Precision is called for
In September 2013 the conceptual planning for the project begins. Before the frame can be produced, an elaborate 3D model must be realised. It will be tested by the client with the laser measuring device – because in the setup all rotors must be positioned exactly vertically in order to catch the wind optimally.
‘Pinpointed welding required a great deal of care,’ says Stefan Gönczi, the technician in charge from Tecpoles. In addition the Wind Tree did not involve a frame made out of a single piece. Around 60 individual parts, from the tree trunk to three main branches and a total of seven levels of branching small parts, had to be precisely adapted and coordinated with each other. ‘It was like an oversized puzzle made from steel,’ recalls Gönczi. Every single tube was labelled with a welded letter on the inside on each end before being coated white. ‘After coating at above 450 °C any other lettering would have disappeared,’ explains the head of the technical team.
A tree grows in two days
A further challenge is the transport of the large quantity of specially-bent single parts to France. In March 2014 Stefan Gönczi and another technician from Tecpoles accompany the cargo to the French community of Pleumeur Bodou. With the help of the French colleagues, the tree is erected in the Parc du Radôme theme park.
First the tree trunk frame is wired and the ‘leaves’ – the green electricity-producing micro-turbines – are mounted on the steel branches and twigs. With the help of an aerial work platform, the single parts are then mounted on the appropriate branches by means of flange connections. After two days the tree is ready to start producing energy.