Gandhinagar: Institute for Plasma Research (IPR) has commissioned India’s first Small-Scale Spherical TOKAMAK (SS-ST), marking a groundbreaking milestone in the nation’s fusion energy research landscape.
The move strengthens India’s experimental capabilities in plasma physics and adds to its existing TOKAMAK infrastructure — now making three operational TOKAMAKs in the country. small-scale spherical tokamak India is rapidly emerging as a key focus in compact fusion science with potential cost and space advantages over conventional machines.
The SS-ST marks a leap in indigenous research design and assembly, enabling scientists to study plasma confinement physics in a unique compact mode. With precise manufacturing and advanced diagnostics, this machine positions IPR at the forefront of next-generation fusion experimentation in India.
What Is a Spherical TOKAMAK?
A spherical TOKAMAK is a type of magnetic confinement device used to hold extremely hot plasma — a key step toward achieving controlled nuclear fusion. Unlike conventional tokamaks, which have a doughnut-like shape with a large central hole, spherical tokamaks are more compact and have a tighter aspect ratio. This design can potentially reduce magnet strength requirements and cost, while still enabling effective plasma confinement.
The compact configuration also presents engineering challenges, including tighter space for magnetic coils and precision requirements during assembly. These challenges are part of what IPR aims to study and overcome with its new SS-ST facility.
India’s Growing TOKAMAK Portfolio
Prior to the small-scale spherical tokamak, IPR already operated two major TOKAMAKs:
- ADITYA-U – India’s first indigenously designed and fabricated tokamak, operational since 1989 (upgraded into a divertor configuration).
- SST-1 (Steady State Tokamak-1) – A larger, superconducting tokamak focused on steady-state operation and advanced plasma physics research.
With Small-Scale Spherical Tokamak joining these two, India now boasts three operational TOKAMAKs — a strong foundation for comprehensive plasma experiments spanning from conventional to advanced configurations.
Details of Small-Scale Spherical Tokamak
The commissioning of SS-ST represents the first spherical tokamak in the country. Its compact design allows researchers to explore new physics regimes that complement conventional tokamak studies, helping diversify India’s fusion research capabilities.
Indigenous Design and Fabrication
All critical components of the SS-ST were designed and developed in India with support from domestic industries, showcasing strength in high-precision engineering and scientific collaboration across research and private sectors.
Successful First Plasma
Early experiments achieved successful plasma initiation (first plasma) on 11 December 2025, illustrating the machine’s readiness for detailed research runs. Diagnostic systems, magnetic power supplies, hydrogen gas feed, and vacuum systems all performed reliably during initial tests.
Platform for Future Research
The SS-ST is expected to serve as a vital testbed for studying plasma behaviour under unique magnetic and geometric conditions. These insights will aid India’s fusion roadmap and may inform the development of future fusion power systems.
About Institute for Plasma Research (IPR)
The Institute for Plasma Research is an autonomous research organization under India’s Department of Atomic Energy, based in Gandhinagar, Gujarat. IPR conducts both theoretical and experimental plasma physics research and contributes to industrial plasma technology applications.
Its work spans multiple tokamaks and fusion-related projects, and it plays a significant role in India’s partnership in the international ITER experiment, aimed at achieving practical fusion energy through global collaboration.
Importance of Small-Scale Spherical Tokamak for India
With the addition of the small-scale spherical TOKAMAK to its research infrastructure:
- India strengthens its position in global fusion science.
- Students and researchers gain access to new experimental platforms.
- Domestic industry involvement showcases engineering capability in precision nuclear-grade manufacturing.
- Future progress toward practical fusion energy receives a strategic boost.
