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Please correct me if I'm wrong, but I was under the impression that wind turbines were effectively unsustainable due to the materials they are made of and their

Please correct me if I'm wrong, but I was under the impression that wind turbines were effectively unsustainable due to the materials they are made of and their actual lifespan not offsetting the initial financial and environmental costs. Now, I understand that this project is supposed to provide greater versatility and efficiency using cheaper materials, but it seems to me (by no means an expert on the subject) that these kites are considerably more prone to damage by their very nature too. Honest question, is this really solving a problem? P.S.: this website is absolutely horrible to navigate.

josefresco 12y ago
"effectively unsustainable" Got any data or a link to a resource that will back this claim up?
- Mandatum 12y ago
  I think in comparison to existing fossil fuels (price/ROI), in this WIki article they talk about how the drop of oil price meant funding for these types of projects went away: https://en.wikipedia.org/wiki/High-altitude_wind_power https://en.wikipedia.org/wiki/High-altitude_wind_power
krschultz 12y ago
I've never heard the argument that current wind turbine are unsustainable before. I don't see why that would be so. The base is concrete, the tower is steel, neither of which is exotic. The generator is pretty standard. All of that is industrial tech we invented a century ago, and we know how to maintain it for the long haul. The blades themselves are composite, that may have some longevity issues (you typically need to paint carbon fiber to prevent UV degradation every view years), but I don't know, they can last for a long time. Fiberglass boats last 50+ years. I would imagine the designed lifecycle of a wind turbine is 25+ years, and I also imagine that the bases will last long beyond that. In 50 years we may have to go around and replace the blades on these things, but that's it.
- grownseed 12y ago
  Thank you for your reply. I used to live in Scotland where there are a lot of wind turbines and I remember controversy in the news about the fact that while the expected lifespan of a wind turbine should be around 20 years, the actual lifespan ended up being in the region of 12 years, and the long-term maintenance costs ended up being higher than expected. There was also controversy about the environmental damage done to forests and birds, as well as noise pollution, though I guess this isn't directly related to the subject at hand. Please don't get me wrong, I'm all in favor of clean energy, I'm genuinely trying to inform myself about the pros and cons of each solution.
  - krschultz 12y ago
    Well if you are talking about damage done to forests & noise pollution, then you are trying to capture the externalities of power production into its "true cost". I'm all for that, but if you decide to do that you also have to use the same methodology for coal, oil, nuclear, etc. Sorry birds, but I feel like the cost of every bird killed by a wind turbine pales in comparison to what a few mountain top removal coal mines do to an area. In terms of economic ROI for the corporations owning wind turbines, I think it works out even w/o tax credits. Obviously the tax credits help, but the credits are not generous enough to justify all of this investing on their own. I believe the companies have done the analysis and believe it is profitable.
    - jonathansizz 12y ago
      FYI: bird deaths via wind turbines are trivial. Collisions with wind turbines account for about one-tenth of one percent of all "unnatural" bird deaths in the United States each year. http://science.howstuffworks.com/environmental/green-science/wind-turbine-kill-birds.htm http://science.howstuffworks.com/environmental/green-science...
      - lotsofmangos 12y ago
        I was thinking about starting the anti-windows party to campaign for banning glass in architecture, just to see how dedicated people are to the premise of reducing bird deaths caused by human structures.
antr 12y ago
> effectively unsustainable due to the materials they are made of and their actual lifespan not offsetting the initial financial and environmental costs I don't know where you got the information from, but I can assure you that that is not the case. Wind is extremely sustainable, even if we factor in the carbon footprint of the production and construction of the wind farm.
beat 12y ago
I'm fairly certain you're wrong about that. A quick googling suggests that a commercial wind turbine produces about 1M kWh/year, more or less. That's a great deal more energy than it would require to manufacture and install. By comparison, it takes about a pound of coal to produce 1 kWh of electricity, more or less. So a single wind turbine produces the equivalent energy of a MILLION pounds of coal every year! How much does it cost to mine and transport that coal, not to mention the construction and operating costs of the plant? That said, what problem is this solving? Well, the core solution is converting to wind-based power. The kites are just a cost reduction for the conversion process. They presumably cost less to make than standard towers, and are easier and cheaper to install. They probably have long-term cost/kWh benefits as well.
- tjradcliffe 12y ago
  A MILLION pounds (which really should be said in a "Dr Evil" voice :-)) is 500 tons. A rail car carries 120 tons of coal. A typical 2 GWe thermal plant burns a rail car of coal every ~20 minutes (coal has ~30 MJ/kg, and there are ~1000 kg/ton, so 120100030E6 = 3.6E12 J/rail car, and 2 GWe ~ 4 GWth, which over 1000 seconds = 4E12 J) So by your figures, a windmill's yearly output is equivalent to a little over an hour's operation of a typical coal-fired plant. EDIT: 1 kWhr = 3.6 MJ, so a pound of coal produces closer to 10 kWhr than 1 (~20 kWhr thermal => 10 kWhr electric after efficiency correction), but the argument still stands. 9000 changed to 900 below. Windmills are great, and tech like this that increases load factor, lowers costs and extends their reach into more marginal areas is good, but it'll take almost 900 windmills to replace one coal plant, plus oodles of energy storage for when the wind isn't blowing. One coal plant, on the other hand, can be replaced by one nuclear plant, or a dozen-odd small nuclear plants of modern, modular, passively-safe design. People who believe anthropogenic climate change has a very significant chance of ending civilization should be pushing as hard as they possibly can in favour of nuclear power for this reason. If we had invested heavily in nuclear in the 70's and 80's we wouldn't be in this mess now. Nuclear is not without its costs, of course, but all industrial-scale power sources have costs, and no one is seriously proposing we end industrial civilization, so we need to decide which tradeoffs are acceptable. Solar capacity and wind both have roles to play, but it is very hard to escape a role for nuclear in replacing base-load coal.
lotsofmangos 12y ago
For the USA, the energy returned on energy invested for wind mostly beats oil and is more than twice a good as current photovoltaics. http://en.wikipedia.org/wiki/Energy_returned_on_energy_invested#/media/File:EROI_-_Ratio_of_Energy_Returned_on_Energy_Invested_-_USA.svg http://en.wikipedia.org/wiki/Energy_returned_on_energy_inves...
- maxerickson 12y ago
  I followed the sources there and cherry picked one actual study (in the sense that I didn't even try to look at more than 1). The wikipedia citation cites this meta analysis for the number: http://www.soest.hawaii.edu/GG/FACULTY/ITO/GG410/Wind/Kubiszewski_EROI_Wind_RenEn10.pdf http://www.soest.hawaii.edu/GG/FACULTY/ITO/GG410/Wind/Kubisz... I then only looked at the first study from there that I found, linked here: https://www.google.com/search?q=energy+performance+and+life+cycle+assessment+of+an+Italian+wind+farm.+Renewable+and+Sustainable+Energy+Reviews+2008 https://www.google.com/search?q=energy+performance+and+life+... They estimated the lifetime of the farm they studied, and estimated the maintenance and decommissioning costs. Those estimates are probably going to be reasonable, but they are estimates.
  - lotsofmangos 12y ago
    All numbers regarding things that will happen in the future tend to be estimates, no matter which long term engineering project you care to pick. For fairly obvious reasons.
    - maxerickson 12y ago
      Sure, that's why I said Those estimates are probably going to be reasonable, because I don't think it is a problem that they are estimates. But it is sometimes nice to peer through the wikipedia and see what lies beneath.
      - lotsofmangos 12y ago
        Your point seemed to be that the first of the studies you picked was based on estimates for things like total lifetime and decommissioning. But the fact that the first thing you picked relied on estimates for those things tells us nothing at all about the quality of the data, just that estimates were used for something where estimates are always used.
jemofthewest 12y ago
