Fahrenhorster Weg 55
22889 Tangstedt 

T: +49 (0) 4109 2787-16
E: info (at)


Christoph Schmitt

Managing Director solar-konzept gmbh
Managing Director solar-konzept International gmbh 


Christoph Schmitt studied industrial engineering at the Nordakademie in Elmshorn. From 1999 to 2006 he built up the Major Projects division at BP Solar, one of the world’s largest solar energy companies.

From 2006 to the beginning of 2009 he was responsible for project development in the photovoltaic sector at Epuron GmbH, and ubsequently at Conergy AG. In May 2009 he joined solar-konzept gmbh as Managing Director.

Karen Kedziora
Managing Director solar-konzept gmbh 

After practical training as an assistant tax advisor and studies in Mathematics and Physics at the Free University of Berlin and the University of Hamburg, Karen Kedziora joined solar-konzept gmbh in 2004. In 2006 she was appointed Managing Director.



Isekai 1
20249 Hamburg 

T: +49 (0)40 3989 59-10
E: c.schmitt (at)

info (at)


Birgit Eggl

Head of Business Netherlands, development Europe


After completing a master's degree in environmental sciences and working at a consultancy for finance and investment in renewable energies for a couple of years, Birgit Eggl was employed by the Hamburg-based solar company Conergy for 8 years. Since 2013 she has been responsible for the UK market from the Milton Keynes branch and has implemented a pipeline with over 350 MWp with her team.

Since mid 2015 she lead all project development activities and the EPC business in the EMEA region, with a focus on Europe. As part of the solar-konzept group, she is now responsible for the Dutch project business together with Martin Voigt. She is a shareholder and manager of TPSolar-konzept as of January 2017.


Martin Voigt
Head of Business Netherlands, development Europe

After studying industrial engineering at Jena University of Applied Sciences, Martin Voigt worked for the Conergy Group from 2005 to 2010 in the national and international large-scale projects. In 2011, he became self-employed and supported various companies in the realization of large-scale projects and in the development and evaluation of new business models. From 2012 to 2015 Martin Voigt, a managing partner with Grünstromwerk, built a new energy supplier, which was integrated into the Naturstrom Group in 2015.


In 2016 Martin Voigt worked briefly for the Aquila Group and joined solar-konzept gmbh in September, now responsible for the Dutch project business together with Birgit Eggl. He is a shareholder and manager of TPSolar-konzept as of January 2017.

Our JV partners in the Netherlands


TPSolar B.V.

TPSolar-Konzept B.V.


Melbournestraat 9
1175 RM Lijnden


T: +49 (0)40 3989 59-12

E: info (at)


Erik Wieffer

Managing Director / Managing Director TPSolar BV   

After studying sales and marketing in Amsterdam, Erik Wieffer worked from 1991 to 2000 for various Dutch manufacturing companies of metal products and drinking water installations.

From 2000 to 2010 he worked as a senior manager for CRH PLC (BIK Bouwprodukten BV) and Saint Gobain Glass Solutions in roofing installations and building glass. As of 2010 Erik Wieffer has been active in the solar glass industry and solar industry in the Netherlands.

In 2015 he founded TPSolar BV with Rene Hendriks. He is a shareholder and manager of TPSolar-konzept as of January 2017.

Rene Hendriks

Managing Director / Managing Director TPSolar BV   

After studying Economics at Vrije Universiteit Amsterdam, Rene Hendriks worked for Saint-Gobain from 1991 to 2005. He started at Isover SGG and after 4 years moved to Saint-Gobain Glass. He pursued several roles in the senior management before leaving SGG to join a medium sized business in glass as co-owner in 2005. He started the sales of solarglass in 2006 providing him a valuable insight into the solar industry.


He successfully sold solarglass all over Europe to solarpanel producers gaining extensive experience in project sales and development both national and international. At the end of 2015 he formed TPSolar together with Erik Wieffer and is a shareholder and manager of TPSolar-konzept as of January 2017.

Birgit Eggl

Managing Director

Martin Voigt
Managing Director


Nikolaus von Einem

Managing Director solar-konzept International

Nikolaus von Einem studied environmental sciences at the Swiss Federal Institute of Technology in Zurich. Since 2005 he has developed photovoltaic projects for various companies. 

In 2007 he established and was head of EPURON Italia, responsible for the project business of the Conergy group in Italy. In 2008 he took over the management of solar-konzept italia srl.


Galleria Vintler 17
39100 Bolzano

T: +39 (0) 340 919 61-55
 E: info (at)



Andrea Christini
Managing Director solar-konzept Italia srl

After his graduation in mechanical engineering Andrea Christini gathered an eleven years expertise in project development of national and international renewable energy projects.

For over 12 years he performed as a Managing Director and Country Manager, responsible for the international project development in Italy and EPC business.


For the past six years he has been a Managing Partner in Italy responsible for 10 projects with 40 million of sales before he joined solar-konzept for the Italian market.




47 Vouliagmenis Avenue, Eliniko

16777 Athens



T: +30 211 01 6838
E: g.tzanidis (at)

George Tzanidis

Managing Director solar-konzept Greece

Following his studies in mechanical engineering from City University in London and a master’s degree in business administration from Leicester University, George Tzanidis started his professional career in 2001 with EDF Energy as a derivatives trader. In 2004 he joined BP as a member of the commercial and retail management team. In 2008 George decided to enter the field of renewables with BP Solar.


Following his departure from BP in 2010 he worked for three international energy companies, SunEdison, Conergy and Hanergy overseeing project development activities and the implementation of commercial strategies in the region of South East Europe. He is a shareholder and manager of solar-konzept Greece as of March 2018.