6 ms·

Google is ramping up hiring for its plan to make 'energy kites'

59 points by coloneltcb 11y ago

jacquesm 11y ago
> The division has said that its experimental technology can produce 50% more energy with 90% less materials than traditional wind turbines. That's really neat but how long will these devices last? And the newer generation wind turbines are absolute monsters, 7.6 MW in one turbine and at the tip 198 meters high, that's not so far from the 250 meters for these kites, you'd need 12 of the Makani devices to equal one Enercon E-126. (though the windshear would be a larger factor for a ground based machine)
- stevesearer 11y ago
  I wonder how much larger a Makani kite would need to be to equal the power generation of one of the Enercon turbines you've mentioned. It would also be interesting to know how they both perform in strong winds. Can one keep generating power while the other needs to pause?
  - jacquesm 11y ago
    The Enercons shut down for safety certain wind speeds and up to that point they will cut down their output (and thus their RPM) by furling the blades. Most of these big machines are variable pitch. I'd assume that if the Makani kite gets close to its rated speeds that they'd winch it down to the ground for safety reasons. It would be quite annoying if a thing like that became unhinged starting at 250 meters or so. It could be carried quite a way before hitting the ground again.
- ChuckMcM 11y ago
  That is the million dollar question as power generation is driven not by acquisition cost but by the total operating costs. One of the challenges with the big turbines is you lose a lot of capacity with one of them off line, and it is there perhaps that kites have a small advantage.
  - jacquesm 11y ago
    Big turbines are big because of one simple thing: efficiency. It takes a lot less in terms of materials and space to make a single 8 MW turbine than it takes to generate the same amount of power with a large number of smaller ones. Yes, if they go down you lose a large amount of capacity in one go, but that does not weigh against the cost of a large number of smaller turbines that will go down much more frequently with smaller losses (they still need to be repaired). Though the cost to repair them will likely be lower per instance the people doing the service still have to be called out. I love this google project and I'm really curious what will come out but what with wind being my life-long side interest and having seen a large number of fantastic designs come with a hurricane of fanfare and go again without a breeze I'm not going to bet on this until there is much more hard data to compare to 'conventional' systems. Three blade conventional machines are anything but, they're engineering marvels with a ton of materials science behind them, it took nearly 40 years to go from the 10 KW prototypes at Petten (in NH, NL), to the giants you see today. That's a lot of R&D invested over a very long period of time. Now these kites can leverage some of that knowledge and they no longer have to validate the concept of windpower for regular consumption, that trail has already been blazed so they should have an easier time of it. Here's to hoping that it works, and that it won't end up next to 'windtree' or the 'windbelt' or a hundred other revolutionary wind technologies that ended up being stillborn.
    - kragen 11y ago
      I love how HN news stories sometimes get near-top comments within hours from people who have spent years pushing the envelope on them! Maybe someone from Makani can comment too. The great thing about kites, to me, is that the "tower" — the great majority of the material in a normal windmill — is reduced to the minimum: just the material necessary to resist the tensile force that's driving the generator, with negligible sideloading. And that should make it feasible to harness wind power at kilometers of altitude. (250 meters is just the start!) You are surely correct that wearout and reliability curves on these things are going to be big unknowns until we have a few thousand kite-years of experience.
