Frequently asked questions about wind energy in Southern Oregon.
We’re happy to answer your questions about wind energy systems. If you need more information, please call us at 541-897-0650.
Most wind machine manufacturers recommend an average annual wind speed of 12 mph. Some wind machines optimized for lower wind speeds may perform well enough to justify installation in areas with an annual average wind speed as low as 10 mph. Most sites in the Rogue Valley show an average annual wind speed of less than 10 mph. This doesn’t mean a wind turbine won’t work locally. It does means the amount of power produced may not justify the cost of installation.
Small machines that utilize a short, guyed tower can be installed for $3000-5000 per kilowatt. Larger machines mounted on taller towers are in the range of $10,000-12,000 per kilowatt. The quality of wind machines can vary greatly among different manufacturers. While cost is an important factor with any investment, the lowest price may not be the best criteria when choosing a wind turbine.
Many local residents feel the Rogue Valley is a very windy place. The historical wind data for Jackson County, however, does not show this to be the case. The only precise way to judge the wind resource at a particular site is by using a data monitor designed for wind assessment. The monitoring period is one year. This data can then be compared to nearby sites that have historical wind data, allowing an accurate prediction of the wind resource at the site.
A wind machine should be at least five rotor diameters above any obstruction within 300 feet (trees, buildings, hills) that can produce turbulence. Choosing the right turbine for a site requires balancing the cost of the installation against the value of the power that will be produced. Before you decide to install a turbine, be certain you know the full cost of the installation and the expected annual power production of the installation.
Both types of turbines have advantages and disadvantages. The vertical axis turbine is always facing the wind, so it doesn’t need a tail vane to align it with the wind—thereby simplifying construction. During rotation, however, half the rotor is forced to travel upwind, where drag steals performance. Also, most vertical axis wind machines have very short towers. The stronger the wind the better, and taller towers place a propeller wind machine into the most productive wind environment.