Some days ago we celebrated the entry of TWE Tandem Wind Energy in the Danish Positive List, which is the list of wind turbines which are approved for sale in Denmark.
As the company has been around us for a while, it is now time to find out a bit more about it and about the person behind it.
Let’s start from the beginning: who are you?
My name is Otto Reinke, I am from Germany and I am the founder and managing director of TWE Tandem Wind Energy GmbH.
Wind energy was not always your focus, right?
That is correct. My background is in economics. In the past I have held senior management positions in international corporations, medium-sized family-owned companies and private equity backed start-ups, in different markets ranging from consumer electronics to renewable energy. A lot of my work has focused on setting up and expand international sales and service companies as well as finding and establishing distributors and sales partners in Europe and Middle East.
So, how did you end up with wind turbines?
Well, some friends of mine, knowing that I was working as international business developer, asked me to support them in preparing a business plan for small wind turbines. I decided to accept, but then they stepped down, so I continued the project by myself.
How did you end up in Nordic Folkecenter?
I was looking for a test field for testing the first version of our wind turbine and I talked to Tonny (Brink, our CTO and responsible for the test center, ed.) about the possibilities. There are not so many places in in Europe for testing small wind turbines: there was a place in Austria, but it was too far, one in the Netherlands, but they stopped their activities and the one of Nordic Folkecenter in Denmark. I decided for this because of for your very professional approach.
Tell us about your wind turbine. How was it looking like when you first come here and how is it now?
The wind turbine was based on a development made by SMA Solar Technology AG and this was the first version I tested in Nordic Folkecenter. At that time it was a downwind model, with a nominal power of 5 kW and protruded rotor blades. When I tested that model in Nordic Folkecenter, everyone was smiling and afterwards I found out why…
Why?
Well, despite the good work, there were quite some changes to be done.
To begin with, we decided to change the design from downwind to upwind (meaning: from getting the wind from the back, to getting the wind from the front, as most wind turbines do, ed.); we developed a new controller, a designed a new rotor and added a yaw system, for aligning the wind turbine to the wind optimally.
Blades were re-designed, followed the advice of Viggo Øhlenschlæger, a local engineer behind many of the buildings in Folkecenter. First we used wood, for rapid prototyping and, once the design was optimized, we turned into fiber glass.
Changing from downwind to upwind sounds is a major re-design: why did you decide to go that way?
Unfortunately, the downwind configuration was very noisy. We tested different techniques to get rid of the noise, but we could not manage it. Therefore, we decided to go upwind and to create a new rotor blade profile.
Any other changes?
Yes, because of the new technical configuration we created a new nacelle design (the housing where all the machinery is located, ed) . Finally we started preparing for certification. Everything was done in cooperation with Nordic Folkecenter, as a team.
Speaking about certification: what did you do?
We had to do blade tests, duration test, safety test, noise tests and prepare a large number of documents for the Type Certification ref. BEK 648 /1/ (Danish rules), for the reference standards IEC 61400-22 /2/ and IEC 61400-2 /3/. We had to document the quality process of the manufacturing process and provide, drawings, installation manuals, service manuals, construction manuals, etc. It was a long process, but we finally made it!
In parallel, we did the measurement for grid compliance for the German, Belgian, Dutch and Danish grid requirements. As today, we have a turbine which is a proven product, so we are ready to start now with the sales activities.
Who is your customer?
We are targeting private households, farmers, small commercial companies, customers in the rural electrification area, local communities and, in general, all applications involving decentralised energy supply.
How was to work during COVID?
It was challenging, because it was difficult to get components for modifying the turbine because the supply chains were interrupted. Additionally, it was very difficult to cross the border: I always needed a negative COVID test and a confirmation from Nordic Folkecenter saying that I had to go there for repairs or to change components.
What are the strong points of your turbine?
We are one of the few (or the only one) which is using a yawing system in this power range. We have integrated the components in a single-frame aluminum housing. The new controller is using standard components, making it easy to repair. Furthermore, the wind turbine can be taken up and down by using a winch, which makes service very easy and removes the need of having a “work at heights” certificate. The performances are quite good and the quality is certified by international standards. We also have the possibility to customize the turbine, based on the customer’s wishes, which means that we can put their logo on the nacelle. This can be an interesting marketing tool for companies showing their sustainability behaviour. And, last but not least, it has survived the very tough weather conditions in Nordic Folkecenter!
You have been with us since 2019. How would you evaluate the support you received from Nordic Folkecenter?
Great! It is a very experienced team, always ready to have very friendly and constructing discussions. During the whole development they have been very supportive. The availability of a workshop, compared to having just an open field, is great, as it makes it very convenient for changing components. Finally, Nordic Folkecenter has more than 40 years of experience from which I could benefit.
So, would you recommend it to other developers?
Yes, to everyone, disregarding their stage of development. Their knowledge and experience can adapt to most needs. Just do not forget to bring chocolate, to the discussions!
Anything else you would like to add?
Yes. We are now looking for distribution partners. So, if anyone is interested in this or can help us building an international distribution network we would love to hear from them.
Any requirement?
Well, we would like them to be already active in the small wind turbine and/or renewable energy market and interested in introducing our product in their country. They should basically represent us in that specific country and provide sales, service and consultancy to the customers. Of course, we will provide them with the necessary information and training.
Those who are interested can get in contact with us via our webpage (https://www.twe-tandem-wind-energy-gmbh.de) or mail (info@tandemwindenergy.de).
Thanks a lot Otto for testing together with us. We wish you best of luck with the sales of your turbine.
Videoes with Otto Reinke, TWE-Tandem Wind Energy GmbH
Below you can find the presentations Otto did during our past Small wind conferences. If you are interested in the topic, you should not miss this year’s edition, taking place on September 24th and 25th. More info and registration on http://www.folkecenterevents.net/