This book comprises selected proceedings of the ThEC15 conference. The book presents research findings on various facets of thorium energy, including exploration and mining, thermo-physical and chemical properties of fuels, reactor physics, challenges in fuel fabrication, thorium fuel cycles, thermal hydraulics and safety, material challenges, irradiation experiences, and issues and challenges for the design of advanced thorium fueled reactors. Thorium is more abundant than uranium and has the potential to provide energy to the world for centuries if used in a closed fuel cycle. As such, technologies for using thorium for power generation in nuclear reactors are being developed worldwide. Since there is a strong global thrust towards designing nuclear reactors with thorium-based fuel, this book will be of particular interest to nuclear scientists, reactor designers, regulators, academics and policymakers.

A.K. Nayak, a graduate in Mechanical Engineering from NIT, Rourkela, India, is currently working at Reactor Design and Development Group in BARC since 1990 after completing a one-year Orientation Course in Nuclear Engineering from BARC Training School, Mumbai, India. He obtained his PhD in Nuclear Engineering from Tokyo Institute of Technology, Japan in 2000. He worked at Interfaculty Reactor Institute, Technical University Delft from 2002-03 and at the Nuclear Power Safety Division, Royal Institute of Technology, Stockholm from 2003-04 as Post-doctoral Scientist in the field of design of natural circulation based reactor systems and severe accident. He worked at the Institute of Nuclear Energy (IKE), University of Stuttgart, Germany during 2009-10 in the DST-DAAD project on "Debris Coolability in Severe Accident". He has received several awards which include the DAE Scientific and Technical Excellence Award in 2006, DAE SRC Outstanding Research Investigator Award in 2010 and the Homi Bhabha Science and Technology Award in 2014. He has published more than 250 papers in academic journals and at conferences. His research contributions include nuclear Advanced nuclear reactor design, thermal hydraulics and safety, particularly in the context of severe accident. He served as Guest Editor of Nuclear Engineering and Design Journal, SADHANA Journal and ASME Journal of Nuclear Engineering and Radiation Science. He is Editor-in-Chief of Journal "Multiphase Science and Technology" and Associate Editor of the Journal "Frontiers in Energy". Currently he is Head, Thermal Hydraulics Section, Reactor Engineering Division, BARC and Professor, Homi Bhabha National Institute, India.

Bal Raj Sehgal is currently Professor Emeritus of Nuclear Power Safety at the Royal Institute of Technology, Stockholm, Sweden. Previously, he was Chair Professor at the same institution from December 1991 to December 2004. Prof. Sehgal came to Sweden from the University of California Berkeley, where he was Professor in Residence and concurrently worked at EPRI, where he was Senior Technical Advisor and Senior Program Manager for 18 years. Prof. Sehgal spent a year as a Visiting Professor at Purdue University and M.I.T. in 1973 and 1980, respectively. Prior to his employment in California, Prof. Sehgal worked at Argonne and Brookhaven National Laboratories. Since the TMI-2 accident, his main area of interest has been LWR severe accidents. Prof. Sehgal is a foreign member of the Royal Swedish Academy of Engineering Sciences and the Lithuanian Academy of Sciences. In 2013 he was elected as a member of the U.S. National Academy of Engineering. He is Fellow of the American Nuclear Society (ANS) and the American Society of Mechanical Engineers (ASME). He has received the Laurence Pioneering Award, the Seaborg Medal, the Tommy Thompson Reactor Safety Award, and Thermal-Hydraulic Technical Achievement Award from the American Nuclear Society. He also received the Thermal Hydraulics Fellow Award from the Thermal Hydraulics Division of the American Nuclear Society in 2013 and the Swedish Risk Academy Award for 2015. Prof. Sehgal has published more than 380 papers during his career.