His Excellency Rear Admiral Gbenah was born on 21st August, 1946 at Kpedze in the Volta Region of Ghana. He attended Mawuli Secondary School, Ho, and proceeded to the University of Ghana, Legon, for a BSc Administration Degree. He has a Diploma in Journalism, a Certificate in International Humanitarian Law and a Post Graduate Diploma in Defence Resources.

His Excellency Rear Admiral Gbenah has served in various capacities in the Ghana Military. In 1989, he was Naval Officer -In-Charge of the Eastern Naval Command, Tema. He then became the Acting Director General of Personnel Administration and later Chief Staff Officer at the Navy Headquarters. He has also worked as Resource Personnel (Class Leader) International Military Course on Law of Armed Conflict, Institute of Humanitarian Law, San Remo, Italy, on five occasions.

In June, 1996, he was Defense Advisor, India and then Flag Officer Commanding, Western Naval Command, in December 2000. He served as Chief of Navel Staff, Ghana Navy, from March 2001 to May 2005, and in February 2006, was appointed Ambassador to the Republic of Zimbabwe.

He is married, and enjoys reading, sailing, country camping and meditation.