Ernest Moniz was born in Fall River, Massachusetts, in 1944. He graduated from Boston College with a degree in physics in 1966 and then received his PhD in theoretical physics from Stanford University in 1972. The following year, he joined the faculty of the Massachusetts Institute of Technology (MIT). At MIT, Moniz became the Cecil and Ida Green Professor of Physics and Engineering Systems. He also directed the MIT Energy Initiative, which combines research, education, and policy focused on energy supply, security, and environmental impact.

Moniz served as associate director for science in the Office of Science and Technology Policy in the Executive Office of the President from 1995 to 1997. He was also undersecretary at the Department of Energy from 1997 to 2001.

In 2009, President Barack Obama appointed Moniz to the Science and Technology Advisory Council. President Obama nominated Moniz to be secretary of the Department of Energy in March 2013. He was confirmed by the U.S. Senate in May 2013. As secretary, Moniz pledged to explore alternative forms of energy such as nuclear energy to meet the country's energy needs while also working to increase energy efficiency and combat global warming.