Monday, December 28, 2009

Wind Turbines

On our way to San Francisco my husband and I were having a discussion about getting some wedding accessories for my grandparents 50th wedding anniversary next month, and all in a sudden we passed these wind turbines that caught my attention. It is pretty amazing! There are tons of them. This place is located at Altamount Pass, Livermore, California, USA. It is about one hour drive south east of San Francisco, right on the hills off the sides of highway 580. It is a splendid place, but kinda eerie. What is wind turbine by the way?
According to wikipedia, wind turbine is a rotating machine which converts the kinetic energy of wind into mechanical energy. If the mechanical energy is used directly by machinery, such as a pump or grinding stones, the machine is usually called a windmill. If the mechanical energy is instead converted to electricity, the machine is called a wind generator, wind turbine, wind power unit (WPU), wind energy converter (WEC), or aerogenerator.

The turbines form lines scattered on the hilltops, scattered around an area of about 15 kilometers in diameter. Hundreds are visible from the highway. The wind farm is composed of over 4900 relatively small wind turbines of various types, making it at one time the largest farm in the world in terms of capacity. Altamont Pass is still the largest concentration of wind turbines in the world, with a capacity of 576 megawatts (MW), producing about 125 MW on average and 1.1 terawatt-hours (TWh) yearly.

The small turbines are dangerous to various raptors that hunt California Ground Squirrels in the area. 1300 raptors are killed annually. Among them are 70 golden eagles that are federally protected. In total, 4700 birds are killed annually.