One of the bigger issues with wind energy (solar also) that this solution doesn't address is the distribution. These energy sources don't have consistent output, and definitely do not match peak requirements. In other words, at times they will produce far more than needed and others far less. The solution to this could be smart grids and energy storage, neither of which are really at a feasible point at scale yet. But we're getting there.
- beat 12y ago
  Baseline + peak load grids is a much more complex problem. But that said, it doesn't mean wind isn't helpful or useful - it just means some grid design change. Consider this - any energy captured from wind can be stored, at some known percentage of loss due to thermal and other inefficiencies. Heck, wind a spring with it! This is going to be less efficient, but not orders of magnitude so - and it still keeps us on clean and relatively inexpensive wind, as opposed to dirty and increasingly expensive fossil fuels.
dredmorbius 12y ago
EROEI of wind turbines is about 20:1. That is, you recover 20x the energy that goes into constructing and maintaining the turbines over their lifespan. The argument that some of the materials used in turbine manufacture presently rely on fossil fuels (e.g., coal used for coking steel) doesn't mean that other options for such processes aren't possible. Though shortages of fuelwood were among the key reasons for switching from fuelwood to coal in the first place in the 1600s-1700s.
- tjradcliffe 12y ago
  Metallurgical coal is going to be the very hardest thing to get away from. Improvements in the coking process (carbon capture) are plausible, but the chemistry basically demands burning a butt-load of carbon. Thermal coal is replaceable by conservation, nuclear power, and to some extent wind/solar plus storage, and if I were in charge I'd be pushing to ban new thermal coal development. But metallurgical coal is going to be almost physically (or chemically) impossible to replace.
  - dredmorbius 12y ago
    It's a a big use, 14% of global coal use from memory based on a recent query. BP's annual energy review 2014 gives total global coal use as 3,881.4 Mtoe (million tons of oil equivalent), which works out to 5.54 billion tonnes of coal. 14% of that is still a large number, 776 million tons. I happened to look up total forestry production in the US recently, let's see if I can't find that .... Here: https://plus.google.com/104092656004159577193/posts/NVg1UQ5WNAh https://plus.google.com/104092656004159577193/posts/NVg1UQ5W... Total US lumber production is equivalent to 928 Mboe. So, yeah, applying 84% of US timber production to coking activities would supply the world with steel. (Sources: http://www.loggers.com/timber_facts.htm http://www.loggers.com/timber_facts.htm http://www.fpl.fs.fed.us/documnts/fplrp/fplrp615/fplrp615.pdf http://www.fpl.fs.fed.us/documnts/fplrp/fplrp615/fplrp615.pd... http://generatorjoe.net/html/energy.asp http://generatorjoe.net/html/energy.asp ) US steel production is just under 100 megatonnes (2007). Global production is 1,600 megatonnes. So US production is 6.25% of global. The US could provide for its own steel manufacture somewhat more feasibly. http://www.worldsteel.org/media-centre/press-releases/2014/World-crude-steel-output-increases-by-3-5--in-2013.html http://www.worldsteel.org/media-centre/press-releases/2014/W... http://www.indexmundi.com/minerals/?country=us&product=raw-steel http://www.indexmundi.com/minerals/?country=us&product=raw-s... Incidentally, energy use in producing construction materials is among the reasons I see a possible future not for biofuels but for biomaterials -- utilizing plants or organic processes to directly provide structural materials (or replacements for them) that we use. Carbon separation from seawater seems another possible approach, though I haven't specced out that for coking purposes: https://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy_electricitytofuel_synthesis_papers_and/ https://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy...
allworknoplay 12y ago
The materials you're probably talking about are rare earth magnets used in their bearings -- the jury is kind of out on their sustainability since they're rare and depletable but highly likely to be recycled at the end of a turbine's life. The lifespan questions are different -- wind and constant mechanical motion put a lot of stress on turbines and I believe as some other commenters pointed out that the actual lifespans often haven't measured up to the predicted ones. Makani's capex for a kite should be pretty low; as I recall, talking to Saul like 8 years ago, the difficulty was in stable control of the tethers, not in the economics if control was achieved. But who knows where they're at now (or even exactly how good my recall is).

