In India, nuclear energy development began with the objective of peaceful uses of atomic energy in improving the quality of life of the people and to achieve self-reliance in meeting the energy needs. The atomic energy program, which was initiated in a modest manner initially, has now grown as a wide spectrum, multi-dimensional multi-disciplinary with 63 organizations under DAE.

Apsara was the first research reactor in Asia to achieve criticality in1956 at BARC. It was a pool type reactor of 1 MW power with highly enriched uranium and Light water was used as both moderator and coolant. APSARA has been successfully Upgraded. Dhruva is a 100 MWth research reactor, completed more than three decades of operation.

Dr. Sujay Bhattacharya a Distinguish Scientist and Director, Reactor Projects Group, joined BARC in 1984 after a one-year training in Nuclear Engineering.

He was posted to the Reactor Projects Division of BARC for the design of the core components of a compact Light water reactor for strategic use and later joined to the PRP, Kalpakkam in 1989. After completion this, he became the head of Projects at Uranium Extraction Division in 2007, for the Design and Commissioning a re-engineered Uranium Metal Plant to augment the increasing demand for Uranium metal. In 2011, he successfully designed and commissioned a Uranium Metal Refining and Effluent Handling Plant with added safety and modern instrumentation after resolving various problems encountered in special equipment meant for purifying raw uranium to nuclear grade pure uranium metal.

In 2013, he joined the Reactor Group as head of the Research Reactor Design and Projects Division.  Under his supervision, APSARA Reactor was successfully Upgraded, constructed, and operated in 2019. In 2016, he became the Associate Director, Reactor Group and contributed to the achievement of sustained operation of Dhruva at 100 MW for the first time since its inception in 1984.

He became the Director, Reactor Projects Group, BARC in 2018.

He was also involved as a Project Coordinator for the new Nuclear facility at Vizag.

He made notable contributions to our TBM program in ITER by guiding our scientists and engineers in various critical design and fabrication areas, which helped us very much in the CDR of LLCB TBM.

He has authored more than 15 article in peer reviewed national and international journals. He is the recipient of many awards including:

DAE Group Achievement Award for PRP in 2006;

Special Contribution Award for PRP in 2007;

DAE Group Achievement Award for the development and commissioning of a re-engineered uranium metal plant and uranium metal refining in 2012;

DAE Group Achievement Award for Development and Commissioning of New Hydro-Processing Facility in 2014;

Homi Bhabha Science and technology award in 2019.