The energy crisis of the 1970s, as well as the proliferation of nuclear weapons and nuclear power plants (and related civilian concerns regarding these technologies) led to the creation of the Department of Energy as the 12th Cabinet-level federal agency. The Department of Energy Organization Act of 1977 consolidated several Federal energy agencies under one organizational structure. Today, the Department aims to create and implement a national energy plan, regulate energy prices, support America's independence from foreign sources of energy, and promote research and safety.
Now considered one of the least attractive federal buildings, (along with other Brutalist structures built during this same era like the Hubert Humphrey Building and the J. Edgar Hoover Building) the exterior of the Forrestal Building features pre-cast concrete units. Brutalism was an architectural style of the 1950s and 1960s characterized by concrete cast in block-like forms. As one might expect given the current occupant, the Forrestal Building has been upgraded to include numerous energy-efficient features and is powered partially by one of the largest solar arrays in the city.