fusion research today, including at the International Thermonuclear Experimental Reactor (ITER) facility in France–a 34-nation collaborative effort to produce clean energy through nuclear fusion.

In the 1970s, work began on inertial confinement fusion (ICF), which involves compressing and heating the fuel for nuclear fusion using lasers. Initial results in the 1970s and 1980s were lower than expected. The fusion process took more energy than it produced. So,  researchers continued to build larger and more efficient machines. The largest ICF machine is located at the National Ignition Facility in California. Here, 192 lasers focused on a fuel pellet contained in a cylinder (known as a hohlraum) the size of a pencil eraser and achieved fusion ignition for the first time in history when they delivered 2.05 megajoules of energy resulting in 3.15 megajoules of nuclear fusion output. Although this is a relatively small amount of energy (about enough to power a hairdryer for 30 minutes), it was produced almost instantaneously–about the amount of time it takes light to travel one inch. A sustained nuclear fusion reaction using only a few grams of fuel, about the size of a nickel, could produce nearly all of the energy a person in the US uses in their lifetime.

A NIF hohlraum. The hohlraum cylinder, which contains the NIF fusion fuel capsule, is just a few millimeters wide, about the size of a pencil eraser, with beam entrance holes at either end. The fuel capsule is the size of a small pea.

What Is Nuclear Fusion Power and Could It Solve the Energy Crisis?#

The heat and light produced by stars, including our sun, result from nuclear fusion. The extreme pressure produced by the immense gravity in stars strips electrons from some atoms and creates a state of matter called plasma. In this state, hydrogen atoms move so fast that they collide and fuse. When two hydrogen atoms combine, the mass of the helium that results is less than the sum of the initial atoms. The lost mass, in the form of a high-energy neutron, is the energy released.  

The most efficient fuel for a fusion reaction discovered by researchers is deuterium and tritium–two isotopes of hydrogen. When the two isotopes are heated and compressed, they undergo fusion, form helium, and release energy. Scientists’ ultimate goal is to use  self-sustaining nuclear fusion reactions in a power plant to generate electricity. The high-energy neutrons released in the reaction would be captured, and their kinetic energy would be transformed into heat. This heat can then be used to warm water, create steam and turn turbines to generate power--much like how we use heat energy in a fossil fuel or nuclear fission power plant to generate electricity.

A mixture of deuterium and tritium — two hydrogen isotopes — will be used to fuel future fusion power plants. Inside the reactor, deuterium and tritium nuclei collide and fuse, releasing helium and neutrons. (Image: IAEA/M. Barbarino)

What Is the Potential Benefit of Nuclear Fusion?#

The energy potential of nuclear fusion is superior to all other sources of energy that we know on Earth. Controlled nuclear fusion releases nearly four million times more energy than the chemical reactions that occur when burning fossil fuels like coal, oil, or gas and four times more energy than nuclear fission that we currently use in nuclear power plants. In theory, with just a few grams of fuel, controlled nuclear fusion could produce a terajoule of energy, which is approximately the energy used by one person in a developed country over 60 years.

Energy production through nuclear fusion would essentially be an emissions-free source of power. It would help reduce and eliminate the need for power plants that burn coal and natural gas. Most scientists agree that to address climate change, we need to  limit global warming to 1.5 or 2 degrees Celsius or there could be catastrophic impacts for humans and the planet.  If fully realized, nuclear fusion could be a significant part of the solution for emission-free energy and end our use of fossil fuels.  See our FAQ section below for pros and cons of nuclear fusion.

When Will Nuclear Fusion Power Plants Be Viable?#

There are numerous challenges to wide-scale adoption of fusion reactors. The biggest challenge will be to develop the technology to produce more energy on a much larger scale. The net gain of energy that was achieved in December is a historic scientific breakthrough, but the net energy gain of a factor of about 1.5 (2.05 megajoules of energy was used to produce 3.15 megajoules) will likely need to reach 30-100 in order to run a power plant. Both the efficiency and the scale will need to be increased before electricity production can be practical.

Maintaining a supply of the fuel source for fusion, the two isotopes of hydrogen, could also pose a challenge. Deuterium naturally occurs in water in high enough concentrations that a few gallons would provide as much energy as a supertanker of oil.  Tritium, though, is extremely rare and would need to be produced. Scientists believe that adding lithium, which is widely distributed in the Earth’s crust, to fusion reactors could produce sufficient tritium to overcome this challenge.

Additional challenges involve the infrastructure required to store and transport the energy produced by nuclear fusion. The network of transmission lines capable of transmitting the high voltage electricity produced by fusion will need to be expanded.  Nuclear fusion also produces energy continuously.  As a result, more electricity will need to be stored during times of low demand. This could be accomplished using a variety of advanced energy storage systems including battery, pumped hydroelectric, or a power-to-gas system that produces hydrogen.

Most scientists agree that we are still decades away from electricity supplied by nuclear fusion power plants, although additional technological breakthroughs could speed this timeline up. Nevertheless, the promise of a near infinite supply of carbon-free energy is staggering. With the billions of dollars governments and the private sector are investing in research, there is hope that breakthroughs in the efficiency and scale of nuclear fusion could lead to the development of power plants in our lifetimes.

Frequently Asked Questions

Find information for climate, natural, and environmental hazards in the United States with AreaHub in seconds. With a free AreaHub report, access data about 18 potential dangers in your zipcode, like wildfires, extreme weather, hurricanes, and radon. With AreaHub's Plans, access 27 potential dangers near your home, like heatwaves, solid waste landfills, and facilities in the toxics release inventory and more, and monitor your area for severe weather alerts and pollution incidents.