Montana Earth Science Picture of the Week

This map shows the best places in Montana to locate wind generators. Montana is located in the wind belt known as “the westerlies,” so winds generally blow from west to east across the state. However, wind speeds and frequencies vary greatly throughout the state due to variations in the shape of the land. For instance, mountains interrupt the westerly flow, funneling the air through passes and down valleys.

On the map, those areas that are purple, red, or blue have the best potential for generating electricity. The blue areas are considered to have the best (superb) potential, the red areas have “outstanding” potential, and the purple areas are considered to be “excellent” locations. The larger, red area in northwestern Montana marks the Rocky Mountain Front where the mountains abruptly end, giving way to the plains. Air spilling over the mountains accelerates down onto the plains, making the Front an “outstanding” area for the placement of wind generators.

According to experts, Montana ranks fifth among states for wind power potential. So, as a result of electricity shortages in recent years, power companies have started taking steps to develop Montana’s wind resources. Most of Montana’s electricity comes from two sources. The biggest portion is generated at coal-fired plants such as those located in Colstrip. Another source is hydropower, which originates at dams throughout the Northwest. Perhaps the biggest benefit that wind-generated electricity has over coal-generated electricity is that wind-generators do not produce any emissions. This is important because most scientists think that carbon dioxide from the burning of coal is contributing to global warming. On the other hand, some argue that large numbers of wind generators would damage the natural beauty of Montana landscapes.

How do we “generate” electricity? . . .
Basically you need three things: a magnet, a wire, and motion. If you were to take a magnet and move it in close proximity to a wire, you would cause an electrical current to flow within the wire. Within a generator, wires and magnets are organized so that a current will be produced in the wires if motion is provided. Generators can be designed to utilize all sorts of motion ranging from the peddling motion of a bicycle to the motion of water through the bottom of a dam. At coal-fired plants, coal is burned to heat water. As the water changes to steam it shoots through a turbine, providing the motion. With wind generators, the wind turns propeller-shaped turbines to generate electricity.

Right: Photo by David Grubbs, courtesy of the Billings Gazette . . .
This photo shows a man standing on one of the new wind turbines recently erected in central Montana (near Judith Gap). To learn more about this wind energy project, click on the Hot Link below. The article includes access to more cool photos taken by Larry Mayer and David Grubbs.

Term: generator