Reply #3: You've misunderstood the article - Pickens is getting a lot more than 8.7% [View All]

o 11:52 am August 6, 2009
o Michael Goggin, American Wind Energy Association wrote:

This article makes the common mistake of confusing capacity factor and capacity value. As the National Renewable Energy Laboratory study cited by the article explains, capacity factor is a measure of the amount of energy produced by a wind plant, while capacity value measures the amount of capacity a plant contributes towards meeting peak electric demand. 30-40% is the typical capacity factor of a wind plant, while 10-20% is the typical capacity value.

Wind plants are being built to provide large amounts of low-cost electricity to reduce the use of expensive fossil fuels and the pollution that results from their use. Folks in Texas can tell you that wind energy has already saved them billions of dollars by reducing the use of expensive natural gas and coal, while also reducing carbon dioxide emissions by millions of tons. Since reducing fossil fuel use and emissions are both issues of energy and not capacity, from that perspective the only metric that matters is the capacity factor of a wind plant. While a capacity factor of 35% may sound low to some, that is actually significantly higher than the capacity factors of other types of power plants. Natural gas plants typically have capacity factors of around 10%, hydroelectric plants are often around 25-30%. Even coal plants typically only have capacity factors that are in the 60-70% range.

For those who would like to delve a little deeper into the difference between energy and capacity, I would suggest this article:
http://www.awea.org/pubs/factsheets/Baseload_Factsheet.pdf