1. Ph.D. Student, Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz khas, New Delhi 110016, India.
2. Emeritus Professor, Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz khas, New Delhi 110016, India (corresponding author).
3. Professor, Dept. of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-khas, New Delhi 110016, India.