Energy Department vs Department of Energy

Energy Department and Department of Energy both are nouns.

Word	Noun	Adjective	Verb	Adverb
Energy Department	Yes	No	No	No
Department of Energy	Yes	No	No	No

As nouns, Energy Department and Department of Energy are synonyms defined as:

Energy Department and Department of Energy: the federal department responsible for maintaining a national energy policy of the United States; created in 1977

Other synonyms of Energy Department include DOE, Energy.

Energy Department (noun)	Department of Energy (noun)
the federal department responsible for maintaining a national energy policy of the United States; created in 1977	the federal department responsible for maintaining a national energy policy of the United States; created in 1977