      - 11y ago
- jqm 11y ago
  It's certainty easier to haul 12 Kites to site than props for a 198 meter wind turbine. I'm thinking deployment might be easier as well. Plus, if one kite breaks you only lose part of the electrical output as opposed to a large machine going off line. I wonder if hauling the thing down by line and repairing it on the ground might be easier than climbing up a tower. I would think so but could be wrong. Of course a larger fleet of individual machines probably means more frequent (smaller) repairs so there is that. How high do birds fly? Could these maybe solve the bird killing problem traditional wind turbines have had? It's a cool idea. I'm excited.
  - jacquesm 11y ago
    Simple geese fly at FL 290...
  - mrinterweb 11y ago
    I would think the larger danger to birds would be running into the kites' high tension cables.
- brandmeyer 11y ago
  Just an FYI, when Makani says 50% more energy, they mean that they will have 50% higher capacity factor than a conventional wind turbine of the same power rating. IOW, if a typical 600 kW wind turbine has a capacity factor of 40% at a particular site, then the Makani 600 kW nameplate machine should get a 60% capacity factor at the same site.
leroy_masochist 11y ago
From the Makani FAQ: "Energy kites are also tested on sites that are far away from people, infrastructure and airplane flight paths." Makes me wonder how hard it is going to be in the future to manage a system in which there are a bunch of drones (some guided by humans, most not) and systems like Makani. Are we going to have to re-think the standards we currently have to ensure that flying things don't hit other flying things? Not a rhetorical question -- would love to hear from someone whose job involves thinking about this question rigorously.
- andreyf 11y ago
  That's what regulators do: https://www.faa.gov/uas/ https://www.faa.gov/uas/
- jacquesm 11y ago
  Makani is tethered and - for now - apparently limited to about 250 meters, the height of a tall building.
  - mikeyouse 11y ago
    As a better comparison, the Transamerica Building in SF is 260M tall -- so more like the height of a very tall building..
- elihu 11y ago
  I think the way this all going to work in the end is that people will buy and sell right-of-ways in 3-dimensional space for their drones. There will be public right-of-ways for drones like there are public roads, and flight plans will be submitted electronically to the FAA for approval before any drone enters the public right-of-way. Energy kites should be pretty easy to deal with unless they're tethered within range of competing energy kites or things they could damage if they crashed.
  - brianwawok 11y ago
    Why not use what we already have? I.e. what if beyond every current road was a drone-zone from 300-500 feet up. Then we have drones not over private property, and easy to avoid this kind of thing... (But then routes get way less direct)
funkyy 11y ago
I wonder if they would put the resources and team in to making better ground based wind turbines, if they would achieve huge success as well. For me those kites are gizmos, but they must be quite dangerous compared to wind turbines - they are hazard for planes, helicopters and if one get loose it can cause huge damage. From all alternative sources I have seen so far the Hydrogen based energy looks best. You can burn it like gas, the production costs are not that high and you can make it quite easily. Connect solar panels to the mini factories in deserted area near water reservoirs and you get amazing way to creating clean energy. I have seen recently few videos of people that use Hydrogen as an energy in their homes and cars and it seems the technology is there since few decades and they are really easy to manufacture.