josefresco 12y ago

"effectively unsustainable" Got any data or a link to a resource that will back this claim up?

Mandatum 12y ago
I think in comparison to existing fossil fuels (price/ROI), in this WIki article they talk about how the drop of oil price meant funding for these types of projects went away: https://en.wikipedia.org/wiki/High-altitude_wind_power https://en.wikipedia.org/wiki/High-altitude_wind_power

krschultz 12y ago

I've never heard the argument that current wind turbine are unsustainable before. I don't see why that would be so. The base is concrete, the tower is steel, neither of which is exotic. The generator is pretty standard. All of that is industrial tech we invented a century ago, and we know how to maintain it for the long haul. The blades themselves are composite, that may have some longevity issues (you typically need to paint carbon fiber to prevent UV degradation every view years), but I don't know, they can last for a long time. Fiberglass boats last 50+ years. I would imagine the designed lifecycle of a wind turbine is 25+ years, and I also imagine that the bases will last long beyond that. In 50 years we may have to go around and replace the blades on these things, but that's it.

grownseed 12y ago
Thank you for your reply. I used to live in Scotland where there are a lot of wind turbines and I remember controversy in the news about the fact that while the expected lifespan of a wind turbine should be around 20 years, the actual lifespan ended up being in the region of 12 years, and the long-term maintenance costs ended up being higher than expected. There was also controversy about the environmental damage done to forests and birds, as well as noise pollution, though I guess this isn't directly related to the subject at hand. Please don't get me wrong, I'm all in favor of clean energy, I'm genuinely trying to inform myself about the pros and cons of each solution.
- krschultz 12y ago
  Well if you are talking about damage done to forests & noise pollution, then you are trying to capture the externalities of power production into its "true cost". I'm all for that, but if you decide to do that you also have to use the same methodology for coal, oil, nuclear, etc. Sorry birds, but I feel like the cost of every bird killed by a wind turbine pales in comparison to what a few mountain top removal coal mines do to an area. In terms of economic ROI for the corporations owning wind turbines, I think it works out even w/o tax credits. Obviously the tax credits help, but the credits are not generous enough to justify all of this investing on their own. I believe the companies have done the analysis and believe it is profitable.
  - jonathansizz 12y ago
    FYI: bird deaths via wind turbines are trivial. Collisions with wind turbines account for about one-tenth of one percent of all "unnatural" bird deaths in the United States each year. http://science.howstuffworks.com/environmental/green-science/wind-turbine-kill-birds.htm http://science.howstuffworks.com/environmental/green-science...
    - lotsofmangos 12y ago
      I was thinking about starting the anti-windows party to campaign for banning glass in architecture, just to see how dedicated people are to the premise of reducing bird deaths caused by human structures.

antr 12y ago

> effectively unsustainable due to the materials they are made of and their actual lifespan not offsetting the initial financial and environmental costs I don't know where you got the information from, but I can assure you that that is not the case. Wind is extremely sustainable, even if we factor in the carbon footprint of the production and construction of the wind farm.

beat 12y ago

I'm fairly certain you're wrong about that. A quick googling suggests that a commercial wind turbine produces about 1M kWh/year, more or less. That's a great deal more energy than it would require to manufacture and install. By comparison, it takes about a pound of coal to produce 1 kWh of electricity, more or less. So a single wind turbine produces the equivalent energy of a MILLION pounds of coal every year! How much does it cost to mine and transport that coal, not to mention the construction and operating costs of the plant? That said, what problem is this solving? Well, the core solution is converting to wind-based power. The kites are just a cost reduction for the conversion process. They presumably cost less to make than standard towers, and are easier and cheaper to install. They probably have long-term cost/kWh benefits as well.

