Jump to content

Makani Power generating kites


jhn.holgate

Recommended Posts

Google has bought Makani Power, which is developing a kite powered generator - a tethered kite or wing that has turbines on top to create power.  A very weird looking beastie indeed.

makani-power-1024x682.jpg

makani-google-x-energy-alternative_h.jpg

There's a demo video here:

 

And an actual in-use video here:

Story here: Link to news article

I suppose a kite is really just a wing.  And if you tether a wing, does it become a kite?  Either way, very nice to see some technical development going on in power generation from kites.  

Edited by jhn.holgate
Link to comment
Share on other sites

I'm not sure of the benefit over traditional wind turbines (I'm sure Tony wont like them!), I guess clean wind at 800 feet - but if it increases is it bye bye kite and truck? And if it drops I guess the robot kite turns the turbine into motors and powers the "kite" to a safe landing?

Edit: Ok, I've now watched the videos with the sound! Still not sure of the benefits!

I think these guys had the best idea when it comes to tethered flying...

http://www.extremekites.com.au/topic/15308-flexifoil-stacker-extreme-stunt/#comment-138399 

Edited by gum-nuts
Link to comment
Share on other sites

Being solid wing with control surfaces it could depower significantly more than a kite. I have not looked in detail how many lines go up to the wing, but would imagine the wing is controlled more like an aeorplane rather than kite lines which need to be under tension through the full depower range. I've looked closelr now, just the one line to the wing. 

Edited by SoutherlyBuster
Link to comment
Share on other sites

So did any one spot the what on first inspection appears to be an error on the Makani promotional web site? They claim that if the wind speed goes up by a factor 2, the power is increased by a factor 8, to me that does not make sense. It is well know if the apparent wind speed goes up by a factor 2, the net load goes up by a factor of 2^2=4, so where does x8 come from? Not that I have done the calcs, but perhaps the apparent wind is not proportional to the wind speed.

The other thing that looks a bit strange is the wind speed map of the world. According to this the wind speed at 100m elevation (for conventional wind turbines) is zero in most of Queensland, that would mean no one kite surfs there which we all know is wrong. Then for the makani at 250m elevation the wind speed in QLD then jumps up to 6 to 7 m/s.

Link to comment
Share on other sites

So did any one spot the what on first inspection appears to be an error on the Makani promotional web site? They claim that if the wind speed goes up by a factor 2, the power is increased by a factor 8, to me that does not make sense. It is well know if the apparent wind speed goes up by a factor 2, the net load goes up by a factor of 2^2=4, so where does x8 come from? Not that I have done the calcs, but perhaps the apparent wind is not proportional to the wind speed.

The other thing that looks a bit strange is the wind speed map of the world. According to this the wind speed at 100m elevation (for conventional wind turbines) is zero in most of Queensland, that would mean no one kite surfs there which we all know is wrong. Then for the makani at 250m elevation the wind speed in QLD then jumps up to 6 to 7 m/s.

There are 4 turbines so does that make it a factor of 8?:D

As wind speed doubles the actual force increases dramatically. 

An easy calc I use is 5 knots x 5 =25.

7 knots x 7 =49, so 7 knots has twice the power of 5 knots and so on.

This seems to make it easier for me to get my head round what kite/sail I choose, for the guestimate of the actual wind strength.

Edited by Chook
Link to comment
Share on other sites

  • 5 years later...

So if you ever wanted to go to the extreme high tech end of kite production... Now you can.

Makani recently closed after too many crashes and not enough power production.

However on closing, they did the right thing and open sourced a huge data archive.

There's production schemes, tests, software, patents loads all open now. https://x.company/projects/makani/

It's good to share... But I still think they were mental. (Pals, I can say that) They chose an unscalable architecture.

Should have gone networked kites like kite turbines instead bro.

Link to comment
Share on other sites

6 hours ago, roddyread said:

There's production schemes, tests, software, patents loads all open now. https://x.company/projects/makani/

First of all I have no idea how you remembered this discussion, well done :D 

That page is full of some great info, I stumbled over the feature video at the bottom.  When this was originally I didn't actually realise the scale/size of these things!

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...