Wind Technology

The pages described below discuss the hardware and maintenance of today’s wind turbines, and how they can be incorporated usefully into the home, farm or business. Access the pages via the green links on the left.

Wind Energy Systems
This section defines some of the terms used to describe wind energy systems.

Traditionally, wind turbine designs have been dictated by their function. Probably the most familiar wind turbine is the “Dutch windmill,” a design developed centuries ago and used in Europe for grinding grain and pumping water. In the United States, the fan-type “water-pumper” can still be seen throughout the countryside, especially at remote watering wells in the western and plains states. Today’s modern wind turbines generate electricity using slender aerodynamic blades and tall towers. Because electricity is an indispensable part of life to most people, wind turbines are often interconnected with utility lines, so that power is always available on demand. However, a wind turbine can also be a valuable part of an energy supply system independent from the utility grid.

Wind and Wind Power
This section describes the characteristics of wind flow and explains how to measure and evaluate wind at a prospective wind turbine site.

Like the weather in general, the wind can be unpredictable. It varies from place to place, and from moment to moment. Because it is invisible it is not easily measured without special instruments. Wind velocity is affected by the trees, buildings, hills and valleys around us. Wind is a diffuse energy source that cannot be contained or stored for use elsewhere or at another time. It challenges us to harness it, but it first demands considerable study.

To be economically practical, a wind turbine should experience year-round average wind speeds of at least 12 mph. Sometimes people say, “The wind always blows at my place,” or “I live on the highest hill in the county.” These observations, while they may be true, are too simplistic. A careful wind survey should be made before buying a wind system. Wind turbine owners who buy without careful consideration are frequently disappointed in their system’s performance. At the going price for a complete wind turbine installation, it makes economic sense to first thoroughly check out your wind resource.

Wind Data
This section displays wind data from Iowa cities and towns in tabular and map formats, and includes conversion tables.

This 6-year project is collecting wind data from across the state and developing maps of the average monthly and annual wind speeds across Iowa using a GIS-based computer modeling technique. Detailed wind resource data is available for 2,346 individual locations in the state. Iowa Wind Resource Assessment has been rated as the most comprehensive public wind data collection project in the United States by the National Renewable Energy Laboratory (NREL).