The Wall Street Journal wrote a front page article titled “Natural Gas Tilts at Windmills in Power-Generation Feud“. This article was well written and describes a controversy in Texas related to wind energy and their (inherent) inability to deliver reliable power.
Texas is unique in that it is “walled off” from the rest of the USA on its own grid called ERCOT. To be technically correct, the Texas grid doesn’t include El Paso (I used to consult out at El Paso Electric) but that part of the state really is more like New Mexico, anyways.
Texas has a large percentage of wind power – 6% for 2009. The other sources of generation are about 20% for nuclear, 30% for coal, and 45% for natural gas. Per the article:
Texas… has 9,400 megawatts of wind-power generation capacity – more than all the power plants in Utah. Texas has more wind power than any other state… more than three times as much as California.
Power is generally dispatched in the following manner:
1) the grid control operator makes a request for how many megawatts of power that it needs for the next day
2) the various owners of generating capacity (wind, gas, coal and nuclear) submit their available power for the next day
3) the wind power is always taken because it has the lowest incremental cost, along with the nuclear power available as well as coal. Then natural gas is selected until demand is equal to supply, with older less-efficient “peak” gas plants turned off if there isn’t enough demand
The issue is that wind power can’t guarantee its available capacity. In general, if a generation owner “commits” to a certain amount of supply capacity and can’t provide the electricity, then that generation company is charged a penalty for failing to deliver.
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