PFBR, built by Bharatiya Nabhikiya Vidyut Nigam Limited (BHAVINI), is currently in the final stage of commissioning. PFBR marks the commencement of the second of the three-stage commercial nuclear power production, planned by Homi Jahagir Bhabha way back in 1950.

This is an occasion for the entire Department of Atomic Energy (DAE) fraternity -- and for that matter for every Indian -- to be proud of the combined achievement of the BHAVINI and Indira Gandhi Centre for Atomic Research (IGCAR) teams.

In October 2004, then Prime Minister Manmohan Singh had marked the occasion by starting concreting of PFBR Raft.

This highly complex reactor is now nearing completion.

Visits of Prime Ministers, President (Abdul Kalam), several Union Ministers, Director Generals of International Atomic Energy Agency (IAEA) (Mohamed ElBaradei and Yukiya Amano), Deputy Director Generals of IAEA, several other international dignitaries and ambassadors, Parliamentary committees, many Padma Awardee Scientists and others to PFBR in the past, is a testimony the importance of PFBR in the global scenario.

The fast breeder reactor technology has the potential to generate more nuclear fuel (plutonium) than it consumes. This is achieved by using fast neutrons to convert fertile material (depleted uranium) into fissile material. The PFBR contributes to India's efforts to achieve energy security by efficiently utilising its indigenous uranium and abundant resources of thorium.

PFBR is a stepping stone to move from U235 fuel to U233 fuel. PFBR is designed and constructed entirely in India, showcasing the country's capability in advanced nuclear sciences and engineering, and close fuel cycle.

The PFBR is a significant achievement in India's indigenous nuclear reactor technology capabilities.

For concerted efforts to make fast reactors commercially viable, eminent scientist Anil Kakodkar initiated to launch the fast breeder reactors through a new company, BHAVINI. Late Baldeo Raj, then Director of IGCAR, and his team played a leading role in plant and equipment design, testing and qualification of equipment. IGCAR, in close proximity to PFBR construction site, has provided multi disciplinary support to PFBR and trained PFBR operation personnel in Fast Breeder Test Reactor (FBTR).

The PFBR project has brought several laurels for India, contributing to the country's nuclear energy programme and technological prowess. Achievements and accolades associated with the PFBR encompass Indigenous technology development and demonstrate the country's capability to design, construct, and operate advanced nuclear reactors without relying on foreign assistance.

PFBR involves cutting-edge research and innovation in nuclear reactor technology. It fosters advancements in reactor design, materials science, safety analysis, and operational efficiency.

The PFBR project has facilitated collaboration with international partners, including knowledge exchange, and research cooperation.

The PFBR project has stimulated economic growth through investments in infrastructure, development of novel manufacturing technologies and creation of highly skilled workforce. A robust nuclear energy ecosystem in India, created by PFBR, harmonised contributions from R&D organisations, researchers, material scientists, intricate equipment manufacturers and highly skilled installation and commissioning teams.

Handling, storage and transfer of 1,950 metric tonne sodium without spilling a single drop, speaks volumes about competence of fast reactor teams at Kalpakkam. India's achievements in fast breeder technology showcases the country's potential to become global leader in thorium technology landscape.

Fast breeder reactors operate under extreme conditions of temperature, pressure, and radiation, requiring advanced materials that can withstand these conditions. Developing and qualifying materials for reactor components, including structural materials, cladding, and fuel elements, have been a technological challenge.

The Indian industry has played a significant role in producing materials to stringent specifications and manufacturing and fabrication of equipment for the PFBR project. Almost all the materials for the fabrication of PFBR have been manufactured by Indian companies.

Indian engineering firms have provided design, engineering, and consultancy services for this project. This includes the development of detailed engineering designs, safety analyses, and quality control measures. Young PFBR team took up challenging construction, commissioning and quality assurance responsibilities.

Indian thermal neutron reactors built by Nuclear Power Corporation of India Limited had increased the quality production capabilities of Indian industries over the decades. PFBR required enhanced competence from industries for its equipment which are much larger in dimension and required far more stringent specification and tolerance control.

Large thin walled Safety vessel, Main vessel and Inner vessel required stringent safety design and fabrication capabilities, have been fabricated by Larsen and Toubro and BHEL at PFBR construction site, since these were too large to be transported by road.

Never in the past were such large thin walled vessels fabricated in India. Thin walled Inner vessel made by BHEL, required critical control of dimensional tolerances in complex geometry.

