Monday, November 26, 2007

Pros and Cons of Wind Energy

Here is a link to another article in an ever increasing list of discussions about wind power and its pros and cons. More and more negative or problematic points about wind energy are surfacing, and it is mostly because wind energy is starting to have a measurable impact instead of just being 'in the noise' of the electricity generation mix.

Essentially, because utility and grid operators don't know exactly when wind power will be getting generated due to the unpredictability in wind speed, there are additional actions that need to be taken in operating a reliable electric grid. As the amount of installed wind capacity (the MegaWatts installed if all wind generators were operating at maximum power) gets to over 10% of the entire grid capacity (wind, nuclear, coal, natural gas, hydroelectric, etc.), the other electrical generators are required to operate to account for the increased wind capacity. This assumes, of course, that you are going to allow the full available wind power onto the grid at any given time.

A study by GE (see http://www.ercot.com/meetings/ros/keydocs/2007/1022/Variablity_and_Predictability_draft_dlvd_2a.zip, or link on page http://www.ercot.com/calendar/2007/10/20071022-ROSWIND.html), done for the Electric Reliability Council of Texas (ERCOT)
shows that the dispatchable generators (those that can be turned on at any time) have to be able to ramp up and down faster the more that wind is integrated into the grid. Interestingly, the predictability of the total load that needs to be served by the dispatchable generators stayed about the same as without wind. This is because there is already enough uncertainty in the electricity demand throughout the day such that the added uncertainty of wind generation was not incredibly influential.

Basically, with more wind, we are deciding how many other additional aspects (higher generation ramp rates, more transmission lines, etc.) we are willing to deal with to have a clean source of electricity. The fact that wind energy is getting questioned for its newly-perceived (though not new at all) drawbacks is a testament to the wind industry already solving many problems to become a mainstream source of electricity.

No comments: