* Chavez named Carrizalez as vice president in 2008
* Environment minister also quits for personal reasons (Recasts, adds details, background)
CARACAS, Jan 25 (Reuters) - Venezuela's Vice President Ramon Carrizalez, who was also defense minister, resigned on Monday citing personal reasons, adding to the political problems facing leftist President Hugo Chavez.
Chavez is facing growing discontent over shortages of electricity and water and sharply devalued the currency this month. He is preparing for elections in September that could reduce his tight grip of the OPEC nation's parliament.
Chavez named the soft-spoken Carrizalez to the number two job in 2008, and in 2009 appointed him him to simultaneously serve as defense minister.
State-backed news network Telesur reported that Carrizalez' wife, Environment Minister Yuviri Ortega, also resigned. Carrizalez denied the resignations had to do with differences with the government, Telesur reported.
A government official confirmed the information but did not provide details.
Carrizalez, a close Chavez confidant who is a former army officer like the president, was seen as one of the government's more capable administrators.
This month Chavez fired a recently named electricity minister for botching a Caracas electricity rationing scheme.
He has also changed his finance minister, Ali Rodriguez, who he named new electricity minister this month. Left-wing academic Jorge Giordani took over the finance ministry.
Carrizalez previously served as infrastructure minister and housing minister. He took on some of the nation's thorniest problems including its acute housing deficit and the 2006 collapse of a crucial bridge linking Caracas to the airport and its main port.
Chavez named Carrizalez vice president just after his first-ever ballot box defeat in a constitutional overhaul referendum in 2007, replacing the combative Jorge Rodriguez. (Reporting by Caracas Newsroom; Writing by Brian Ellsworth; Editing by David Storey)