tjradcliffe 12y ago
A MILLION pounds (which really should be said in a "Dr Evil" voice :-)) is 500 tons. A rail car carries 120 tons of coal. A typical 2 GWe thermal plant burns a rail car of coal every ~20 minutes (coal has ~30 MJ/kg, and there are ~1000 kg/ton, so 120100030E6 = 3.6E12 J/rail car, and 2 GWe ~ 4 GWth, which over 1000 seconds = 4E12 J) So by your figures, a windmill's yearly output is equivalent to a little over an hour's operation of a typical coal-fired plant. EDIT: 1 kWhr = 3.6 MJ, so a pound of coal produces closer to 10 kWhr than 1 (~20 kWhr thermal => 10 kWhr electric after efficiency correction), but the argument still stands. 9000 changed to 900 below. Windmills are great, and tech like this that increases load factor, lowers costs and extends their reach into more marginal areas is good, but it'll take almost 900 windmills to replace one coal plant, plus oodles of energy storage for when the wind isn't blowing. One coal plant, on the other hand, can be replaced by one nuclear plant, or a dozen-odd small nuclear plants of modern, modular, passively-safe design. People who believe anthropogenic climate change has a very significant chance of ending civilization should be pushing as hard as they possibly can in favour of nuclear power for this reason. If we had invested heavily in nuclear in the 70's and 80's we wouldn't be in this mess now. Nuclear is not without its costs, of course, but all industrial-scale power sources have costs, and no one is seriously proposing we end industrial civilization, so we need to decide which tradeoffs are acceptable. Solar capacity and wind both have roles to play, but it is very hard to escape a role for nuclear in replacing base-load coal.

lotsofmangos 12y ago

For the USA, the energy returned on energy invested for wind mostly beats oil and is more than twice a good as current photovoltaics. http://en.wikipedia.org/wiki/Energy_returned_on_energy_invested#/media/File:EROI_-_Ratio_of_Energy_Returned_on_Energy_Invested_-_USA.svg http://en.wikipedia.org/wiki/Energy_returned_on_energy_inves...

maxerickson 12y ago
I followed the sources there and cherry picked one actual study (in the sense that I didn't even try to look at more than 1). The wikipedia citation cites this meta analysis for the number: http://www.soest.hawaii.edu/GG/FACULTY/ITO/GG410/Wind/Kubiszewski_EROI_Wind_RenEn10.pdf http://www.soest.hawaii.edu/GG/FACULTY/ITO/GG410/Wind/Kubisz... I then only looked at the first study from there that I found, linked here: https://www.google.com/search?q=energy+performance+and+life+cycle+assessment+of+an+Italian+wind+farm.+Renewable+and+Sustainable+Energy+Reviews+2008 https://www.google.com/search?q=energy+performance+and+life+... They estimated the lifetime of the farm they studied, and estimated the maintenance and decommissioning costs. Those estimates are probably going to be reasonable, but they are estimates.
- lotsofmangos 12y ago
  All numbers regarding things that will happen in the future tend to be estimates, no matter which long term engineering project you care to pick. For fairly obvious reasons.
  - maxerickson 12y ago
    Sure, that's why I said Those estimates are probably going to be reasonable, because I don't think it is a problem that they are estimates. But it is sometimes nice to peer through the wikipedia and see what lies beneath.
    - lotsofmangos 12y ago
      Your point seemed to be that the first of the studies you picked was based on estimates for things like total lifetime and decommissioning. But the fact that the first thing you picked relied on estimates for those things tells us nothing at all about the quality of the data, just that estimates were used for something where estimates are always used.

jemofthewest 12y ago

One of the bigger issues with wind energy (solar also) that this solution doesn't address is the distribution. These energy sources don't have consistent output, and definitely do not match peak requirements. In other words, at times they will produce far more than needed and others far less. The solution to this could be smart grids and energy storage, neither of which are really at a feasible point at scale yet. But we're getting there.

