UniSource Energy Announces New Vice Presidents, One Retirement.

TUCSON, Ariz. -- James S. Pignatelli, Chairman, President and CEO of UniSource Energy Corporation (NYSE: UNS), announced that the company's Board of Directors has named four new vice presidents who will assume their positions beginning in 2007.

Kentton C. Grant, 48, has been promoted to Vice President of Finance and Rates. Grant has served as Assistant Treasurer and General Manager of Financial Planning for Tucson Electric Power (TEP), UniSource Energy's principal subsidiary. He will be responsible for corporate financing activities, financial planning and rate case preparation for TEP and its sister utilities, UNS Electric and UNS Gas, which do business under the name of UniSource Energy Services (UES).

Arie "Andy" Hoekstra, 58, has been named Vice President of Generation. Hoekstra, who has served as TEP's General Manager of Energy Resources, will oversee the company's power production operations.

David G. Hutchens, 40, has been named Vice President of Wholesale Energy and UNS Gas. Hutchens has served as TEP's General Manager of Energy Resources. His responsibilities will include management of wholesale energy acquisition and sales as well as UniSource Energy's natural gas operations.

Thomas A. McKenna, 58, has been promoted to Vice President of Engineering and UNS Electric. McKenna, who has served as Manager of Project Development for TEP, will oversee engineering at TEP and the operations of UNS Electric.

"All four of our new corporate officers have distinguished themselves with exemplary performance at TEP," Pignatelli said. "They've been key contributors to many of our recent accomplishments, and I expect them to contribute significantly to this company's future success."

Tom Hansen, currently Vice President and Technical Services Advisor, will assume the title of Vice President of Renewable Energy and Conservation Services.

Senior Vice President Dennis Nelson, Chief Operating Officer of UES, has announced his plans to retire effective June 1, 2007. Nelson joined TEP in 1976 and previously served as UniSource Energy's General Counsel.

"Dennis has devoted more than three decades of valuable service to this company," Pignatelli said. "His leadership has been a real asset, particularly as we have integrated the operations of UNS Electric and Gas over these past few years. We're going to miss him."

UniSource Energy's primary subsidiaries include TEP, which serves approximately 389,000 customers in southern Arizona; and UES, provider of natural gas and electric service for approximately 235,000 customers in northern and southern Arizona. For more information about UniSource Energy and its subsidiaries, visit uns.com.