Nuclear fusion is a type of nuclear energy that offers the prospect of a clean, safe, and virtually inexhaustible energy source for us and future generations. Despite being held back thus far by unresolved engineering challenges, the nuclear fusion industry has had technological breakthroughs in recent years. So, we had to ask: What is the history of nuclear fusion?

Nuclear fusion began in 1934 when it was first demonstrated in a laboratory setting. Then, the invention of the stellarator and tokamak fusion reactors in the 1950s spurred research into fusion’s commercial viability. It is still being researched and does not yet supply energy to our power grid.

One way to combat the current global climate crisis threatening Earth’s environmental, economic, and social health is to transition away from traditional fossil fuels and toward cleaner energy sources, such as nuclear energy. Keep reading to learn how nuclear fusion came to be, who and what pioneered its development, how effective it has been thus far, and what the future of nuclear fusion could entail.

Here’s the History of Nuclear Fusion in a Nutshell

Nuclear fusion, one of two ways to produce nuclear energy, is the generation of energy produced when lighter atoms are combined or fused to create larger and heavier atoms.

“Nuclear fusion: the process of joining two nuclei to produce energy.”

Cambridge Dictionary

Nuclear fusion is still very much in the research and development phase. The fusion process is very hard to control within a laboratory setting. More research and development still needs to be done to determine if fusion could be another viable energy source. 

Nuclear fusion has gone through three distinct development phases in its development:

• Early market formation and innovation: The early history of nuclear fusion dates back to the early 1900s, with studies about the nuclear fusion reaction in stars.

• Consolidation and strengthening: The first laboratory experiment demonstrating nuclear fusion in 1934 kickstarted the nuclear fusion movement, which exploded in the 1950s following the construction of the world’s first nuclear fusion reactor in 1958. 

• Mainstreaming: Nuclear fusion has yet to establish itself as a part of the mainstream energy industry, with the focus still remaining heavily on research and development. The establishment of the International Atomic Energy Agency (IAEA), the International Energy Agency (IEA), the World Nuclear Association (WNA), the International Thermonuclear Experimental Reactor (ITER) Agreement, and the Fusion Industry Association (FIA) have helped to advance the nuclear fusion market.

Understanding nuclear fusion’s history can provide insight into how it can evolve into a commercially viable energy source.

When and How Did Nuclear Fusion Get Started

Radioactivity has always been present on Earth, but it wasn’t seriously studied until the late 1800s. And it wasn’t until 1920 that the concept of nuclear fusion was even realized. 

1920: British astrophysicist Arthur Eddington theorized that stars get their energy from the fusion of hydrogen into helium. His theory laid the foundation of modern theoretical astrophysics.

1929: British and Dutch physicists Robert d’Escourt Atkinson and Fritz Houtermans suggested that fusing nuclei together could produce large amounts of energy. They also calculated the rate of nuclear fusion in stars.

How Has Nuclear Fusion Developed Over Time

Nuclear fusion development exploded in the 1950s following the invention of the first nuclear fusion reactors. Pending more research and development, nuclear fusion could play an important role in the long-term global energy transformation.

What Are Milestones in Nuclear Fusion Development 

The first laboratory experiment demonstrating nuclear fusion kickstarted the nuclear fusion movement, which saw rapid growth beginning in the 1950s. 

1934: Ernest Rutherford fused deuterium into helium and observed an “enormous effect”, a release of energy. This would pave the way for modern nuclear fusion research. 

1934: Australian physicist Mark Oliphant became the first to demonstrate nuclear fusion in a laboratory setting. He also discovered helium-3 and tritium, both of which are used in nuclear fusion, and the fusion reaction which formed the basis for a hydrogen bomb.

1939: German and Indian physicists Hans Bethe and Subrahmanyan Chandrasekhar demonstrated that stars are fueled by nuclear fusion. They identified the “proton-proton chain”, which is the process that enables stars to generate energy and the model for modern fusion.

1950s: Soviet scientists Andrei Sakharov and Igor Tamm conceptualized the tokamak, which, like the stellarator, used magnetic fields to control plasma particles and maintain the right conditions for fusion reactions to occur. Tokamaks are the preferred option today for nuclear fusion energy power plants because they are easier to build than stellarators and are better at keeping plasmas hot.

