Thursday, July 3, 2008

Wind Power

As an engineer, I have never thought of most "alternative energy" schemes as much more than curiosities suitable for the better-off to install in their back yards as conversation pieces. Here's some confirmation on the wind power front.

It seems that not only is wind power unreliable, it's unreliable on a nation wide, and sometimes trans-national basis. Also, those gigantic wind turbines require some base of input power to keep the innards in working order whether they're running or not, so when a large high-pressure feature moves across your wind farm, not only is the whole system becalmed, it becomes a net user of power from other sources. On top of that, the mega-watts you thought the wind would provide now need to be provided by some other means, so wind power only makes sense if you have the conventional generating capacity to replace it when it stops producing.

Texas has a large wind farm located in west Texas, and spliced into the state grid. I remember, not long ago, that there were brownouts in Texas when the west Texas wind stopped blowing for a couple of days. When someone proposes putting in a wind farm, be sure and ask if the proposed price includes a coal-fired plant of the same capacity to take over when the wind drops.

There's a fellow with a ranch, located along I-25 south of Castle Rock, who has a windmill on his property. When the wind blows, he probably powers his spread, and even has some power left over to sell to Excell Energy, which they are required to buy at retail rates, which the government has mandated. It works because he's on the grid, and has a 100% backup should his system fail. I have to wonder, though, how long it will take to pay off the investment in the system.


Brad K. said...

I drove by that place while I worked in Colorado, about 1992. That windmill seemed to me to be more the Mother Earth News type of thing. What Sharon Astyk writes about on Casubon's Book - Peak Oil. The demise of utility electricity as the price to users escalates and denies service to the lowest income 2/3rds of the population. This guy in Colo. wants to have a potential source of occasional power, if (and when) the grid fails him.

There are people planning to live post-grid-failure. Some expect to revert to non-electric existence, others to partial service. Denver can certainly train a lot of Coloradans about living with brownouts and other partial-service training events.

In the 16 years the guy south of Castle Rock has been using his windmill, I imagine he has likely already paid for it - it went up at a time that there was no boutique market artificially boosting prices. Also no slick makers making windmills for government-subsidized big money projects.

And the wind blows fairly consistently, along the Front Range mountains there.

KD5NRH said...

You've also got to consider usage; it's not really all that hard for someone who goes to bed early, doesn't watch much TV, etc. to keep overall usage down to what a turbine and a few solar panels can provide.

Tom Gray said...

Actually, there are quite a few engineers (and more every day) working in the "alternative energy" field--so much so that portions of it, like wind, are becoming mainstream.

Engineers who would really like to know more about the details should consult the Utility Wind Integration Group (UWIG) site. Click on "Operating Impacts Study" to learn more about how wind power is being successfully integrated with utility systems across the U.S. today.

Utilities are not buying wind, or crediting it, as a firm capacity resource (one that can be counted on to meet peak power demand). That being the case, there is no need to back it up--it is backed up by the overall system reserves that back up all generating plants. (The size of the reserves, by the way, is determined not by wind, but by the size of the single largest conventional plant--usually coal or nuclear--so that when that plant suffers an unexpected outage, other resources can take up the slack.)

Thomas O. Gray
American Wind Energy Association