Based in the UAE, Siersdorfer joined Siemens in 1987 in Mannheim, Germany, as an electrical engineer and held various managerial positions in the Industry and Energy sectors during his tenure at the company.
For two years, starting 1997, he was located at the Siemens Southeast Asia headquarters in Kuala Lumpur, Malaysia, promoting the Industry Sector’s Digitalization business in the region. In 2001, Siersdorfer took over the global responsibility for Manufacturing Execution Systems within Siemens AG in Erlangen, Germany. In this position he focused on digital plant optimization, covering a wide range of industries, including oil and gas, food and beverage, power generation, chemicals, automotive, and manufacturing on a global scale and particularly in the Americas, Asia Pacific and Europe.
In 2004, he was appointed Executive Senior Vice President for fossil power generation for Europe, Africa, Middle East and India. Two years later, he became President and CEO of the global fossil energy solutions business within the Siemens Power Generation division.
Siersdorfer is an active board member of a number of Siemens subsidiaries, including Siemens Electrical and Electronic Services, K.S.C.C, Kuwait; Siemens LLC Oman; Siemens SSK Iran; and Siemens WLL Qatar and Siemens Egypt SA. He has also held board positions for Siemens Ireland; Siemens Pakistan Engineering Company Ltd. and ISCOSA Industries and Maintenance Ltd., Riyadh/Saudi Arabia.
In his free time, Siersdorfer enjoys golfing, jogging and music in a great variety.