It is worthwhile to mention that the experience of Safety and Main Vessel fabrication for PFBR provided an opportunity to Larsen and Toubro to fabricate yet another large size thin walled vessel at ITER (Fusion reactor project at France, a project to create fusion in a large tokamak and create temperatures ten times the temperature of the Sun).

The cryostat, a stainless steel vacuum pressure vessel weighing 3,850 tonnes and of 30 metres in diameter is the largest vessel ever made in the world. It has glorified India's manufacturing capabilities before the world.

Kirloskar Brothers Limited (KBL) came forward to take on the highly challenging task of design and manufacture of primary and secondary sodium pumps. They have to circulate liquid sodium at temperatures over 500 degrees. Primary sodium pump has an 11 metre long shaft. The secondary sodium pump has hydrodynamic bearings. Since the pumps operate in a sodium environment, they have to be almost maintenance free.

It took knowledge, skills and courage by KBL team to accept the order for these pumps. KBL has demonstrated that Indian industries can take up any challenge.

MTAR Technologies undertook the manufacture of inclined fuel transfer machine and reactor top control plug. WalchandNagar Industries manufactured large sodium-to-sodium and sodium-to-air heat exchangers. Sodium-to-water heat exchanger/steam generators were made by Larsen and Toubro. All these entities created specialised clean room facilities to undertake manufacture of critical PFBR equipment.

Tata Consulting Engineers (TCE) supported PFBR in design details and Gammon India undertook civil and structural works requiring great precision. Power Island equipment were manufactured by BHEL.

Various units of Department of Atomic Energy including Nuclear Fuel Complex, Electronics Corporation of India Ltd, Heavy Water Board etc took up challenging responsibilities. IGCAR manufactured many critical equipment in its workshop and dedicated many of its labs and test loops for testing and qualification for PFBR equipment.

PFBR had to pass through some rough patches during its construction and commissioning.

The Tsunami on December 26, 2004, had destroyed the project completely. Restart of the construction required a fresh safety review involving expertise of various centres of knowledge in geology, seismology, oceanography, meteorology etc. Design changes and raising the garage level of the PFBR had an impact on cost and time of the project.

The Fukushima accident in Japan on March 11, 2011 required every nuclear facility in the world -- under construction or in operation -- to have a fresh review of safety in the background of new knowledge that came forth by the Fukushima accident. This, too, required back fitting of a few new features in PFBR, and thus impacted the cost and time.

It has been noted that wherever ambitious mega projects to create new technologies are launched, despite the best risk management features in place, challenges beyond expectation are faced during construction and commissioning. These, beyond planning events, have resulted in delays and cost escalation.

Despite best planning, best brains involved, extensive testing and qualification programmes, and most meticulous construction and commissioning practices adopted, many first of this type of projects in the world have experienced issues beyond original risk evaluation. ITER, France is one such example.

In PFBR the design, equipment fabrication and construction have been undertaken simultaneously. To put an end to design refinements, DAE had taken one of the most appropriate decisions to launch PFBR in October 2003, and asked designers, equipment manufacturers, construction personnel to work together to manage the complex technology and establish safety protocols.

It may also be appropriate to mention that for the fast breeder reactors, the regulatory framework and safety principles were not fully developed by the Atomic Energy Regulatory Board when the PFBR was launched. Many of the safety rules were prepared parallelly during construction of PFBR. This, too, had little impact on pace of construction.

Fast reactors are extremely complex. Presence of a huge amount of sodium adds to the complexities in design, construction, commissioning and maintenance.

Fast breeder power reactor programmes were launched only by four countries. These are France, Japan , Russia and India. France and Japan have shut down their reactors due to sodium leak and associated fire. Both France and Japan and are currently going slow with their plans till generation four features are implemented. Russia is the only country operating the fast breeder reactor. India has introduced many generation four features in PFBR after the Fukushima accident, and is pursuing the fast breeder reactor programme with robust design and technological backbone existing now in the country.

In 2003, when the PFBR project was launched by BHAVINI, only a few experienced personnel were available on deputation from IGCAR, who had knowledge of fast breeder reactor design and operation of FBTR. BHAVINI had to appoint fresh engineering graduates and initiate a major training and qualification programme for the freshers to manage the complex and first of its type fast reactor technology for PFBR. This was an initial hiccup which was later fixed.

IGCAR and other units of DAE have been involved in skill development, training and qualification programmes for personnel working in the PFBR project. The training in FBTR includes providing specialised skills and preparing the operation teams to get PFBR operation licence from AERB.

As time passed, BHAVINI engineers got recognised as one of the most competent, committed and hard working professionals.

(Dr Prabhat Kumar is former CMD of BHAVINI.)