India has launched a pilot hydrogen production facility that uses heat from a nuclear reactor instead of conventional grid electricity to generate clean hydrogen.The facility, set up by the Department of Atomic Energy at the Indira Gandhi Center for Atomic Research (IGCAR) in Kalpakkam, Tamil Nadu, uses high-temperature heat from the Fast Breeder Test Reactor to split water into hydrogen and oxygen through an indigenously developed process, an important step in nuclear-aided clean energy research.
What is the Copper-Chlorine Thermochemical Cycle?
To understand the significance of the development, it is important to note how hydrogen is typically produced. The most widely used method today is steam methane reforming, which relies on natural gas and high heat to extract hydrogen from fossil fuels, resulting in what is known as gray hydrogen with substantial carbon emissions.A cleaner alternative is electrolysis, which uses electricity to split water into hydrogen and oxygen. When powered by renewable energy sources such as solar or wind, the process produces green hydrogen without any direct carbon emissions.However, scientists have also been developing a third route, the copper–chlorine (Cu–Cl) thermochemical cycle, for decades. Developed indigenously by the Bhabha Atomic Research Center (BARC) in Mumbai, the process does not depend on electricity as the primary input. Instead, it uses high-temperature heat, such as that generated by a nuclear reactor, to drive a series of chemical reactions involving copper and chlorine compounds, which are continuously recycled within the system.Through this closed-loop cycle, water is split into hydrogen and oxygen, while the copper and chlorine compounds are reused. The process does not involve burning fossil fuels and produces no direct carbon dioxide emissions.
A fast, clean way to make hydrogen
Scientists are particularly encouraged by this development, not only because it eliminates carbon emissions, but also because of its potential efficiency benefits. While electrolysis can also produce clean hydrogen when powered by renewable energy, it involves multiple energy conversion steps, each of which has disadvantages.In contrast, the copper–chlorine (Cu–Cl) thermochemical cycle allows heat to be used directly to drive chemical reactions, bypassing the need to convert heat to electricity first. By eliminating this intermediate step, the process has the potential to extract more hydrogen from the same amount of energy input.The cycle operates at around 500°C, which is a relatively moderate temperature compared to other thermochemical methods, which require much higher heat levels and are therefore more challenging to deploy on a large scale. Fast breeder reactors, such as the Fast Breeder Test Reactor (FBTR) at Kalpakkam, are capable of supplying heat in this temperature range, making this approach technically more viable for real-world application.
Kalpakkam reactor key to new hydrogen technology demonstrator
The Fast Breeder Test Reactor (FBTR) at the Indira Gandhi Center for Atomic Research (IGCAR), Kalpakkam, has been a key pillar of India’s nuclear research program for decades. It is a sodium-cooled fast reactor that uses liquid sodium as a coolant instead of water, which enables it to operate at higher temperatures than conventional reactors. This makes it particularly suitable for supplying the process heat required for the copper-chlorine (Cu-Cl) cycle.FBTR has also made significant contributions to the development of fuel, materials and related technologies under India’s three-stage nuclear power programme, including the 500 MW Prototype Fast Breeder Reactor, which is currently under advanced development at Kalpakkam as its major second stage.According to the Department of Atomic Energy, the newly inaugurated hydrogen facility is a technology demonstrator designed to validate the process under actual operating conditions, generate performance data and support further optimization before potential scale-up. The project is the result of a joint effort between BARC and IGCAR, involving years of research, engineering design, construction and testing before commissioning.
What is ‘pink hydrogen’ and why does it matter?
Hydrogen produced at the facility is often called “pink hydrogen”, a term used for hydrogen produced using nuclear power as the primary source, with no direct carbon emissions. It is classified as one of the clean routes for hydrogen production along with green hydrogen produced from renewable energy and blue hydrogen derived from natural gas with carbon capture.What sets pink hydrogen apart, and what the new Cu-Cl facility demonstrates, is the ability of nuclear power to provide a continuous, weather-independent source of clean hydrogen. Unlike solar and wind power, which are intermittent and dependent on weather conditions, nuclear reactors operate around the clock.As a result, a nuclear heat-based hydrogen system can produce hydrogen 24/7 without interruption, providing a stable and reliable supply. This stability is especially important for industries that require large-scale, continuous hydrogen availability.
Hydrogen to power heavy industry
The industries that rely heavily on hydrogen today, including fertilizer production, petroleum refining and steel manufacturing, are also among India’s largest sources of carbon emissions. Fertilizer plants alone use large amounts of hydrogen to produce ammonia, with most of this hydrogen currently obtained from natural gas.If nuclear heat-based hydrogen production can be scaled up at a competitive cost, it could provide these sectors with a viable pathway to decarbonization without requiring major changes to their core industrial processes.Hydrogen is also being explored as a potential fuel for heavy transportation, including trucks, ships, and possibly trains. In these applications, hydrogen offers advantages over batteries due to its higher energy density per kilogram, making it more suitable for long range and heavy load operations where battery weight becomes a limitation.Therefore, a stable, low-carbon supply of hydrogen produced sustainably using nuclear power could play an important role in accelerating India’s broader decarbonization efforts.
From electricity to hydrogen: India’s nuclear vision grows
India’s nuclear power program has long been guided by a long-term vision that extends beyond power generation. Conceived by Dr Homi Bhabha, the three-phase program aims to eventually harness the country’s abundant thorium reserves as fuel.The integration of hydrogen production into this framework further expands the role of nuclear power, taking it beyond power generation to clean fuel production. According to Ajit Kumar Mohanty, Secretary, Department of Atomic Energy (DAE), this development reflects India’s growing capabilities in advanced nuclear technologies and shows that the contribution of nuclear energy to a sustainable future can extend far beyond conventional reactor applications.