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Noel Laporte

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What form of renewable energy has or will have the lowest impact on biodiversity?

Climate change, air pollution, rising sea levels and species extinction can all be attributed to the increasing usage of non-renewable energy in the world today. Non-renewable energy reserves are diminishing and finite with an ever-increasing demand from countries around the world. Coal, natural gas and oil all have detrimental effects on the environment. These effects are both local and global, harming species throughout the world. As we consider different renewable forms of energy, can we rank their potential impacts on biodiversity?


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    Apr 23 2013: When I first started thinking about this question, solar power immediately provided one of the most attractive possibilities as a biologically low impact alternative energy source. In my thinking, the best case scenario for solar would be found not in large plants which require dedicated plots of land, but rather in an army of individual panels put in place within and throughout cities. This best case solar scenario would be fantastic as it would conceivably cause no further ecological impact in terms of land and water use than the cities themselves do already. But, as Chelsea pointed out the solar panels required for this project are currently expensive and inefficient so this idea is not really a doable one at this point in time.
    That said, I did some more research and discovered an even more promising dream technology: flying windmills. Basically what this would entail is the construction of huge kites with propeller blades which are tethered to the ground, flown up a few miles into the air at which point their propellers switch from being active to passive at which point their free spinning blades would generate electricity and transfer it down their tether and into the electrical grid. Sitting a few miles up where the air currents are quite strong, the blades would be able to generate up to 250 times the power of an identical turbine near the ground according to calculations done by Cristina Archer and Mark Jacobson of Stanford University (1). Of course this project is far from perfect and really just a dream at this point, but advancements are being made. At least one company, Makani Power, is running with the idea, and has so far created a few small scale gliders which do in fact generate power using this approach (2). So maybe not so crazy after all?
    1. http://discovermagazine.com/2008/oct/24-high-flying-windmills-blow-away-their-ground-based-cousins#.UXYC-7XFWSo

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      Apr 23 2013: How do you think flying windmills would impact bird populations and bird diversity?
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        Apr 23 2013: I can't think of it as being that big of a problem since the windmills would be at such high elevations. Also since birds nest on the ground the only way I can see them affecting the birds is through disruption of migration patterns. I see it as relatively analogous to airplanes, which birds have little trouble avoiding by and large. Though these windmills could conceivably be more densely concentrated in an area and larger in size overall, I'm not sure that they would trouble birds much.
        The largest effect I can see them having is through disruption of insects which have been shown to fly above even airliner traffic (1).

        1. http://www.npr.org/blogs/krulwich/2011/06/01/128389587/look-up-the-billion-bug-highway-you-cant-see
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          Apr 23 2013: I agree with Erik. I would imagine a fast moving and extremely strong jet turbine would be much more harmful to bird populations and diversity than windmills. Although there might be some negative impact on windmills to avian diversity I imagine slow big moving blades must less impacting. I'm curious to how different the impacts of dams and wind mills are to the injury or death of animals getting in contact with them.
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      Apr 23 2013: I don't know much about bird flight and how aircraft and other airborne technology impacts birds. Upon a quick search I found these. Thoughts?


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      Apr 23 2013: A paper by Barclay et al (Canadian Journal of Zoology, 2007) estimates about 6,000 annual deaths for birds and about the same for bats due to wind turbines in North America. Although these fatalities are due to turbines, not these flying windmills, I imagine they could have a similar impact. Birds and bats cand and do fly miles above the ground, so I don't think the high elevation of these flying windmills would help much in reducing deaths. Birds cannot see the rotating blades of wind turbines since they are spinning so quickly, and therefore birds can not simple migrate around these windmills (I think they more comparable in structure to wind turbines than huge obvious ariplanes.) Another problem I see with these flying windmills is disruption with aircrafts themselves.
      I think this idea is very unique (cool find!), but tests would have to be done to minimize the impact on flying organisms.
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        Apr 23 2013: Anna and Jessica,
        You both make good points about the dangers to birds from this technology. Some in depth studies would definitely have to be done to address that issue and try and find sites of the least impact. One suggestion mentioned in one of the articles I posted suggested basing the windmills at sea where I'm sure some spots could be found with lower biological impact than over land.
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          Apr 24 2013: I agree with your idea that wind energy is very clean and cost-effective. In order to minimize the bird deaths caused by wind development, some researchers find that a “bird risk assessment map” is a “must have” tool for wind development. This kind of map indicates both concentrated migratory pathways and habitat locations for each major bird species. For each location, there are numerous background information, such as habitat land use, land ownerships and conservation issues. Important sites and pathways are colored according to their importance to birds, and scientists identify over 2000 key sites that birds may be vulnerable from wind development. This map can provide some bird-smart energy sources and avoid wind development in high-impact and high-priority bird areas. As American Bird Conservatory (ABC) states, “this map offers a way to prevent millions of bird deaths from wind power, while at the same time providing ample opportunity for the prudent development of this potentially bird-smart energy source”. I think this method can be a good starting point for any consideration for newly wind energy construct. You can check out the “Wind Development Bird Risk Map” here,


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