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Google Makani – Wind Energy Kites

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Re: Google Makani – Wind Energy Kites

#21

Post by jemofthewest »

grownseed wrote: post #4

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…

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.

Re: Google Makani – Wind Energy Kites

#23

Post by jemofthewest »

robinhowlett wrote: post #22

Would it plummet out of the sky if the wind dropped suddenly?

At the altitude these will be flying at, the wind is pretty consistent compared to the wind at ground level we're used to. However, I would imagine that the on-board controller could kick on it's propellers or something if the altitude changes too much.

Re: Google Makani – Wind Energy Kites

#25

Post by krschultz »

grownseed wrote: post #17
krschultz wrote: post #9

Earlier quoted context omitted.

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…

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 don…

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.

Re: Google Makani – Wind Energy Kites

#26

Post by plug »

krschultz wrote: post #9
grownseed wrote: post #4

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…

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…

Me neither, I'd be interested to hear more. I understand that 25 years is their lifespan. There was an interesting HN submission recently that discussed the problem of what to do with the blades once they reach EOL. Obviously they are very large and very hard to recycle due to the materials they are made from - a problem that increases with scale of course.

Like everything, I'm sure turbine blade tech will iterate. I recall hearing once that solar panels weren't viable because they didn't last long enough to recoup the energy cost it took to build them. I don't believe this is the case any more though?

Re: Google Makani – Wind Energy Kites

#27

Post by cwal37 »

giggles_giggles wrote: post #20
krschultz wrote: post #9

Earlier quoted context omitted.

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…

My understanding is that, among other things, the generators come under extreme stress during exceptionally windy occasions, causing a lot of wear and tear that happens way up at the top of these giant windmills. These require a lot of manual maintenance, which is dangerous and expensive due to the nature (and location) of the work. Additionally (and as a demonstration of just how much stress they come under), while…

What government agencies are out there mass-building wind? In terms of America at least, that's not how our generation system is set up.

Also, the recently-published Wind Vision[1] runs with an expected 20-year lifetime, and starts digging into system reliability specifics on page 70. Wind Vision was a lengthy collaborative process with industry, the labs, and DOE HQ. Good news is that there have been significant reliability gains in the gearboxes, generators, and electrical systems.

[1] http://www.energy.gov/windvision .pdfs are on the right.

Re: Google Makani – Wind Energy Kites

#28

Post by ChuckMcM »

I think this is pretty cool, but several questions spring to mind which I haven't found good answers for.

The first is what sort of density can you get out of these? How many per acre/hectare? 1? 3? California has a number of wind installations and some of them are pretty dense [1].

The second is what sort of radar signature does this thing have? Probably not a navigation hazard but should be interesting on the weather doppler display.

[1] http://www.jamielaval.com/Images2011/Journal/Tehachapi_windm...

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