beat 12y ago
Baseline + peak load grids is a much more complex problem. But that said, it doesn't mean wind isn't helpful or useful - it just means some grid design change. Consider this - any energy captured from wind can be stored, at some known percentage of loss due to thermal and other inefficiencies. Heck, wind a spring with it! This is going to be less efficient, but not orders of magnitude so - and it still keeps us on clean and relatively inexpensive wind, as opposed to dirty and increasingly expensive fossil fuels.

dredmorbius 12y ago

EROEI of wind turbines is about 20:1. That is, you recover 20x the energy that goes into constructing and maintaining the turbines over their lifespan. The argument that some of the materials used in turbine manufacture presently rely on fossil fuels (e.g., coal used for coking steel) doesn't mean that other options for such processes aren't possible. Though shortages of fuelwood were among the key reasons for switching from fuelwood to coal in the first place in the 1600s-1700s.

tjradcliffe 12y ago
Metallurgical coal is going to be the very hardest thing to get away from. Improvements in the coking process (carbon capture) are plausible, but the chemistry basically demands burning a butt-load of carbon. Thermal coal is replaceable by conservation, nuclear power, and to some extent wind/solar plus storage, and if I were in charge I'd be pushing to ban new thermal coal development. But metallurgical coal is going to be almost physically (or chemically) impossible to replace.
- dredmorbius 12y ago
  It's a a big use, 14% of global coal use from memory based on a recent query. BP's annual energy review 2014 gives total global coal use as 3,881.4 Mtoe (million tons of oil equivalent), which works out to 5.54 billion tonnes of coal. 14% of that is still a large number, 776 million tons. I happened to look up total forestry production in the US recently, let's see if I can't find that .... Here: https://plus.google.com/104092656004159577193/posts/NVg1UQ5WNAh https://plus.google.com/104092656004159577193/posts/NVg1UQ5W... Total US lumber production is equivalent to 928 Mboe. So, yeah, applying 84% of US timber production to coking activities would supply the world with steel. (Sources: http://www.loggers.com/timber_facts.htm http://www.loggers.com/timber_facts.htm http://www.fpl.fs.fed.us/documnts/fplrp/fplrp615/fplrp615.pdf http://www.fpl.fs.fed.us/documnts/fplrp/fplrp615/fplrp615.pd... http://generatorjoe.net/html/energy.asp http://generatorjoe.net/html/energy.asp ) US steel production is just under 100 megatonnes (2007). Global production is 1,600 megatonnes. So US production is 6.25% of global. The US could provide for its own steel manufacture somewhat more feasibly. http://www.worldsteel.org/media-centre/press-releases/2014/World-crude-steel-output-increases-by-3-5--in-2013.html http://www.worldsteel.org/media-centre/press-releases/2014/W... http://www.indexmundi.com/minerals/?country=us&product=raw-steel http://www.indexmundi.com/minerals/?country=us&product=raw-s... Incidentally, energy use in producing construction materials is among the reasons I see a possible future not for biofuels but for biomaterials -- utilizing plants or organic processes to directly provide structural materials (or replacements for them) that we use. Carbon separation from seawater seems another possible approach, though I haven't specced out that for coking purposes: https://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy_electricitytofuel_synthesis_papers_and/ https://www.reddit.com/r/dredmorbius/comments/22k71x/us_navy...

allworknoplay 12y ago

The materials you're probably talking about are rare earth magnets used in their bearings -- the jury is kind of out on their sustainability since they're rare and depletable but highly likely to be recycled at the end of a turbine's life. The lifespan questions are different -- wind and constant mechanical motion put a lot of stress on turbines and I believe as some other commenters pointed out that the actual lifespans often haven't measured up to the predicted ones. Makani's capex for a kite should be pretty low; as I recall, talking to Saul like 8 years ago, the difficulty was in stable control of the tethers, not in the economics if control was achieved. But who knows where they're at now (or even exactly how good my recall is).