59 points by coloneltcb 11y ago

> The division has said that its experimental technology can produce 50% more energy with 90% less materials than traditional wind turbines. That's really neat but how long will these devices last? And the newer generation wind turbines are absolute monsters, 7.6 MW in one turbine and at the tip 198 meters high, that's not so far from the 250 meters for these kites, you'd need 12 of the Makani devices to equal one Enercon E-126. (though the windshear would be a larger factor for a ground based machine)

stevesearer 11y ago
I wonder how much larger a Makani kite would need to be to equal the power generation of one of the Enercon turbines you've mentioned. It would also be interesting to know how they both perform in strong winds. Can one keep generating power while the other needs to pause?
- jacquesm 11y ago
  The Enercons shut down for safety certain wind speeds and up to that point they will cut down their output (and thus their RPM) by furling the blades. Most of these big machines are variable pitch. I'd assume that if the Makani kite gets close to its rated speeds that they'd winch it down to the ground for safety reasons. It would be quite annoying if a thing like that became unhinged starting at 250 meters or so. It could be carried quite a way before hitting the ground again.
ChuckMcM 11y ago
That is the million dollar question as power generation is driven not by acquisition cost but by the total operating costs. One of the challenges with the big turbines is you lose a lot of capacity with one of them off line, and it is there perhaps that kites have a small advantage.
- jacquesm 11y ago
  Big turbines are big because of one simple thing: efficiency. It takes a lot less in terms of materials and space to make a single 8 MW turbine than it takes to generate the same amount of power with a large number of smaller ones. Yes, if they go down you lose a large amount of capacity in one go, but that does not weigh against the cost of a large number of smaller turbines that will go down much more frequently with smaller losses (they still need to be repaired). Though the cost to repair them will likely be lower per instance the people doing the service still have to be called out. I love this google project and I'm really curious what will come out but what with wind being my life-long side interest and having seen a large number of fantastic designs come with a hurricane of fanfare and go again without a breeze I'm not going to bet on this until there is much more hard data to compare to 'conventional' systems. Three blade conventional machines are anything but, they're engineering marvels with a ton of materials science behind them, it took nearly 40 years to go from the 10 KW prototypes at Petten (in NH, NL), to the giants you see today. That's a lot of R&D invested over a very long period of time. Now these kites can leverage some of that knowledge and they no longer have to validate the concept of windpower for regular consumption, that trail has already been blazed so they should have an easier time of it. Here's to hoping that it works, and that it won't end up next to 'windtree' or the 'windbelt' or a hundred other revolutionary wind technologies that ended up being stillborn.
  - kragen 11y ago
    I love how HN news stories sometimes get near-top comments within hours from people who have spent years pushing the envelope on them! Maybe someone from Makani can comment too. The great thing about kites, to me, is that the "tower" — the great majority of the material in a normal windmill — is reduced to the minimum: just the material necessary to resist the tensile force that's driving the generator, with negligible sideloading. And that should make it feasible to harness wind power at kilometers of altitude. (250 meters is just the start!) You are surely correct that wearout and reliability curves on these things are going to be big unknowns until we have a few thousand kite-years of experience.
    - 11y ago
jqm 11y ago
It's certainty easier to haul 12 Kites to site than props for a 198 meter wind turbine. I'm thinking deployment might be easier as well. Plus, if one kite breaks you only lose part of the electrical output as opposed to a large machine going off line. I wonder if hauling the thing down by line and repairing it on the ground might be easier than climbing up a tower. I would think so but could be wrong. Of course a larger fleet of individual machines probably means more frequent (smaller) repairs so there is that. How high do birds fly? Could these maybe solve the bird killing problem traditional wind turbines have had? It's a cool idea. I'm excited.
- jacquesm 11y ago
  Simple geese fly at FL 290...
- mrinterweb 11y ago
  I would think the larger danger to birds would be running into the kites' high tension cables.
brandmeyer 11y ago
Just an FYI, when Makani says 50% more energy, they mean that they will have 50% higher capacity factor than a conventional wind turbine of the same power rating. IOW, if a typical 600 kW wind turbine has a capacity factor of 40% at a particular site, then the Makani 600 kW nameplate machine should get a 60% capacity factor at the same site.

leroy_masochist 11y ago

From the Makani FAQ: "Energy kites are also tested on sites that are far away from people, infrastructure and airplane flight paths." Makes me wonder how hard it is going to be in the future to manage a system in which there are a bunch of drones (some guided by humans, most not) and systems like Makani. Are we going to have to re-think the standards we currently have to ensure that flying things don't hit other flying things? Not a rhetorical question -- would love to hear from someone whose job involves thinking about this question rigorously.

andreyf 11y ago
That's what regulators do: https://www.faa.gov/uas/ https://www.faa.gov/uas/
jacquesm 11y ago
Makani is tethered and - for now - apparently limited to about 250 meters, the height of a tall building.
- mikeyouse 11y ago
  As a better comparison, the Transamerica Building in SF is 260M tall -- so more like the height of a very tall building..
elihu 11y ago
I think the way this all going to work in the end is that people will buy and sell right-of-ways in 3-dimensional space for their drones. There will be public right-of-ways for drones like there are public roads, and flight plans will be submitted electronically to the FAA for approval before any drone enters the public right-of-way. Energy kites should be pretty easy to deal with unless they're tethered within range of competing energy kites or things they could damage if they crashed.
- brianwawok 11y ago
  Why not use what we already have? I.e. what if beyond every current road was a drone-zone from 300-500 feet up. Then we have drones not over private property, and easy to avoid this kind of thing... (But then routes get way less direct)

funkyy 11y ago

I wonder if they would put the resources and team in to making better ground based wind turbines, if they would achieve huge success as well. For me those kites are gizmos, but they must be quite dangerous compared to wind turbines - they are hazard for planes, helicopters and if one get loose it can cause huge damage. From all alternative sources I have seen so far the Hydrogen based energy looks best. You can burn it like gas, the production costs are not that high and you can make it quite easily. Connect solar panels to the mini factories in deserted area near water reservoirs and you get amazing way to creating clean energy. I have seen recently few videos of people that use Hydrogen as an energy in their homes and cars and it seems the technology is there since few decades and they are really easy to manufacture.