|
|
|
May 19, 2009
Power From Wind
I think it might be a good idea to look at how a wind generator's output varies with speed. Wind power varies with the cube of wind speed. That is basic physics. No way around it that we know of. So let us look at some wind turbines. Typical are turbines that start generating power at wind speeds of 2.5 meters per second and max out at wind speeds of 16 meters per second or 20 meters per second. First let us convert that to miles per hour to get a feel for the speeds involved. 2.5 m/s = 6 mph Now let us look at output. If you consider 2.5 m/s minimum output then at 16 m/s maximum output the max/min ratio is 262. At 20 m/s the max/min ratio is 512. Or consider a wind blowing at 90% of maximum turbine rating. Output is 73% of maximum. At 80% output is 51% max. At 70% it is 35%. At 60% it is 22%. At 50% it is 12.5%. At 40% you are down to 6.4%. At 30% you are down to 2.3%. At 20% you are at less that 1%. Economically it is probably useless (other than to impress the rubes) to design wind turbines that can handle max/min ratios more than 5 or 6 to 1. And from a practical stand point useful effectiveness is actually in the 2 to 1 range. So it is not just having wind. You really need a very stiff breeze to generate useful power. I think our experiment with deploying massive amounts of high cost wind power are just about over. If the costs come down that improves the situation some. But not a lot. Evidently Mr. Obama and his Green friends have never run the numbers. Inspired by Glasgow Looking To Freeze In The Dark Cross Posted at Power and Control posted by Simon on 05.19.09 at 04:43 PM
Comments
dr. kill, What is that about? Did we win some kind of award I am unaware of? M. Simon · May 19, 2009 07:54 PM According to Wikipedia, typical capacity factors are 20-40% http://en.wikipedia.org/wiki/Wind_power#Capacity_factor By your numbers, 20% is about what you get at about 60+% of optimal windspeed. I bet you have to have an unusually good location to get up to 40%. I wonder how many of the best sites for wind stations have already been tapped. SteveBrooklineMA · May 19, 2009 11:15 PM Dr Kill's comment reminds me of a question I've had for a while... Who are you people? Seriously, I've been reading your blog for years, and have no idea. I don't even know if M. Simon is the same as Simon. I don't know anything about Eric either. Where are you? Do you have jobs? Mousetrap research? Retired? How about a short bio? SteveBrooklineMA · May 19, 2009 11:35 PM M. Simon and Simon are the same. Who are we? You can learn a lot by reading how we think. Way more interesting than a bio. Plus Eric and I prefer a little mystery. We do share a few secrets between each other at meet ups. But other wise it is not for public consumption. My main interest these days is: M. Simon · May 20, 2009 02:35 AM "Evidently Mr. Obama and his Green friends have never run the numbers." That would require the use of logic. You know, the kind that Harvard law grad and Gaia worshipers don't use as much. Blademonkey · May 20, 2009 02:39 AM The wind generators are designed to clutch out when the wind speed exceeds turbine rating. So too little wind = no power "Evidently Mr. Obama and his Green friends have never run the numbers." RFOL!!! metalman · May 21, 2009 12:48 AM |
|
June 2009
WORLD-WIDE CALENDAR
Search the Site
E-mail
Classics To Go
Archives
June 2009
May 2009 April 2009 March 2009 February 2009 January 2009 December 2008 November 2008 October 2008 September 2008 August 2008 July 2008 June 2008 May 2008 April 2008 March 2008 February 2008 January 2008 December 2007 November 2007 October 2007 September 2007 August 2007 July 2007 June 2007 May 2007 April 2007 March 2007 February 2007 January 2007 December 2006 November 2006 October 2006 September 2006 August 2006 July 2006 June 2006 May 2006 April 2006 March 2006 February 2006 January 2006 December 2005 November 2005 October 2005 September 2005 August 2005 July 2005 June 2005 May 2005 April 2005 March 2005 February 2005 January 2005 December 2004 November 2004 October 2004 September 2004 August 2004 July 2004 June 2004 May 2004 April 2004 March 2004 February 2004 January 2004 December 2003 November 2003 October 2003 September 2003 August 2003 July 2003 June 2003 May 2003 May 2002 AB 1634 MBAPBSAAGOP Skepticism See more archives here Old (Blogspot) archives
Recent Entries
• It's An Absolute Disgrace
• The Seeds Of Stupidity • Remember D-Day • Newton's Cradle • Taxes Send Jobs Offshore • The law is the law! • A teaching moment? • You Can't Do It At Random • In debt to Islam? For Western thought? • David Carradine Is Dead
Links
Site Credits
|
|
Congratulations to you for the success of your blog, and also to M. for his valuable contributions. Many more.