Smart people, a wealth of knowledge, and the spirit of innovation –
that's what we've been about for more than 30 years.

About us


We are a small, independent and interdisciplinary team of experts, and our main area of expertise is in photovoltaics. We develop projects, advise companies and authorities, and continually produce innovative ideas that we see through to fruition. We do not sell any products, and instead of provide services in form of consulting, planning and project support. We also engage in information, training and lobbying work in the fields of energy efficiency and renewable energies.

The photovoltaic segment has seen massive development in the past 25 years – since TNC was founded – and its future potential is still far from being exhausted. We do our part to make suer this potential is harnessed to the full.

We are strong

The TNC and Effienergie AG team consists of engineers, architects, energy consultant, and specialists in photovoltaic systems, building renovation and metrology. Together, we have many decades of experience, and we bring a passionate commitment to renewable energies to each new project.

Thomas Vontobel

Telefon +41 (0)58 680 20 17

Dipl. El.-Ing. FH, Managing Director TNC Engineering AG. More

Ralph Lingel

Telefon +41(0)58 680 20 14

As a Dipl.-Ing. Maschinenwesen Ralph Lingel is main-responsible for the TNC project development TNCALL.


Nadine Kunz

Telefon +41 (0)44 991 55 77

Since 2012 Nadine Kunz is responsible for accounting and HR matters at TNC and Effienergie AG.

Stephanie Fehling

Telefon +41 (0)58 680 20 19

Since 2003, she is the assistant of the CEO, handles the coordination and organization of various tasks at TNC, communication and webmaster. She ist member of the board of directors of Effienergie AG and TNC Engineering AG. She is responsible for the office of the Zürichsee Solarstrom AG and care of the shareholders.

Thomas Nordmann

Telefon +41 (0)44 991 55 77

Company founder, CEO, and the driving force and soul of TNC. A photovoltaic pioneer from the very outset. Thomas Nordmann (born in 1952) has been working in the field of solar power since 1974. He es the founder and CEO of TNC Consulting AG and chairman of the Board of Directors of Effienergie AG.


Loris Casura

Telefon: +41 (0)58 680 20 16

BSc Energy and Environmental Engineering (FH)
Since October 2020 PV Project Engineer.

Roberto M. Borsotti

Telefon +41 (0)58 680 20 24

MSc ETH Masch.-Ing.
Seit 2023 bei TNC Consulting AG für Projekt- und Geschäftsentwicklung tätig.

Anthony Di Blasi

Telefon +41 (0)58 680 20 23

MSc in Engineering, Vertiefung Energy & Environment
Seit 2023 als Projekt-Ingenieur für die PV Projekte der TNC Engineering AG.

We are well connected

TNC is part of a close-knit network of various companies and activities.

Effienergie AG

Effienergie AG, a fully owned subsidiary of TNC, focusses on the issue of energy efficiency on buildings.



Die Zürichsee Solarstrom AG (ZSSAG) is the first solar power network around Lake Zurich, and constructs large solar systems on the roofs of a wide range of buildings in the region


Egon AG

TNC is one of the founders an shareholders of Egon AG. The company’s name comes from the German “Energie im Gebäude online” – “energy in buildings online”.


International Energy Agency, IEA

The International Energy Agency IEA is a cooperation platform in the field or research, development, marketing and implementation of energy technologies. Thomas Nordmann heads a working group looking at the performance and reliability of PV systems.


Forum Energiespeicher Schweiz FESS

TNC is partner of the 2016 newly founded “Forum Energiespeicher Schweiz FESS”. Thomas Nordmann is head of the core team and spokesman of the economy.



TNC is Solarprofi® at Swissolar

Solarprofis are qualified experts who advise and assist in the realization of solar power systems.

Solarprofi companies are carefully examined by Swissolar for their training and practical experience. The quality lable “Die Solarprofis” is also supported by EnergieSchweiz.


25 Jahre TNC

Impressionen zum Jubiläumstag «25 Jahre TNC»

30 Jahre TNC

Energie Zukunfts-Werkstatt am 10. November 2015