A phone call with consequences

Wind energy for Europe‘s buildings

How the Swiss start-up company Anerdgy became a partner in the prestigious Horizon 2020 project ZERO PLUS and how it contributes to shaping the designs of a new generation of net zero energy settlements. 

One spring day in 2015 Sven Koehler, CEO of Anerdgy AG received a call on his mobile phone. “Hello Mr. Koehler”, said the voice on the line. “We found your technology on the internet. There is this Horizon 2020 ZERO PLUS project. Would you like to join us?” The man on the line was Thomas Bock, professor at the Chair of Building Realisation and Robotics at Technical University of Munich, one of the leading partners involved in ZERO PLUS.

«I was attracted by their WindRail system,
a very innovative, advanced technology.»

A year later, in spring 2016, Sven Koehler is sitting alongside 25 academics, engineers, technology providers and building owners at the large table in the meeting room of the ABB convention centre near Bergamo, Italy. The ZERO PLUS consortium has come together for its first progress meeting, hosted by ABB Italy, one of the 15 partners participating in the project.

Six months have passed since the kick-off meeting in October 2015 in Cyprus. Now the heads of 10 “work packages” are to present their results. The bulk of the work during the past months has been basic research – collecting and linking data on standards, energy saving and production technologies, systems design, management and costs, as well as microclimate data of the places where the four case study settlements are to be built. A huge number of results and conclusions are presented and discussed in the course of the afternoon. But they are still on a rather academic level. The challenge for the consortium is to use this data for developing smart combinations of existing and new technologies and in concepts for managing buildings efficiently. Through four case study settlements the ZERO PLUS consortium has to prove that the project objectives can be achieved in the real world of settlement constructions.

In the next phase of the project, technology providers therefore play a crucial role. Based on the data and specifications of their colleagues from academia, they have to develop highly efficient, smart sets of technologies and concepts to build settlements which both produce even more energy than they consume and can be constructed at a much lower cost than today.

Small but crucial

This is where Sven Koehler comes in. His start-up Anerdgy is the smallest of the four technology providers taking part in the project, but is expected to play a key role. “Anerdgy was recommended by Shabtai Isaac from the Ben Gurion University of the Negev, when we were looking for a technology provider that can produce clean energy at the community level”, explains Matt Santamouris, professor of physics at the National and Kapodistrian University of Athens, and coordinator of the ZERO PLUS project. So why did Shabtai Isaac recommend Anerdgy? The professor of structural engineering answers with a smile: “Our partner at TU Munich found Anerdgy on the internet and asked me to screen it, before they would definitely invite Sven Koehler to join in. 

«This is quite a challenge
for a small start-up like Anerdgy,
technically and financially»

I was very attracted by his WindRail system – a very innovative, advanced technology, but not yet on the market. I contacted  Sven Koehler on Skype and was very impressed by his scientific expertise, his commitment  and his understanding of management. He fitted perfectly into the project.” So that was how the small Swiss start-up Anerdgy was invited to join the prestigious Horizon 2020 ZERO PLUS project in spring 2016. But what has Anerdgy to offer? Koehler names two fields where it can make a substantial contribution: “On the one hand there is our
WindRail technology, which we can bring into the case study settlements. On the other hand there is our knowledge in designing building technologies and in adapting our system to existing building technologies and products. In both these fields we have considerable experience and competence.”

Challenges for a small start-up

After the first day of the meeting Sven Koehler feels uneasy. The time schedule is very tight. The plans of the four case study settlements should be completed by the end of 2017 in order to start construction in 2018. But the exact shape of the houses, the technologies to be used and the integration of the WindRail system are not yet sufficiently defined. So on the second day of the meeting Sven Koehler decides to concentrate on talks with the case study owners and the technology providers. “This morning I will see Paolo Perani from ABB to align the electronics between WindRail and ABB. They are providing the inverter, we are providing the generator to produce electricity from wind and sun; and this has to be matched. And next I will meet Seongki Lee from TU Munich. He is responsible for the prefabricated façade design in which the house technology including our WindRail technology will be integrated”, explains Sven Koehler as we drive from the hotel to the ABB convention centre. 

Later in the day he meets the owners of the case study settlements from England, Cyprus, France and Italy one by one, in order to clarify the status of their building projects. 

«Our challenge is to provide
an optimum product that fits
the needs of all four case study

Some have changed shape in the meantime and have turned from large buildings with flat roofs to family houses with saddle roofs. This represents a fundamental change for Anerdgy, as its WindRail technology is basically designed for large flat-roofed buildings. So Sven Koehler and his team must now develop adapted WindRail versions. This is quite a challenge, technically and financially, for a small start-up like Anerdgy. “Definitely not an easy task,” Koehler admits. “Our challenge is to provide an optimum product that fits the needs of all four case study settlements.”