1951: Lyman Spitzer invented the stellarator, a machine that uses magnetic fields to control plasma particles and maintain the right conditions for fusion reactions to occur. This was the first model for harnessing fusion reactions. 

1958: Nuclear fusion research was declassified at the Atoms for Peace conference in Geneva, which opened the door to researching fusion for energy purposes. Previously, nuclear fusion research was linked only to atomic weapons development. 

1958: The world’s first tokamak fusion reactor, the T-1, was constructed in Russia. 

1983: The Joint European Torus (JET), the largest operational nuclear fusion reactor to achieve nuclear fusion at the time, was constructed.

1991: JET achieved the world’s first controlled release of fusion power. Previously, fusion reactions had only taken place uncontrollably via hydrogen bombs.

2006: The International Thermonuclear Experimental Reactor (ITER) agreement was signed, and the ITER project was formed. ITER is both an international cooperation between 35 countries and the name of what will be the world’s largest and most advanced tokamak reactor.

2021: The world record fusion power was achieved in The Joint European Torus (JET) tokamak. JET produced 59 megajoules of energy, double the previous record amount. It was also the first reactor to run off of a 50-50 mix of tritium and deuterium.

2022: The National Ignition Facility at Lawrence Livermore National Laboratory in California (US) demonstrated the viability of nuclear fusion energy for the first time ever when a fusion reaction produced more energy than was needed to spark the reaction. The machine’s laser fired 2 megajoules onto a target and produced 3 megajoules of energy.

How Has the Nuclear Fusion Market Developed Recently

Nuclear fusion currently does not currently supply energy to the power grid. The focus remains on refining the technology and increasing investments.

What Is the Present Status of Nuclear Fusion

In terms of installed capacity, there are currently more than 10 stellarators and 50 tokamaks in operation worldwide, but there are currently no operating reactors that provide energy to our power grid. 

The world’s largest tokamak, also named ITER, is currently being built in France. Weighing 23,000 tons, the machine will be able to maintain a temperature 10x that of the sun’s core and will have a 500 MW fusion energy output power once constructed. Although it will not be used to generate electricity, the technology of ITER will set the standard for future reactors.

In terms of funding, nuclear fusion investments grew 27% to over $6 billion in 2022. But this is still much less than will be required in the future, given that the cost of ITER is over $20 billion alone. Nuclear fusion is a capital-intensive process; therefore, investments will need to increase before the technology can become commercially viable. 

Presently, the two main challenges to nuclear fusion are maintaining the reaction and generating more energy from the reaction than was required to start the reaction.

Nuclear fusion experiments themselves are relatively easy to achieve; however, the reaction typically only lasts a fraction of a second. The main challenge with nuclear fusion comes with sustaining fusion reactions for prolonged periods of time. To keep a nuclear fusion reaction going, hydrogen isotopes must be confined and maintained at extremely high pressures and temperatures that are several times hotter than the sun.

In 2021, JET held a nuclear fusion reaction for 5 seconds to produce 59 megajoules (MJ) of energy, almost double that of the previous record. However, scientists had to put 3x as much energy into the system as was created by the reaction.

In December 2022, The National Ignition Facility at Lawrence Livermore National Laboratory in California (US) created a fusion reaction that produced more energy than was needed to spark the reaction. The machine’s laser fired 2 megajoules onto a target and produced 3 megajoules of energy. This demonstrated the viability of nuclear fusion energy for the first time ever. 

How Will the Future of Nuclear Fusion Look Like

Nuclear fusion offers the prospect of an inexhaustible energy source for future generations, but it has been held back thus far by unresolved engineering challenges. Achieving fusion energy commercialization will require increased funding and research.

How Nuclear Fusion Will Likely Develop in the Future

Most experts agree that we are unlikely to achieve large-scale nuclear fusion energy generation before 2050. This means that fusion is not an option for meeting the short-term climate goals laid out in The Paris Climate Agreement, which aims to limit global warming to below 2 degrees Celsius (C).

But that doesn’t mean we should give up on nuclear fusion. Nuclear fusion can become a commercially viable energy source if we develop a steady and reliable way of maintaining the fusion reaction. 

