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Makani source code released

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Re: Makani source code released

#81

Post by krisoft »

londons_explore wrote: post #77
tobinfricke wrote: post #34

Earlier quoted context omitted.

> The Makani "kite" turbine was 2000 lbs. Essentially the same code could run Makani's smaller machine, the 20 kilowatt "Wing 7", with a 7.8 meter wingspan and a mass of 60 kg. Many of the existing kite power companies are working on machines of this scale. But we did have the luxury to design and build the system from the ground up, whereas scrappier startups might have to cobble together existing components. Hopefu…

So what's to stop me cobbling together something like the Wing 7 and just leaving it unattended in a field to launch and generate whenever the wind conditions are suitable? If I did, and I got typical government subsidies for wind power, I might earn $10k/year. That ought to pay for all the machines parts if I buy everything hobby grade from AliExpress. The 2nd year is pure profit assuming the craft lasts that long.…

The FAA (or your local alternative) might want to check your paperwork and licensing too.

Re: Makani source code released

#82

Post by 317070 »

londons_explore wrote: post #77
tobinfricke wrote: post #34

Earlier quoted context omitted.

> The Makani "kite" turbine was 2000 lbs. Essentially the same code could run Makani's smaller machine, the 20 kilowatt "Wing 7", with a 7.8 meter wingspan and a mass of 60 kg. Many of the existing kite power companies are working on machines of this scale. But we did have the luxury to design and build the system from the ground up, whereas scrappier startups might have to cobble together existing components. Hopefu…

So what's to stop me cobbling together something like the Wing 7 and just leaving it unattended in a field to launch and generate whenever the wind conditions are suitable? If I did, and I got typical government subsidies for wind power, I might earn $10k/year. That ought to pay for all the machines parts if I buy everything hobby grade from AliExpress. The 2nd year is pure profit assuming the craft lasts that long.…

The issue is the tumbling cost of regular wind turbines, even offshore. If you have such a field, you would build a turbine, not a kite.

So yes, you could make a profit. But there is an alternative source of technology that makes the same power and has become really profitable in the last 10 years.

Re: Makani source code released

#83

Post by person_of_color »

tobinfricke wrote: post #61
person_of_color wrote: post #49

Earlier quoted context omitted.

And you?

I had the privilege of being part of the documentation team preparing some of the materials that were released yesterday (in particular: the code and the chapter on the autopilot/control system). Now I'm taking a little break but I hope to start something new around January. Definitely open to ideas. :-)

https://observer.com/2019/12/apple-new-satellite-project-wir...

Re: Makani source code released

#84

Post by tinco »

tobinfricke wrote: post #64
UncleOxidant wrote: post #3

It's cool that they open sourced this, but as someone who worked at a kite power company (a much smaller company with a much smaller kite) I'm not sure much here will be transferable to other companies. Makani was making a huge 2000 lb "kite" turbine. That requires the kind of money that Google could back them with - and since Google isn't funding this anymore I just don't see where this can go as none of the remaini…

While our code might be too specialized to help out other crosswind kite power companies in particular, I think the technical document might be quite impactful: https://storage.googleapis.com/x-prod.appspot.com/files/Maka... The chapter "Airborne Wind Turbine Performance" contains some sobering lessons for the field and deserves a close read.

Thank you so much for that document it's so interesting. Interesting lesson from the exec summary: The real world kite underperformed the model by nearly half, and from the numericals it seems like the main reasons we're that the turning radius was about double that what you were trying to get, and that the tether drag was a significant loss that was not accounted for. The next gen model would be the same span but with a larger area and with a shorter tether, the turning radius would be a lot smaller and it would effectively halve the drag and increase performance by 30% but it would still underperform the initial model by about 20%.

The general big conclusion as I get it is that because of these losses even though the kites are capable of getting more wind per kite, when area is constrained a conventional turbine seems to have better density.

The idea that the kites have lower installation cost offshore does seem interesting to me, but I only skimmed it so maybe that's offset by something else.

Re: Makani source code released

#85

Post by [deleted] »

tobinfricke wrote: post #71
grizzles wrote: post #66

Earlier quoted context omitted.

why wasn't the turbine hung off an airship?

This is actually a good question as it addresses the common misconception that the purpose of the kite was just to hold the propeller blades high up in the sky. In fact, having the kite fly like an airplane is a crucial part of the principle of operation. The documenary film ( https://makanifilm.com/ ) might help make this clear. There are airborne wind turbine concepts that use an aerostat (blimp/balloon). However,…

[deleted]

Re: Makani source code released

#87

Post by bayindirh »

nikitaga wrote: post #74
cloudwalking wrote: post #56

Earlier quoted context omitted.

X is what Google used to be.

X is still X and Google is still Google. Outside of X, Google was never known for crazy moonshots. Google was always an ad platform with a search engine.

X was Google X, now it's Alphabet X. Google was Google, now it's Alphabet Google.

Google was the name of the search engine and the company. Now the company name has changed, everything is restructured and Google is an ad platform with a search engine.

"X Development LLC. is an American semi-secret research and development facility and organization founded by Google in January 2010, which now operates as a subsidiary of Alphabet Inc. X has its headquarters about a mile and a half from Alphabet's corporate headquarters, the Googleplex, in Mountain View, California."[0]

[0]: https://en.wikipedia.org/wiki/X_(company)

Re: Makani source code released

#88

Post by gundmc »

karlding wrote: post #57
ComputerGuru wrote: post #53

Earlier quoted context omitted.

How do you find out about these auctions, generally speaking?

There's websites for disposition of company assets when they go under. The Makani auction was advertised on the Silicon Valley Disposition website [0] for a while. [0] https://svdisposition.com/

This site is fascinating, thanks!

Re: Makani source code released

#89

Post by jlam »

jefftk wrote: post #9

Blog post from February when Alphabet withdrew funding: https://blog.x.company/a-long-and-windy-road-f8e09d02c9e1 (Disclosure: I work for Google)

To be accurate, partner Shell choose not to re-up its investment after exactly one year, from 2019 Feb 12 to 2020 Feb 18 as indicated in the blog post you linked (actually https://link.medium.com/KBxNNZGcK9 since your link didn’t work for me). It seems unfair to blame Alphabet solely, or even Larry, as one comment below did.

Re: Makani source code released

#90

Post by yourapostasy »

tinco wrote: post #84
tobinfricke wrote: post #64

Earlier quoted context omitted.

While our code might be too specialized to help out other crosswind kite power companies in particular, I think the technical document might be quite impactful: https://storage.googleapis.com/x-prod.appspot.com/files/Maka... The chapter "Airborne Wind Turbine Performance" contains some sobering lessons for the field and deserves a close read.

Thank you so much for that document it's so interesting. Interesting lesson from the exec summary: The real world kite underperformed the model by nearly half, and from the numericals it seems like the main reasons we're that the turning radius was about double that what you were trying to get, and that the tether drag was a significant loss that was not accounted for. The next gen model would be the same span but wi…

> ...tether drag was a significant loss that was not accounted for...

I wonder if some of the losses to tether drag could be made up for by re-purposing some of the wave energy tech to capture energy from the base of the tether as the kite pulls and slackens on the base, or if the tether could be made rigid on demand with some tech in the future.

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