How To Build A Wooden Wind Turbine From Scratch!
by Simon Goess
In this post I will share the experience I made during the small wind turbine construction course, which took place in Nea Makri near to Athens from the 19th to 28th of December 2014. As adding pictures and alike is rather difficult in wordpress, I made a PDF of the text with a better format, which you can download here.
The course was arranged by Nea Guinea, a not-for-profit organization that places the self-reliance of some of our basic everyday needs, such as food, energy, health, shelter and clothing as a central objective. By offering theoretical and practical workshops in the abovementioned themes, the people involved in Nea Guinea try to gather and to spread necessary knowledge and craftsmanship in order to get actively involved in production processes and reach higher levels of self-sufficiency and autonomy. In the same vein, Nea Guinea represents the process of shaping economically sustainable and socially just processes in opposition to the dominant economic system. In cooperation with similar projects it also aims at the creation of solidarity networks that enable the transition to a more just, ecological and sustainable society.
The course instructor Kostas Latoufis, co-founder of Nea Guinea, has been active in the off-grid renewable energy sector for 10 years now, after having completed his electrical and electronic engineering degree at the Imperial College of London. He started to construct small wind turbines in 2007 and by now has several years of experience in teaching hands-on renewable energy systems.
I met Kostas during the Degrowth Conference 2014 in Leipzig and remembered his presentation on off-grid and community renewable energy as quite intriguing. Therefore, I was very excited when he announced that there will be another workshop on how to build a small wind turbine in December 2014.
In total we were five participants with various backgrounds and at least speaking for myself with little skills in craftsmanship. Nevertheless, Kostas reassured us that we will be able to finish the construction of our small wind turbine within 9 days. The wind turbine we set out to build, is based on the design of Hugh Piggott, one of the pioneers of modern do-it-yourself small wind turbines, who lives off-grid on the Scoraig peninsula in North West Scotland.
The main components of the DIY wind turbine are the rotor, the alternator (an axial-flux generator), the tail and the mechanic frame that connect all of the other parts. The rotor of the wind turbine we built has a diameter of 2.4 meters, which means each of the three wooden blades has a length of 1.2 meters. The alternator, basically two magnet disks that rotate with the blades and the stator, which consists of the assembly of the coils, has a power rating of around 700 W, but the output varies according to the wind speed. Both the magnet disks and the assembly of coils had to casted in vinyl ester resin by using moulds. This is necessary to prevent corrosion of especially the magnets and to provide stability for the parts of the alternator. The task of the tail, which is a plywood vane bolted to flat steel bars on a steel pipe, is to turn the rotor into the wind direction (to yaw) in order to capture a maximum of the power and to allow the turbine to swing out of the wind in case of too high wind speeds (furling) to prevent damages.
All of the above might seem quite complicated and difficult to imagine, so in the following I will present a walkthrough of the construction of our wind turbine including photos to ease the understanding and to provide some feel for the construction work.
Obviously a variety of different tools had to be used during the construction process, which I will not be able to elaborate on here. Most of us did also not have much experience in handling them, but through superb explanations and supervision of our instructor Kostas, we were able to use the tools without bigger problems (with some exceptions, so be aware of the spoke shave).
The first day:
On Saturday morning we set out to have our first day at the workshop, which was located in the garden of a residential house near to the Mediterranean Sea. With around 15 degrees Celsius, a bright sun and blue sky we were eager to start building the blades of our wind turbine.
After some preparations and the explanations of the tools we started to turn the three wooden planks into the blades. The wooden planks had to be cut and carved in order to achieve the appropriate shape of the blades. All of the measurements for cutting and carving (as well as for all the other steps and parts of the wind turbine) are detailed in Hugh Piggot’s “A Wind Turbine Recipe Book”.
With 6 people at the workshop, two could work on one blade and try the different tools.
Below you can see our workshop, basking in sun and surrounded by lush Mediterranean vegetation. A perfect place to create a wind turbine, reminding us of a more natural and sustainable way of life.