In order to achieve commercial energy generation, we must overcome the two main challenges to nuclear fusion: maintaining the reaction and generating more energy from the reaction than was required to start the reaction. This will require increased funding and further technological advancements.

What Policies Are Put in Place to Support Nuclear Fusion Usage

The most well-known piece of legally binding, international climate mitigation legislation is The Paris Agreement, the goal of which is to limit global warming to below 2 degrees Celsius (C), preferably to 1.5C, compared to pre-industrial levels. 

The Paris Agreement specifically notes a transition towards clean energies, such as nuclear energy, as being a critical part of meeting these goals.

Check out the highlights of the 2015 COP21 directly from the UN Climate Change channel:

In addition, The International Energy Agency’s (IEA) Net Zero Emissions by 2050 Scenario is one framework for the global energy sector to achieve net zero CO₂ emissions by 2050 and universal energy access by 2030.

There are many global and country-specific nuclear policies and organizations aimed at meeting the 2050 net zero scenario, including: 

• 1957 – International Atomic Energy Agency (IAEA): The IAEA was founded as fears about nuclear technology began to develop. It is an organization within the United Nations that seeks to promote the safe, secure, and peaceful use of nuclear technologies through international cooperation.

• 1974 – The International Energy Agency (IEA): The IEA was founded in response to the major oil disruptions in 1974. It promotes international energy cooperation, including nuclear energy, and is made up of 31 member countries. 

• 1994 – Nuclear Energy Institute (NEI): The NEI was founded as the policy organization of the nuclear energy industry. They seek to promote the global growth of nuclear energy through effective policies. 

• 1998 – World Nuclear Transport Institute (WNTI): The WNTI was founded to represent the collective interests of the nuclear transport industry. They aim to ensure safety and security in the global transport of nuclear materials. 

• 2001 – World Nuclear Association (WNA): The WNA was established as the leading international organization to represent the global nuclear industry. 

• 2006 – The ITER Agreement: ITER is a global scientific partnership established as a collaborative international project to develop fusion energy for peaceful purposes. Upon construction, the ITER tokamak will be the largest magnetic confinement fusion experiment in the world. 

• 2018 – The Fusion Industry Association (FIA): The FIA was formed to be the voice of the private fusion industry. They are a nonprofit organization comprised of private companies striving to make nuclear fusion commercially viable.

If you are interested in learning more about country-specific nuclear energy (both fission and fusion) policies, you can visit the IEA’s nuclear power policy database.

What Are Currently the Different Types of Nuclear Energy

In general, nuclear energy is generated when neutrons either fuse or divide, which releases heat, produces steam, spins a turbine, and drives generators to produce electricity. The two ways we can generate nuclear energy are via nuclear fission or nuclear fusion.

Nuclear Fission Is How We Currently Produce Nuclear Energy

Nuclear fission is the process by which neutrons are used to split the nucleus of an atom, which releases an enormous amount of energy in the form of heat and radiation. 

Uranium-235 (U-235) is the isotope of Uranium used in nuclear fission because its atoms are easily split apart in nuclear reactors. Each time the reaction occurs, more neutrons are free to strike more and more nuclei, causing a chain reaction that turns a turbine and spins a generator to produce electricity. 

Nuclear fission is expected to continue to play a key role in the clean energy movement. This is because nuclear energy:

• Has a low carbon footprint: On a life-cycle basis, nuclear energy (nuclear fission) emits 12 grams of CO₂ equivalent per kilowatt-hour (kWh) of electricity produced, which is tied for the third-lowest out of all energy types.

• Has a minimal land use impact: Nuclear power produces more electricity on less land than any other clean-air source. A standard, 1,000-megawatt facility requires only a little more than 1 square mile to operate, a number that is 360 and 75 times less than what is required for wind farms and solar power plants, respectively. 

• Generates very little waste: A typical 1,000-megawatt facility produces only three cubic meters of nuclear waste. In comparison, the average coal-fired power plant produces roughly 300,000 tons of coal ash and more than 6 million tons of CO₂ every year.

• Promotes energy security: Nuclear energy contributes to energy security by increasing the stability of our power grids. Unlike renewable energy, which faces variations in supply and demand, nuclear energy can provide a reliable and consistent source of clean energy. 

