Q: What are the types of axis wind turbines available in the commercial market?
A. Currently vertical axis wind turbines are available in three primary designs: Darrieus model, giromill model, and savonius model. Of these, the Darrieus wind turbine, also known as ‘eggbeater’ turbine, owing to its unique design, was invented by George Darrieus in 1931. It is a low torque, high speed machine, which has proven highly efficient for electricity generation. This type of vertical axis wind turbine usually requires a push from an external power source to start rotating. Darrieus wind turbines have two vertically oriented blades that revolve around a shaft.
A Savonious wind turbine on the other hand is a high torque and low rotating machine. Its design is a lot similar to an anemometer. Savonious wind turbines use lift produced by airfoil-shaped blades in order to drive a rotor. Thus the speed at which Savonius vertical wind turbines rotate is slower than the approaching wind.
Q: What are the factors propelling the global vertical axis wind turbine market?
A. Unlike a horizontal wind turbine, orientation mechanisms to generate electricity are not required in a vertical axis wind turbine. This helps in substantially reducing the cost incurred on manufacturing the turbine. Furthermore, the repair and maintenance of vertical axis wind turbines are relatively easier and more convenient since major power generating components such as generator and gearbox are located toward the base of the turbine.
Besides this, vertical axis wind turbines claim to require lesser wind for generating an equivalent volume of energy, and can therefore be placed in lower altitudes where the velocity of wind is generally lower. The increasing awareness regarding the aforementioned benefits offered by vertical axis wind turbines is the primary factor fuelling demand from the market.
The market is also looking for numerous prospects of deploying vertical axis wind turbines in small-scale decentralized applications. These wind turbines are advocated as being capable of harnessing energy from wind blowing from all directions.
Q: How is the market gaining from the recent pilots and developments?
A: Iceland boasts exceptional potential of deriving power from wind energy. Renewable sources provide 100 percent of the electricity produced in the island nation. Despite being at the fore of generating power from renewable sources, the nation has been facing difficulties in harnessing wind power for use in residential applications. However with the launch of vertical axis wind turbines by Helix Wind, Iceland is looking to benefit from a promising design that may change the way in which the residential sector harnesses energy from the wind.
The Helix Wind Savonious 2.0 has the perfect design to be roof-mounted just 2 feet above the roof line or tower-mounted between 14 and 35 feet. Since the rotor of this vertical axis wind turbine spins in any wind direction, it is considered ideal for urban settings.
In another pilot, John Dabiri, a professor of bioengineering and aeronautical at Caltech, has revealed the possibility of reducing cost incurred on harnessing wind energy using vertical axis wind turbine models. A remote Alaskan village called Igiugig will be the first to demonstrate this new approach to boost wind power output.
With such R&D development activities underway, the future of the global vertical axis wind turbine market seems promising.