Gauntlett: Vertical axis wind turbines: back in the game, or more of the same?
By Dexter Gauntlett, Navigant Research
Vertical Axis Wind Turbines (VAWT) appear to be making a comeback after a few decades of dormancy, but it’s unclear how much legs the somewhat maligned technology will have in the market.
VAWTs are most commonly known in the US from their days in California during the 1970’s-early 1990’s when Sandia National Labs and several private companies worked together to design and deploy 500-600kW utility-scale VAWTs in California. The units worked fairly well, even if not as well as expected, for a number of years but ultimately ran into mechanical problems that stifled their commercial viability.
By that time, interest had largely shifted to today’s more common 3-bladed horizontal axis wind turbine (HAWT) designs and the HAWT industry has never looked back.
VAWTs do potentially offer advantages over HAWT including typically requiring less wind to function meaning they can be located closer together and closer to the ground for easier maintenance and installation. There are at least 28 active VAWT manufacturers in the world today primarily producing <10 kW units intended for use in urban and building-integrated settings.
However, many companies in this sector have faced significant financial challenges such as Helix Windpower and Windspire. Small wind turbines in general have faced increased scrutiny as there are many cases of both VAWTs and HAWTs not performing as stated in the urban environment.
The establishment of the Small Wind Certification Council has been a major step forward for a small wind industry that is looking to regain credibility. Only 5 small wind turbines are currently certified by the council, all HAWTs.
This did not prevent the largest building-integrated VAWT installation in the US coming online in June 2012, which utilized 18 4.5 kW Venger Wind V2 turbines on the roof of Oklahoma Medical Research Foundation. The V2 wind turbines are 18.5 ft tall and are designed to start producing electricity at 8.9 mph, well below Oklahoma City’s annual wind speed average, according to the company.
If you are commenting using a Facebook account, your profile information may be displayed with your comment depending on your privacy settings. By leaving the 'Post to Facebook' box selected, your comment will be published to your Facebook profile in addition to the space below.