So, when the ZERO PLUS progress meetings end after three days, Sven Koehler takes home a bundle of problems to solve. “We now have to focus on some R&D aspects to provide the project with the right tools, on time,” he says on his way back from Bergamo to Zurich.  ‘On time’ means that the tools should be feasible within six months, for the next progress meeting in autumn. Nevertheless, Sven Koehler is confident of being able to meet these challenges. 

«We benefit from having
pilot projects all over Europe.»

And his start-up Anerdgy is already benefiting from participation in the Horizon 2020 ZERO PLUS project: “First of all we profit from having pilot projects all around Europe – this brings our knowledge to all the partners, and we also benefit from their knowledge. Furthermore we gain a deep understanding of the needs and behaviour of the stakeholders in such a complex project. And lastly, as this project is highly visible and well-communicated, it generates a strong marketing impact. It will demonstrate that our product is feasible for the whole European market,” concludes Koehler. So for Sven Koehler and his start-up Anerdgy, that phone call from Munich in spring 2015 was quite a lucky punch.

Anerdgy AG

Anerdgy AG is a Swiss start-up company in the energy and green-tech sector. It aims to bring renewable energy production close to the point of consumption by harvesting wind and solar energy on the roof edges of buildings. The company, based in Zurich, was founded in 2012 by Sven Koehler and became operational in 2013. Currently the Anerdgy team consists of seven employees.


is an innovative electricity generating system which is sited on the roof edges of residential, commercial and industrial buildings. It exploits three natural energy sources: solar radiation, wind, and pressure differences. The horizontal pinwheel powers the generator which produces electricity. The solar panels on the top of the module also generate electricity. In addition, the WindRail module can serve as a carrier for several building technologies such as lightning protection or rails for façade cleaning lifts. 

The WindRail technology was invented by Sven Koehler and developed by his Anerdgy team. At the moment Anerdgy offers two types of modules: WindRail C40 for large industrial buildings, and WindRail C30 for smaller commercial and residential houses. WindRail is expected to cover 20% to 50% of the electricity consumption of a large building. In May 2016 the first pilot project of a residential settlement using WindRail technology is being inaugurated in Berlin.

Interview with Sven Koehler
Sven Koehler

Sven Koehler graduated in Systems Engineering from the Erfurt University of Applied Sciences and obtained an MBA in General Management at the University of St. Gallen. From 2003 to 2013 he held several positions at Alstom Power and the Alstom Group in Switzerland and abroad. Since 2013 Sven Koehler has been CEO of Anerdgy.

Paolo Perani from ABB (right) explains the systems for Net Zero Energy (NZE) settlements to Philippe Moseley, project officer at the Executive Agency for Small and Medium-sized Enterprises (EASME) of the European Commission (middle).

HORIZON 2020 – ZERO-PLUS stands for one of the most ambitious R&D projects the EU commission has launched within the Horizon 2020 programme.  The project’s full official name “Achieving Near Zero and Positive Energy Settlements in Europe using Advanced Energy Technology” indicates its challenging objectives. By 2018 an international consortium of academics, technology providers and case study owners are to develop comprehensive, cost-effective systems for Net Zero Energy (NZE) settlements and implement them in four case studies across Europe. ZERO PLUS buildings have to meet three clearly defined specifications: a) to reduce the operational energy usage in residential buildings to an average 20kWh per m2 per year, b) to produce at least 50 kWh/m2 renewable energy per year, and c) to reduce the construction costs of zero plus settlements by at least 16% compared to current zero plus building costs.

To achieve these objectives, the consortium focuses on a series of strategies. Energy consumption will be reduced by a number of existing technologies such as efficient insulation, heating and lighting, as well as automated building energy management. To produce renewable energy, advanced photovoltaic systems and the innovative WindRail technology developed by the Swiss start-up Anerdgy will be integrated into the buildings. Further improvements will be effected by efficient management of loads and resources at a settlement instead of at a single house level. But the key point will be combining the various technologies and management tools into smart modules that can be customized and optimized to meet the specific requirements of each building, and implemented by cost-effective industrial processes. The schedule is as challenging as the objectives: by 2018 the four case study settlements should be up and running and prove the concepts are working. The results will then be monitored and disseminated for a market uptake. 

The ZERO PLUS consortium

consists of 7 universities and research institutes from Greece, Cyprus, Germany, Israel, Italy, and UK, 4 technology providers (among them ABB Italy and Anerdgy Switzerland) as well as 4 real estate companies from Cyprus, France, Italy and UK as case study providers. ZERO PLUS started in October 2015 and will end in October 2019. The project has an overall budget of 4.2 million euros and is coordinated by Matt Santamouris from the National and Kapodistrian University of Athens (UOA).