ADVERTISEMENT
  About the SA Blog Network













Observations

Observations


Opinion, arguments & analyses from the editors of Scientific American
Observations HomeAboutContact

Wind Turbines Generate “Upside-Down” Lightning [Video]

The views expressed are those of the author and are not necessarily those of Scientific American.


Email   PrintPrint



image of lightning emanating off of several wind turbine bladesLightning strikes have been known to incapacitate wind turbines by destroying their blades. But while most tall structures are prone to lightning strikes, wind turbines seem to be especially susceptible. Recently scientists captured high-speed footage of these strikes, and they discovered that the wind turbines may in fact be the architects of their own demise: the nature of the turning turbine helps to cause these strikes.

Typically when lightning strikes a tall object, the strike is initiated from the cloud. A channel of negatively charged plasma, called a negative downward leader, moves from areas of negative charge in a storm cloud down toward a positively charged building, tree or wind turbine. As the negative leader nears the structure, it induces a positive upward leader, which jumps up to meet the negative leader. The connection forms a current, and the bright lightning flash we observe is actually to the result of a shock wave flowing up the connected channels, called a return stroke.

In the case of these wind turbines, positive upward leaders are generated from the turbine blades in the absence of a negative downward leader from the clouds above. These upward leaders are the zigzagging lines that grow up toward the sky in the beginning parts of the video (below).

In the paper describing their findings, published online February 6 in the Journal of Geophysical Research, the researchers describe the phenomenon they think is responsible for this lightning. When tall objects build up a positive charge underneath a negatively charged storm cloud, they form a cloud of positively charged ions, which helps to dissipate the electric field around them. But, says Oscar van der Velde, a researcher at the Polytechnic University of Catalonia and a co-author of the paper, “if your blade can escape this cloud of ions, then the field will remain high. And if the field is high enough, you can trigger a real lightning flash.”


In the video—which takes place over just 150 milliseconds—the lines that stay illuminated have formed currents with the clouds above. Still, there is no bright flash and thus no return stroke, van der Velde says: “If you get a return stroke… it saturates the image.” This is just as well for the turbines because the return stroke is the most damaging part of a lightning strike. Yet “even discharges without return strokes can cause progressive damage to the turbine materials, ultimately leading to their failure,” van der Velde points out.

Geoffrey Giller About the Author: Geoffrey Giller is an editorial intern at Scientific American. Follow on Twitter @GeoffreyGiller.

The views expressed are those of the author and are not necessarily those of Scientific American.





Rights & Permissions

Comments 19 Comments

Add Comment
  1. 1. jtdwyer 6:30 pm 03/3/2014

    Geoffry,
    There seems to be many commercially available wind turbine lightning surge protection systems on the market that include a lightning rod within each blade and claim to be effective – were these turbines so equipped?

    Link to this
  2. 2. SAULT18 6:38 pm 03/3/2014

    Just to head off the usual comments from the renewable energy haters around here, but this isn’t a widespred problem for the wind power industry. There are not hundreds or even dozens of turbines getting zapped by lightning and failing every year. Like the article says, these positive leaders lead to some wear-and-tear on the turbines, but wind turbine longevity data are actually pointing to longer operational lives for wind turbines than previously thought:

    http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_20-2-2014-9-18-49

    By lowering the damage than lightning does on wind turbines, they will eventually be able to generate power for even LONGER!

    Link to this
  3. 3. Agre1958 8:48 pm 03/3/2014

    $9­­­­­­­­­7­­­­­­­­­/­­­­­­­­­h­­­­­­­­­r­­­­­­­­­ ­­­­­­­­­p­­­­­­­­­av­­­­­­­­­iv­­­­­­­­­d­­­­­­­­­v­­­­­­­­­ b­­­­­­­­­y G­­­­­­­­­oog­­­­­­­­­le­­­­­­­­­, I­­­­­­­­­ am ­­­­­­­­­making ­­­­­­­­­a ­­­­­­­­­good ­­­­­­­­­salary ­­­­­­­­­from ­­­­­­­­­home ­­­­­­­­­$5500­­­­­­­­­-­­­­­­­­­$7000/week , which ­­­­­­­­­is ­­­­­­­­­amazing, ­­­­­­­­­under ­­­­­­­­­a ­­­­­­­­­year ­­­­­­­­­ago ­­­­­­­­­I ­­­­­­­­­was ­­­­­­­­­jobless ­­­­­­­­­in ­­­­­­­­­a ­­­­­­­­­horrible ­­­­­­­­­economy. ­­­­­­­­­I ­­­­­­­­­thank ­­­­­­­­­­­­­­­­­­God every ­­­­­­­­­day ­­­­­­­­­I ­­­­­­­­­was ­­­­­­­­­blessed ­­­­­­­­­with ­­­­­­­­­these ­­­­­­­­­instructions ­­­­­­­­­and ­­­­­­­­­now ­­­­­­­­­it’s ­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­my ­­­­­­­­­­­­­­­­­­duty ­­­­­­­­­to ­­­­­­­­­pay ­­­­­­­­­it ­­­­­­­­­forward ­­­­­­­­­and ­­­­­­­­­share ­­­­­­­­­it with ­­­­­­­­­Everyone, ­­­­­­­­­Here ­­­­­­­­­is ­­­­­­­­­I ­­­­­­­­­started…….http://x.co/40BGY

    Link to this
  4. 4. jtdwyer 12:04 am 03/4/2014

    SAULT18,
    I’m not a renewable energy hater, but I do question everything. I don’t understand what a report of U.K. wind generator longevity has to do with the risk of lightning damage to wind farms in Kansas, or Florida, for example…

    Link to this
  5. 5. Carlyle 3:04 am 03/4/2014

    SAULT18 BOO! :)

    Link to this
  6. 6. m 3:19 am 03/4/2014

    Let me get this right, turbines get hit with several MILLION VOLTS and we are not pumping that into the electricity grid…

    Does any one else see an anomaly here….the windmill spins for ages just to get the same amount of power it gets from one hit…

    Channel the damn lightning into the grid… you will then get a million times the electricity from a windmill.

