Private nuclear fusion companies have seen a cumulative investment of over US$9.6 billion to date in 2025, promising an approach to continuous green energy with high density, no risk of meltdown, and abundant fuel supplies. IDTechEx's report, "Fusion Energy Market 2025-2045: Technologies, Players, Timelines", covers fuel and reactor types along with a quantitative benchmarking scheme and industry timelines for the next 20 years.
Nuclear fusion describes a reaction that takes place in which two or more atomic nuclei are fused to form one or more nuclei and some neutrons. It is the process which powers main sequence stars like the sun, and in terms of mass conversion, it's the most efficient way of generating energy from matter. Nuclear fusion could provide a continuous source of green energy with no risk of meltdown or long-lived nuclear waste that may be associated with fission.
Deuterium and tritium are the most common fuel types used for fusion reaction in the commercial market, releasing +17.6 MeV of energy per reaction. This energy is several orders of magnitude higher than the result of chemical reactions in fossil fuel combustion. IDTechEx's report covers many other types of fuel reactions that can be produced by nuclear fusion processes.
Nuclear fusion vs nuclear fission
Though both nuclear fusion and fission are completely different processes and require vastly different fuels. While nuclear fusion sees smaller nuclei fused into a larger nucleus, nuclear fission splits a larger nucleus into smaller nuclei. Fuels for nuclear fusion are the lightest elements, such as hydrogen or helium isotopes, producing low atomic mass products as a result. In nuclear fission, the standard fuels used are heavy elements such as uranium, plutonium, and thorium, which are split into products with a mid-range atomic mass as well as multiple high energy neutrons.
The regulation surrounding the two processes also differ due to the different radiological hazards that arise as a result. Nuclear fusion can produce short-lived radioactive isotopes due to high energy neutrons, but without long-lived nuclear waste. As a result, there is no need for thousands of years of underground storage as with nuclear fission.
Market drivers for commercial fusion
IDTechEx outlines how the main market drivers for commercial fusion are currently coming together at the most advantageous time in order to create an impact on the market. The science of fusion and recent developments in plasma physics may be beneficial, though the growing global demand for clean energy and reliable and continuous sources is also catching attention. This is particularly true for data centers, and one reason for big tech companies such as Google and Microsoft to be displaying an interest in fusion. Lastly, the recent maturation of enabling technologies such as materials and components suppliers will allow for nuclear fusion to take off within commercial sectors.
It can be argued that one of the biggest challenges within the commercial fusion energy market is not the competition of other fusion startups, but the displacement of other conventional power sources. However, all current energy sources have issues with providing continuous green energy. This is largely surrounding their inevitable intermittency as a result of energy sources relying on nature, such as with wind or solar energy, and their subsequent unresponsiveness to demand without the deployment of energy storage.
IDTechEx highlights fusion energy as being a solution to this intermittency problem, with a continuous power output available and therefore an unmatched reliability. Fusion power plants will have a low footprint compared to the power output they can produce, capable of providing 200-2000MW of power per plant.
The commercial landscape for fusion energy
The fundamental challenge in achieving commercial fusion is in confining the fusion plasma, with fusion reactors today being categorized by their confinement mechanism. IDTechEx outlines multiple approaches that have potential for market impact over the next 20 years, including tokamak, stellarator, field-reversed configuration, spherical tokamak, laser driven inertial confinement, magnetized target fusion, pulsed magnetic fusion, and Z-pinch.
Deuterium-tritium is the most popular fusion fuel used, with the lowest energy barrier. However, it relies on difficult-to-source tritium fuel. The majority of energy released is in high energy neutrons which are unsuitable for direct energy conversion, and neutron activation can cause radioactivity. Many alternatives are also being explored, including aneutronic reactions. There is ongoing research and developments to reduce radioactive risks from fusion processes, which IDTechEx describe as a side effect rather than an unavoidable feature.
For more information, visit IDTechEx's report, "Fusion Energy Market 2025-2045: Technologies, Players, Timelines", and the wider portfolio of Energy & Decarbonization Research Reports and Subscriptions.