For more information, contact:

Mike El-Hillow Advanced Energy Industries, Inc. 970.407.6570

Cathy Kawakami Advanced Energy Industries, Inc. 970.407.6732 cathy.kawakami@aei.com

Fort Collins, Colorado (July 22, 2004)—Advanced Energy (Nasdaq: AEIS) today announced the appointment of Dr. Hans-Georg Betz, 58, to the Board of Directors. Dr. Betz has over thirty years of experience in the electronics industry. He is currently chief executive officer of West STEAG Partners GmbH, a German-based venture capital company focused on the high technology industry. Previously, he was chief executive officer of STEAG Electronic System AG and a Managing Director at Leybold AG.

Doug Schatz, chairman and chief executive officer said, “Dr. Betz is a well-respected member of the semiconductor community based on his meaningful contributions as a technologist and business leader. His executive and scientific experience, especially in the international community, provides a new important dimension to our Board as we continue our drive to expand our operations around the world.”

Dr. Betz currently serves as a board member for high-technology companies such as Mattson Technology, GuideTech and Photodigm.

About Advanced Energy
Advanced Energy is a global leader in the development and support of technologies critical to high-technology manufacturing processes used in the production of semiconductors, flat panel displays, data storage products, compact discs, digital video discs, architectural glass, and other advanced product applications. Leveraging a diverse product portfolio and technology leadership, Advanced Energy creates solutions that maximize process impact, improve productivity and lower cost of ownership for its customers. This portfolio includes a comprehensive line of technology solutions in power, flow, thermal control and plasma and ion beam sources, for original equipment manufacturers (OEMs) and end-users around the world.

Advanced Energy operates in regional centers in North America, Asia and Europe and offers global sales and support through direct offices, representatives and distributors. Founded in 1981, Advanced Energy is a publicly held company traded on the Nasdaq National Market under the symbol AEIS. For more information, please visit our corporate website: www.advanced-energy.com.