{"id":648,"date":"2012-12-03T14:43:17","date_gmt":"2012-12-03T18:43:17","guid":{"rendered":"http:\/\/blogs.bu.edu\/ek130wind\/?p=648"},"modified":"2012-12-03T16:01:17","modified_gmt":"2012-12-03T20:01:17","slug":"how-many-birds-to-turbines-really-kill","status":"publish","type":"post","link":"https:\/\/blogs.bu.edu\/ek130wind\/2012\/12\/03\/how-many-birds-to-turbines-really-kill\/","title":{"rendered":"How Many Birds Do Turbines Really Kill?"},"content":{"rendered":"

Hate Windows, Not Wind Turbines<\/strong><\/p>\n

Windows kill over one hundred million birds each year in the United States alone, that\u2019s over ninety nine million nine hundred and eighty thousand more than wind turbines, yet you don\u2019t see people protesting the use of windows.1<\/sup><\/p>\n

In fact, a study conducted by the AWEA in 2006 concluded that less than \u201c0.003% (3 of every 100,000) of bird deaths caused by humans and pets\u201d is caused by wind power.2<\/sup> A study published in Renewable Energy: An International Journal <\/em>states that \u201cwind farms . . . are responsible for between 0.3 and 0.4 fatalities per gigawatt-hour (GWh) of electricity while fossil fueled power stations are responsible for about 5.2 fatalities per GWh.\u201d1<\/sup><\/p>\n

<\/p>\n

Figure 1 below shows that wind energy is not even competing with the leading causes of bird deaths. \u00a0Topping the chart is feral cats, followed closely by windows.<\/p>\n

\"\"<\/a>

Figure 1: Number of birds killed by various causes<\/p><\/div>\n

Birds aren\u2019t the only flying critters being affected by the furious spinning weaponry known as wind turbines.\u00a0 Bats are having a similar issue with avoiding the deathly blades.\u00a0 But its not just running into the blades that kills bats.\u00a0 The main issue for this mammal is lung explosion:\u00a0 \u201cbats die in the blade vortices.\u00a0 Rotating turbine blades create negative pressure pockets, and when the bats fly through them, their lungs explode.\u201d3<\/sup> This kills hundreds of thousands of bats per year.\u00a0 So even though turbines have virtually no effect on birds they do have a major effect on the bat community.\u00a0 It is estimated that in one fall migration a single wind farm can kill hundreds of thousands of bats.3<\/sup><\/p>\n

Engineers and scientists have found that there is a simple fix to save the lives of 93% of possible bat fatalities.\u00a0 Merely increase the cut-in speed of turbines from their usual 8 or 9 miles per hour (mph) to 11 mph.\u00a0 They also concluded that this increase in cut-in speed would result in less than one percent power loss.3<\/sup> This makes sense.<\/p>\n

Let us use New York, a place where thousands of bats are killed by wind turbines, to go over a few scenarios.\u00a0 In New York the average wind speed around a wind farm is about 7 meters per second (mps), 15.6 mph.\u00a0 Now if we the wind speed will be above 11 mph 84 percent of the time, and above 9 mph about 91 percent of the time.\u00a0 The power curve below for the GE 2.5-103 shows that this typical wind turbine has a cut-in speed of 6.7 mph.\u00a0 The power generated at that speed is very minimal.\u00a0 At 11 mph (about 5 mps) the power generation is still relatively low.<\/p>\n

At 15.6 mph (about 7 mps) the power production is significantly greater, around 1200 kW.\u00a0 Now we look at the area under the curve from the cut in to 11 mph which is about 602688 kWh. The work at the average wind speed is 10.5 million kWh.\u00a0 This shows a 9% loss in work production which is greater than the claim of 1 percent but still relatively low.\u00a0 So, we can save the lives of tens of thousands of birds and bats by only sacrificing less than 9% of the power generation.<\/p>\n

\"\"<\/a>

Figure 2(4) Power Curve for the 2.5-103 Wind Turbine<\/p><\/div>\n

 <\/p>\n

All in all, there should not be a soul on earth that thinks wind turbines kill too many birds, especially with the simple fix that is most likely being put into place. \u00a0At least in New York where the study was done.<\/p>\n

 <\/p>\n

 <\/p>\n

Work Cited<\/strong><\/p>\n

1<\/sup>The Avian Benefits of Wind Energy: \u00a0A 2009 Update, Renewable Energy: An International Journal<\/a><\/p>\n

2<\/sup>American Wind Energy Association:\u00a0 Energy and Wildlife<\/a><\/p>\n

3<\/sup>Increasing Wind Turbine Turn-On Speeds Could Help Reduce Bat Deaths, Popular Science<\/em><\/a><\/p>\n

4<\/sup>GE Power Curve<\/a><\/p>\n

Wind Energy Market<\/a><\/p>\n

Federal Policy<\/a><\/p>\n

Wind Speed<\/a><\/p>\n

Wind Energy Development Environmental Concerns<\/a><\/p>\n

<\/a><\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

Hate Windows, Not Wind Turbines Windows kill over one hundred million birds each year in the United States alone, that\u2019s over ninety nine million nine hundred and eighty thousand more than wind turbines, yet you don\u2019t see people protesting the use of windows.1 In fact, a study conducted by the AWEA in 2006 concluded that […]<\/p>\n","protected":false},"author":3364,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[26959],"tags":[],"_links":{"self":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts\/648"}],"collection":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/users\/3364"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/comments?post=648"}],"version-history":[{"count":6,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts\/648\/revisions"}],"predecessor-version":[{"id":698,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts\/648\/revisions\/698"}],"wp:attachment":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/media?parent=648"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/categories?post=648"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/tags?post=648"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}