Flying kites deliver container-sized power generation • Hacker News Board

Re: Flying kites deliver container-sized power generation

#61

Post by Scea91 » Thu, Jan 18, 2024, 7:28 PM UTC

Interestingly, the very first statement is quite misleading. The statement:

> On average, a humble wind turbine uses less land area per megawatt-hour than almost any other power source.

The article itself refers to this citation [1]. It says, unsurprisingly, that the most land efficient power source is nuclear. The statement is of course technically true because it says "almost any power source".

With wind, however, even that is tricky because you can either count just the area directly below the turbine body, which is still higher than nuclear and unreasonably optimistic because you severely limit a far bigger area. If you count also the spacing (too pessimistic on the other hand because part of the land might be used for farming) then wind farms range across the whole scale of land efficiency.

I think its fair to say that land use of wind farms is "complicated", but saying its almost the best in this regard sounds like manipulation.

[1] https://ourworldindata.org/land-use-per-energy-source

Re: Flying kites deliver container-sized power generation

#62

Post by dukeofdoom » Thu, Jan 18, 2024, 7:29 PM UTC

why not a blimp?

Come to think of it, I'm kind of curious why a RC blimps have never become popular. I own DJI drones. But no blimps.

Re: Flying kites deliver container-sized power generation

#63

Post by IanCal » Thu, Jan 18, 2024, 7:30 PM UTC

NullPrefix wrote: post #58

nirolo wrote: post #48

There's been a recent video by the German "Sendung mit der Maus" (basically how does stuff work for little children) about these kind of generators. I did not double check if the company in the video is the German one mentioned in the article, but chances are high. Video and subs are in German only, but it's less than 10 minutes and one can see a little how it works. https://m.youtube.com/watch?v=aqfFZDWiJOI

Why are these people wearing safety helmets? Does this imply that everyone living under the kites will have to wear one too?

They're under a crane lifting stuff up overhead on a work site, that's probably why.

Re: Flying kites deliver container-sized power generation

#64

Post by qnsoaejacniln » Thu, Jan 18, 2024, 7:32 PM UTC

tamimio wrote: post #60

qnsoaejacniln wrote: post #53

Earlier quoted context omitted.

Just wondering, how were you communicating to the airplanes in vicinity? Radio would require the planes to be listening on a specific frequency and ADSB Out would require the planes to have ADSB In which is not guaranteed.

It wasn’t an ADS-B, Transport Canada (the FAA equivalent in Canada) doesn’t like ADS-B on drones yet, so the solution was to have an SDR (BladeRF, full-duplex for Tx/Rx), the on-board SBC had a server the received the voice sample (either direct through ground station MIC or automated reading directions, alt, etc every X period of time) and then broadcasting it to the airband, so it’s simply: Ground station mic -> in…

Super cool!

Re: Flying kites deliver container-sized power generation

#65

Post by NullPrefix » Thu, Jan 18, 2024, 7:33 PM UTC

IanCal wrote: post #63

NullPrefix wrote: post #58

Earlier quoted context omitted.

Why are these people wearing safety helmets? Does this imply that everyone living under the kites will have to wear one too?

They're under a crane lifting stuff up overhead on a work site, that's probably why.

but it's not a construction site though

Re: Flying kites deliver container-sized power generation

#66

Post by jrockway » Thu, Jan 18, 2024, 7:34 PM UTC

Interesting! I always try to guess how these things work before I read the article. My imaginary design would have the kite pull a heavy weight up and as the weight moves, it rotates a generator. When the weight reaches the end of the travel, it falls back down and the cycle repeats. The flaw with this design is if the wind was strong enough to pull the weight up, then the weight is not going to be able to fall back under its own power. That's why the real design just uses a motor to do that. Makes sense!

Re: Flying kites deliver container-sized power generation

#67

Post by sambazi » Thu, Jan 18, 2024, 7:37 PM UTC

NullPrefix wrote: post #58

nirolo wrote: post #48

There's been a recent video by the German "Sendung mit der Maus" (basically how does stuff work for little children) about these kind of generators. I did not double check if the company in the video is the German one mentioned in the article, but chances are high. Video and subs are in German only, but it's less than 10 minutes and one can see a little how it works. https://m.youtube.com/watch?v=aqfFZDWiJOI

Why are these people wearing safety helmets? Does this imply that everyone living under the kites will have to wear one too?

no, it's because the are directly at the site where the kite is launched (and on national tv)

Re: Flying kites deliver container-sized power generation

#68

Post by 6gvONxR4sf7o » Thu, Jan 18, 2024, 7:38 PM UTC

I used to work on this at a different company, and I'm glad to see work on it continuing! It's one of those things where the physics works out really great for fantastic power generation, but the engineering is just so damned complex, so it's tough to... get off the ground.

Re: Flying kites deliver container-sized power generation

#69

Post by londons_explore » Thu, Jan 18, 2024, 7:39 PM UTC

Scea91 wrote: post #61

Interestingly, the very first statement is quite misleading. The statement: > On average, a humble wind turbine uses less land area per megawatt-hour than almost any other power source. The article itself refers to this citation [1]. It says, unsurprisingly, that the most land efficient power source is nuclear. The statement is of course technically true because it says "almost any power source". With wind, however,…

Wind turbines can be built big enough that the blades, at the lowest point, are higher than almost all other land uses, except perhaps forestry.

To be honest, the access roads are probably the biggest real impediment to using the land around a wind turbine. Can't exactly farm millions of acres of corn with robotic combine harvesters with a criss-cross of access roads to the base of every turbine.

Re: Flying kites deliver container-sized power generation

#70

Post by Vvector » Thu, Jan 18, 2024, 7:46 PM UTC

shkkmo wrote: post #43

Vvector wrote: post #22

People cannot be anywhere in the radius of the kite cable. Kinda limits where is can be deployed. But the quick deployment could work for some situations.

This is not correct. Untrained people can't be inside the flight zone while operating. This is roughly the downwind quarter of the potential flight zone.

Even a quarter is a huge area. Using the "safety buffer" radius of 425m, that is 560k m2 or 140 acres. A quarter of that is 35 acres, for 30 kW.

For regular wind turbines, it's 30-70 acres per MW generated. That is 20x-40x more power for the same land area. And almost all the land under a wind turbine is freely usable.