    Link to this
  7. 7. hatemnajdi 4:57 am 03/4/2014

    m:
    Good point. But is the number of thunderstorms big enough to make investing in collecting electricity from them worthy? And are thunderstorms, their time and place of happening predictable to make the investment returns satisfactory?

    Link to this
  8. 8. phalaris 6:45 am 03/4/2014

    m :
    you can’t be serious – do you know the difference between voltage and power (watts)?
    Well, it’s a typical level of knowledge for a greenie.

    Link to this
  9. 9. phalaris 6:50 am 03/4/2014

    ..talking of the level of knowledge of greenies.. we have Sault here as well.
    The news you post is fantastic: it means we won’t screwed for subsidies any longer for wind, and the network operators won’t be forced to take its useless output when they don’t want it.

    Link to this
  10. 10. anumakonda.jagadeesh 7:16 am 03/4/2014

    A Statistical study is needed to confirm the inference of the study. No doubt lightning protection is taken care of in wind turbines.
    Dr.A.Jagadeesh Nellore(AP),India
    Wind Energy Expert
    E-mail: anumakonda.jagadeesh@gmail.com

    Link to this
  11. 11. tuned 11:21 am 03/4/2014

    Tesla would have captured it.

    Link to this
  12. 12. SAULT18 2:38 pm 03/4/2014

    Re: jtdwyer

    The study I posted shows that wind turbines are lasting longer than expected. I just knew that the pro-pollution crowd around here would use this SciAm article to claim that every single wind turbine instantly gets hit with lightning and fails within 5 minutes of being installed or some other nonsense. I should have clarified that if lightning was such a big problem for wind turbines, it definitely wasn’t showing up in the long-term data on their performance. Lighting strikes in the UK as well, although data from the U.S. midwest would also be useful.

    Link to this
  13. 13. SAULT18 2:42 pm 03/4/2014

    Re: phalaris

    “The news you post is fantastic: it means we won’t screwed for subsidies any longer for wind, and the network operators won’t be forced to take its useless output when they don’t want it.”

    While you are mostly incoherent, I would ask you to provide proof of your accusations against wind power and to try and put the tiny renewable energy tax breaks in perspective since fossil fuels are subsidized to the tune of $1.9 TRILLION annually:

    http://www.imf.org/external/np/pp/eng/2013/012813.pdf

    Again, proof should be from a respected source, while polluter front-groups and opinion blogs are definitely NOT in this category.

    Link to this
  14. 14. SAULT18 2:47 pm 03/4/2014

    Re: Carlyle #5

    For once, he’s speechless!

    Link to this
  15. 15. Carlyle 4:02 pm 03/4/2014

    Just being mindful of your health. Do not wish to feed your paranoia over what looks like an interesting but mostly non issue.

    Link to this
  16. 16. phalaris 5:23 am 03/5/2014

    Sault –
    will this source do?
    http://www.economist.com/news/europe/21594336-germanys-new-super-minister-energy-and-economy-has-his-work-cut-out-sunny-windy-costly
    Quote from it :
    ” the Energiewende has so far increased, not decreased, emissions of greenhouse gases”

    Link to this
  17. 17. David Cummings 6:59 am 03/6/2014

    But thermodynamics is just a social construct, created by the ruling white power structure to perpetuate the dominant paradigm of male phallocentric oppression and miscellaneous hegemonies.

    Link to this
  18. 18. Wayne Williamson 6:14 pm 03/6/2014

    This is soo cool. It’s kind of like that wheel that you turn to generate high voltages. Static electricity to the n’th level.

    Link to this
  19. 19. ecstatist 6:40 pm 03/10/2014

    The blades are “fiber glass” (GRP glass/carbon re-enforced plastic) with the copper lightning conductor embedded inside so as to keep a clean profile. It is usually exposed at the tip, sometimes with a copper capping sheath. If the blade is struck at the tip, little if any damage is done. If struck anywhere (on the blade) the lightning (electrons) burrow through to the copper and will almost always do some (usually inconsequential) local damage due to the heating effect of the current traversing a high resistance. At the hub, there is a copper slip-ring with carbon brushes although when struck there is usually a short arc parallel to the brushes as the brushes aren’t really sized to carry the full current. Lightning conductors are “working” even when they are not struck, by bleeding off electrons which reduces the potential between ground and the atmosphere. Look up St Elmo’s Fire.
    Which reminds me: I always ask proselytizing religious people why they always have lightning conductors on their places of worship. Surely that is displaying a shameful “lack of faith!” The hypocrites have no answer! (Especially as lightning is the classic god weapon)

    Link to this

Add a Comment
You must sign in or register as a ScientificAmerican.com member to submit a comment.

More from Scientific American

Scientific American Back To School

Back to School Sale!

12 Digital Issues + 4 Years of Archive Access just $19.99

Order Now >

X

Email this Article



This function is currently unavailable

X