India’s quest to build an “artificial sun” has just moved significantly closer to reality. The Institute for Plasma Research (IPR) in Gujarat has announced the successful installation and commissioning of a new 82.6 GHz, 400 kW gyrotron system on the indigenously built SST-1 tokamak. This upgrade is being hailed as a critical milestone in India’s nuclear fusion program, as it directly addresses one of the biggest challenges in harnessing fusion energy — heating and confining ultra-hot plasma for extended periods.
SST-1 (Steady State Tokamak-1) is India’s own experimental fusion device, designed to replicate the nuclear fusion process that powers stars like our Sun. Unlike conventional power generation that burns fuel, fusion attempts to combine light atomic nuclei under extreme temperature and pressure to release enormous amounts of energy. India has already achieved plasma temperatures exceeding 200 million degrees Celsius — roughly 20 times hotter than the core of the Sun. However, reaching extreme temperatures is only half the battle. The real challenge lies in keeping that superheated plasma stable and confined long enough for fusion to become a viable energy source. This is exactly where the new gyrotron plays a crucial role.
A gyrotron is a powerful device that generates high-frequency microwave energy. The new system injects energy into the plasma inside SST-1 at a frequency of 82.6 GHz and a power of 400 kW, helping scientists heat and sustain the plasma at extreme temperatures. Compared to the earlier 42 GHz system, this new device represents a significant upgrade in heating capability. According to IPR, the new 82.6 GHz system can deliver up to 400 kW of radio frequency power with a pulse duration of 0.5 seconds for Electron Cyclotron Resonance Heating (ECRH) experiments. SST-1 will use this system for second harmonic heating at a toroidal magnetic field of 1.5 Tesla, and for fundamental harmonic heating at 3 Tesla. It works alongside the existing 42 GHz, 500 kW system, giving researchers far greater experimental flexibility.
Unlike the Sun, which relies on its immense gravitational pull to confine plasma, tokamaks on Earth must use powerful magnetic fields to suspend plasma within a ring-shaped chamber, preventing it from touching the walls. Even the slightest instability can disrupt the delicate conditions needed for fusion. The new gyrotron will strengthen researchers’ ability to understand plasma behavior, particularly their capacity to sustain hotter plasma under more stable conditions. IPR describes ECRH as an essential system for plasma start-up, heating, current drive, and instability control — and this upgrade directly serves India’s broader research program in magnetically confined hot plasmas and fusion technology.
Nuclear fusion is often described as the ultimate clean energy dream. Its fuel is abundant, primarily extracted from seawater, and it produces far less long-lived radioactive waste compared to traditional nuclear fission. However, transforming fusion from an experiment into a reliable source of commercial electricity remains one of the most daunting challenges in science and engineering. The new gyrotron will not instantly turn SST-1 into a fusion power plant, and India’s “artificial sun” does not yet generate electricity. SST-1 is an experimental fusion research device, not a commercial power reactor. The new gyrotron is a tool for heating and studying plasma — it does not mean India is already producing power through fusion. But it significantly enhances India’s ability to study sustained ultra-hot plasmas, a crucial step from setting temperature records toward learning to control them.
Notably, India’s fusion research is now advancing on two fronts simultaneously. Bengaluru-based startup Pranos Fusion has unveiled “Pragya,” India’s first privately developed compact tokamak. Pragya is a low-aspect-ratio compact tokamak that will serve as an experimental platform for researching and controlling plasma. The device was built in about eight months and is planned to operate for nearly two decades, aiming to conduct 10 to 12 experiments per day — roughly 3,000 plasma discharges annually — generating vast amounts of data on plasma behavior, tokamak design, and control systems. Pranos plans to use the facility to test plasma control techniques, high-temperature superconducting magnets, diagnostic equipment, and other critical systems. The company’s long-term roadmap includes bringing its high-temperature superconducting magnet technology online by 2027 and building a net-gain fusion reactor called PraniQ by 2030.
For India, the latest milestone brings the country’s “artificial sun” closer to its next breakthrough. The entry of the private sector adds a new dimension to India’s traditionally government-led fusion research, while the commissioning of the new gyrotron on SST-1 strengthens the foundational research capacity of national laboratories. Together, they are pushing India into a stronger position in the global race to harness the power of the stars to light up the Earth.
