About us

We add sustainable value to buildings for their residents and owners. To achieve this, we manage data and processes that make the building climate-friendly, safe and comfortable.

Benefits for owners and residents

Our data-based products and services make individual energy consumption transparent to residents so they can save energy, costs and CO2. This in turn makes it easier for the owner to increase energy efficiency and therefore the value of the property. So residents and owners together actively contribute to climate protection. In average every household saves 20 % of its annual heat consumption and costs. Every year some four million tonnes of CO2 emissions are avoided by our customers and their tenants in Germany alone.

Technology wins

Our product and service world is digital-based. Our device infrastructure makes smooth data-based building data management possible, doing away with traditional on-site reading of energy meters in particular. This increases convenience for residents and owners as it dispenses with meter-reading appointments and waiting times and reduces data and process management times. Our digital infrastructure can also be used for other applications, such as digital smoke alarm devices which can be remotely serviced, therefore increasing residents' safety.

One step ahead

Today, we are already making our product and service world fit for the Internet of Things. In the near future, billions of smart devices will communicate directly with each other. As a driver of innovation in our industry, we are therefore systemically gearing our building infrastructure to be IoT-capable. So we are already in a position today to develop solutions and use cases with our customers for the intelligent building of tomorrow.

ONE ista

'We', that is the over 6,000 ista employees in 22 countries. We are all united by the desire to become THE partner for digitisation and smart solutions for building owners and their residents. We want to go down this path to the future together with the worldwide 450,000 owners and 13 million residents, in whose buildings and apartments our products and services are used today.






Facts & Figures

  • 5800
  • 0
  • 0m t CO2
    emissions avoided in Germany
  • 31000999
    connected devices
  • 5999925
  • 12999925
    residential and commercial units




Hagen Lessing


Dr. Hagen Lessing, born in 1973, became the Country Manager of ista Germany in October 2019 and in June 2021 Chief Executive Officer of the ista Group. Before, he has worked for more than 15 years for the Boston Consulting Group, since 2013 as a managing director and partner. Hagen Lessing studied Business Management and Engineering in Cottbus and Ohio, in 2004 he received a PhD from the Faculty of Business Administration and Economics at the University of Paderborn.

Michaela Hitzberger


Michaela Hitzberger, born in 1981, started as Head of Board Office at ista Germany in February 2020. Since April 2021 she has been Head of Corporate Strategy and since January 2022 a member of ista Group Market Board. Previously, she worked for more than 14 years in management consultancies, including AFRY Management Consulting and KPMG. Michaela Hitzberger studied business administration at the University of Bamberg and at the University of Jyväskylä.


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.


Country Manager Northern & Eastern Europe

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.


Country Manager Netherlands & Belgium

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.

Oliver Schlodder

Head of Commercial & Industrial and Focus Markets

Oliver Schlodder, born in 1980, is responsible for the Commercial & Industrial and Focus Markets division of the ista Group since July 1, 2021. The graduate in Business Administration has already been Head of Commercial & Industrial and a member of the Management Team at ista Germany since November 2020. His previous positions include Executive Vice President and member of the Group Leadership Team at NKT A/S, a global provider of cable solutions. Prior to that, he also advised companies in the energy and industrial goods sectors at the Boston Consulting Group.


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”.