Nuclear Fusion Is Still in the Research and Development Phase

Nuclear fusion is the process by which lighter atoms are combined or fused to create larger and heavier atoms. The sun and stars get their energy from nuclear fusion, as hydrogen atoms fuse together to form helium and matter converts into energy. 

Fusion reactions take place inside fusion reactors in plasma, a hot, charged gas made of positive ions and free-moving electrons. Deuterium and tritium, isotopes of hydrogen with extra neutrons, are the most commonly used nuclear fusion materials. 

The two most common fusion reactors in use today are tokamaks and stellarators. Both use magnetic fields to confine plasma in the shape of a donut.

• Tokamaks: Induce electric currents inside of the plasma. Tokamaks are easier to build than stellarators and are better at keeping plasmas hot. They are the preferred option today for nuclear fusion energy power plants.

• Stellarators: Use external coils to generate a twisting magnetic field. They require less injected power, have greater design flexibility, and are better at keeping plasma stable than tokamaks. However, they are also more complex to build.

Nuclear fusion is very hard to control within a laboratory setting; therefore, nuclear fusion is still very much in the research and development phase. More still needs to be done to determine if it could be another viable energy source.

If the technology is developed, nuclear fusion could play a key role in the clean energy movement. This is because nuclear fusion:

• Has a low carbon footprint: Nuclear fusion produces little to no greenhouse gas emissions and toxic byproducts, making it one of our most environmentally-friendly sources of energy. One study on tokamak fusion power plants found that they emit less CO₂ than photovoltaic solar systems and less than double those from nuclear fission reactors. 

• Efficiently produces a lot of energy: In theory, it is possible to produce one terajoule of energy with just a few grams each of Deuterium and Tritium. This would be enough to meet the needs of an adult person living in the developed world for 60 years. Estimates also suggest that nuclear fusion alone could generate up to 4 times more energy per kilogram of fuel than nuclear fission and nearly 4 million times more energy than burning oil or coal. 

• Uses materials that are readily available: The fusion reaction is most readily feasible between deuterium and tritium, two isotopes of hydrogen. Deuterium is naturally abundant in seawater, and tritium can be bred from lithium, which is naturally abundant in the Earth’s crust and in seawater. Compare this to Uranium-235, the ingredient for nuclear fission, which has a concentration of only 2.8 parts per million (0.7% abundance) in the Earth’s crust.

• Does not produce nuclear waste: Unlike nuclear fission, nuclear fusion reactions do not produce long-lived nuclear wastes. The only byproducts are helium (an inert gas) and tritium. Although tritium is radioactive, it is produced and consumed within the plant in a closed circuit and is only used in low amounts. 

• Cannot cause a nuclear accident: Unlike nuclear fission, nuclear fusion reactions are not based on chain reactions. Plasma must be kept at very high temperatures and pressures, with the support of external heating systems and magnetic fields. If there is a loss of pressure or temperature, the reactor shuts down with no adverse effects to the outside world.

• Cannot be used to produce nuclear weapons: Hydrogen bombs do use fusion reactions; however, they require an additional nuclear fission bomb to detonate. Fusion fuel is also continuously injected and consumed in fusion reactors, so there is never enough fuel lying around to produce a weapon.

• Promotes energy security: Nuclear energy contributes to energy security by increasing the stability of our power grids. Unlike renewable energy, which faces variations in supply and demand, nuclear energy can provide a reliable and consistent source of clean energy. 

Final Thoughts

The early history of nuclear fusion dates back to the early 1900s, with studies about the nuclear fusion reaction that naturally occurs in stars. When Mark Oliphant demonstrated nuclear fusion in a laboratory setting, he kickstarted the nuclear fusion movement. The invention of the stellarator and tokamak fusion reactors in the 1950s spurred further research into fusion’s commercial viability.

Currently, nuclear fusion does not supply energy to our power grid. The focus remains on refining the technology and increasing investments. There are currently more than 10 stellarators and 50 tokamaks in operation worldwide, but none produce electricity.

Most experts agree that we are unlikely to achieve large-scale nuclear fusion energy generation before 2050. The future of nuclear fusion will depend on us overcoming the two main challenges to nuclear fusion: maintaining the reaction and generating more energy from the reaction than was required to start the reaction. This will require increased funding and further technological advancements. 

Stay impactful,

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