Windstalker – another way to harness wind
Windstalker is an alternative energy concept designed by Atelier DNA that recently took second place in the Land Art Generator competition. Like wind turbines, the Windstalker installation harnesses wind to produce power, however it does so using a very different method. Essentially it consists of extremely tall and thin structures that sway in the wind, and this kinetic movement can be harnessed to produce the electricity.
In this particular design, there are 1203 of these stalks spaced very close to one another, giving the appearance of a field of wheat swaying in the wind (albeit on a much larger scale!). Each of the stalks is 55 metres in height, and despite being 0.3m diameter at the base taper to only 5cm at the top. The stalks themselves are made up of carbon fibre reinforced resin poles making them extremely strong and are anchored to the ground with concrete bases approximately 10 to 20m in diameter, which define the spacing achievable from one stalk to the next.
How does Windstalker generate electricity?
The electricity itself is produced using piezoelectric ceramic disks, which are stacked upon one another within the stalk, with electodes sitting between them. Piezoelctric substances produce an electric charge in response to applied mechanical stress, so when the wind hits the Windstalker stalks, it causes compression of the disks generating a electrical current through the electrodes, which travels down to a torque generator located in the base of the stalks which produces the electricity that can then be used by consumers.
Like Wind Turbines, the wind stalks will only produce electricity when the wind is blowing and the stalks are moving, therefore electricity production is not constant. In an effort to compensate for this, beneath the Windstalker installation lies an energy storage mechanism that consists of two very large chambers which sit one upon the other. When the wind is blowing and electricity is being produced, some of this power is used to drive water pumps which pump water from the bottom chamber into the upper chamber. When the wind stops blowing, the water is allowed to flow through the pump in the opposite direction, from the upper chamber into the lower chamber, driving the turbine in the pump which connected to a generator can produce electricity, ensuring a more constant source of power.
Windstalker and current commercial proposition
The Windstalker project currently is purely conceptual, but based on technologies currently available to the scientific community. The estimated power output from an individual stalk is considerably less than a current wind turbine; however the stalks can be positioned much closer to one another, so the actual output per area unit is comparable. In addition this technology would have the benefit of lower noise pollution, less danger to wildlife (wind turbines are a real threat to birdlife), while still producing renewable energy with zero emissions. It will be interesting to see in the coming years whether the Windstalker energy concept is bought to life, and whether it will one day sit side by side with existing proven green technologies.