The Department of Energy's mission is to foster a secure and reliable energy system that is environmentally and economically sustainable; to be a responsible steward of the Nation's nuclear weapons; to clean up the Department's facilities; to lead in the physical sciences and advance the biological, environmental, and computational sciences; and to provide premier scientific instruments for the Nation's research enterprise.
The Department of Energy (DOE) was established by the Department of Energy Organization Act (42 U.S.C. 7131), effective October 1, 1977, pursuant to Executive Order 12009 of September 13, 1977. The act consolidated the major Federal energy functions into one Cabinet-level Department.