ista International Management

Thomas Zinnöcker

Chief Executive Officer

Thomas Zinnöcker, born in 1961, became the CEO of ista in March 2016. Before, he held various management positions in the real estate industry. As the Deputy CEO of Vonovia SE, he was responsible for the successful integration of the GAGFAH Group, where he had been the CEO since 2013. Prior to that, he had headed GSW Immobilien AG for eight years. Thomas Zinnöcker studied business administration at the University of Cologne.

Achim Dicke

Chief Technology Officer

Achim Dicke, born in 1964, has been the CTO of ista since July 2018. Previously, he was the Senior Vice President of the Products division. In a career with ista spanning over 28 years, he has worked for the company in the fields of product development, engineering, quality management, product management and materials management. Achim Dicke studied electrical power engineering at University GH Paderborn.

Ulrich Fischer

Managing Director Global & Developing Markets

Ulrich Fischer, born in 1966, became the Managing Director Global & Developing Markets at ista in October 2017. He has valuable experience in the global submetering business, having held several management positions at ista and its predecessors Viterra and Raab Karcher Energy Services. From 2009 to 2011, he was a member of the board at Techem Energy Services. Ulrich Fischer studied Supply Engineering/ Energy Management in Esslingen a. N. and Sydney.

Frank Jung

Chief Financial Officer Global & Developing Markets

Frank Jung, born in 1971, is the CFO Global & Developing Markets at ista. He joined the company in 2010 as Treasurer & Senior Controller and later became Regional CFO. Having started his career at Dresdner Bank, he held positions in corporate and investment banking and corporate development. Subsequently, he worked for six years in M&A advisory at Deloitte. Frank Jung studied business administration at the University of Cologne.

Karl Kornwolf

Chief Information Officer

Karl Kornwolf, born in 1967, started at ista in January 2019. In a career spanning more than twenty years, he transformed a cable Cable TV operator from “analog to digital” and the IT and Innovation Unit of Deutsche Telekom AG from “mobile to cloud”. Prior to ista, he initiated the IoT services business for Siemens – from “hardware to services”.

Thomas Lemper

Chief Financial Officer

Thomas Lemper, born in 1974, was appointed the CFO of ista in June 2018. Previously, he was the Senior Vice President of Corporate Controlling & Treasury. From 2012 until 2014 he was the CFO of the former ista branch in the United States. Before joining ista in 2006 as Head of Controlling for the Central Region, he held various finance positions at Lufthansa. Thomas Lemper studied business administration in Münster.

Benny Mathiesen

Country Manager Nordic Countries

Benny Mathiesen, born in 1966, has been the Country Manager for Denmark and Regional Manager for the Nordic Countries since 2006. In addition, he became a member of the International Management in July 2018. He started his career in 2003 as Director of Clorius Varmemålerkontor I/S, a subsidiary of ista Danmark A/S. Through previous positions, he gained extensive experience in the energy business. Benny Mathiesen holds a M. Sc. in Material Engineering from Loughborough University of Technology.

Jörg Plönissen

Country Manager Netherlands

Jörg Plönissen, born in 1961, has been the Country Manager for the Netherlands since 2004 and a member of the International Management since July 2018. He has valuable experience in ERP solutions and cash management for the utility and retail industries. In 2013, he became Chairman of the NLVVE, the Dutch association for the submetering market. Before starting his career, Jörg Plönissen was trained in industrial management.

Laurent Sireix

Country Manager France

Laurent Sireix, born in 1967, became the Country Manager for France in 2005. Since October 2017, he has also been a member of the International Management. He has wide-ranging experience in the energy industry, having held several management positions: e.g. he was Managing Director of Gaz France at Schlumberger. He joined ista in 2004 as Director of Operations. Laurent Sireix has studied at the prestigious French “Ecole Nationale Superieure des Arts & Métiers”.