'Windmill': China tests world’s first megawatt-level airship to capture high winds

As a European... Are feet logarithmic? Wouldn't even surprise me that much.

The zero key got stuck.

They used different people's feet.

So that "10,000 meters" didn't scale right, clearly. But you also can't possibly call those "high altitudes". Small planes like cessnas fly at low altitudes, like 2,000 - 5000 ft, a 747 flys at a high altitude, 40,000 ft; 1600 ft is nothing, that's lower than some buildings.

Fossil fuels are from shit the dinos ate, like plants and other dumb crap. The belief that coal-rollers are cool enough to burn liquid dinosaurs is easily the single biggest lie of the oil industry.

Closely followed by -gestures wildly-

And Africa, and South America, and the middle east, and Europe. Don't pretend the rest of the world isn't still burning fossil fuels it's not just the US

Meanwhile in the US, rich assholes are firmly convinced coal and oil are the future.

God I hate this place.

An untethered AWE cannot produce any power

Also, it looks cool as fuck!

...produces H2?

Switching to renewables makes a lot of sense from an economic and ecologic point of view but also geostrategically. Unfortunately, Western governments have pretty much lost the ability to act on those considerations. This is due to then being beholden to a few billionaires who would rather see civilisation as we know it end than accept a few percentage points revenue drop for a couple of quarters.

They aren’t limited by democracy.

The article says:

The S1500 features a main airfoil and an annular wing that together form a giant duct. Inside this duct are 12 turbine-generator sets, each rated at 100 kW.

That suggests to me (admittedly a layman) that each blimp is more like 1.2MW?

Would it be possible to use heat to get it to float, instead of helium? Heat it up with electricity.

Sure, that would be possible. The generators themselves will produce some amount of heat. It's also going to have a fair amount of passive lift, as it's essentially a kite. So simply being able to maintain a rigid shape and effective airfoil could do a lot to produce the desired lift. If it were redesigned with that in mind, shaped more like a glider/kite/parasail, something to maximize lift, it's possible that it could be done without a light gas, though it would also be more reliant on favorable winds.

I have to wonder though, how much the power transmission lines weigh, that seems like a serious limiting factor on maximum attainable altitude.

The transmission line question is interesting though, there's a complex optimization problem there. Traditionally with wind, larger turbines are more efficient. As you increase the turbine blade size, the area that the blades cover (and thus power generation potential) increases more than the mass of the blades do. So the result is (generally speaking) a larger wind turbine is more efficient than a smaller one. But now factor in the transmission line... The larger the turbine the more power it generates AND the thicker (and heavier) the transmission line has to be for its entire length. To complicate things more, higher altitudes mean stronger and more reliable wind. So now how do you optimize for turbine size/cable gauge, and cable length/altitude?

It seems tricky, but like perhaps there's just a right answer, an optimal size.

it is 1.2mw = 12x100kw

Using hot air instead of helium would not work. The density of hot air is much higher than helium, so you would need a significantly larger airship to lift the same mass of payload (the useful bits). That and keeping the air hot would require constant energy input reducing the efficiency of the system dramatically. I'm pretty sure that system would be literally impossible to construct.

[face Palm].

JFC people, take a grade 10 physics class.

            a
           l
          a
         l
        a
       l
      a
     l
    h
   a
  B

Yes but, you see, that was an animated film aka a work of fiction. This is happening in reality.

Kinda.

Promising concept too, but this is 250-500x the scale of that.

That looks complicated and frankly kind of stupid. Imagine trying to get something like that working without having an engineer standing by that can get everything fixed once it crashes down or something else like that happens.

Maybe there's energy intensive processes that they could do up there instead. Something like Haber Bosch. Then bring the products down.

Maybe over estimate temperature deratings and maybe add a new wind speed thermal pulling capacity. But more likely forgo European and NA electrical standards entirely and submit questionables value for CE approval.

They should do a Nikola Tesla and transmit electricity wirelessly

Yes the Hindenburg disaster had more to do with the flammable paint used than the hydrogen inside it. But the safety procedures when working with on the ground may be more expensive than just using helium.

Hydrogen is hard to contains long term, it leaks through most materials. I'm no expert on the matter but I suspect the gains in lift would be partly negated by the changes to the envelope of the container.

I'm no scientist but I think it would take an absurd and unrealistic amount of these to have any sort of noticeable effect on average wind speeds.

Enough wind redirection could affect weather patterns. But we won't run out of wind, spoiler but wind power is just indirect solar power.

Typically wind is dissipated by friction losses with the surface I think (bleeding off speed and energy by making waves, waving trees, and just rubbing against the ground) and wind is generated by heat from the sun (warm air expanding pushing against cold air, creating pressure differentials across thousands of miles).

Because wind is quick to regenerate and this does nothing to stop that the result is probably a pretty small drop in average wind speeds around the new mill and no greater ramifications than slightly less pollen travel in the spring.

The windmills will steal all the spinning from hurricanes, a bust to home owners insurance

While it is rather complex and hard to predict, the most likely global outcomes are fewer extreme weather events and extremely mild cooling. The hairy ball theorem tells us there's already somewhere on the globe with no wind, so it's not that big of a deal to convert some wind into electricity. This particular approach couldn't convert "all" wind into electricity.

https://www.sciencenewstoday.org/spinning-skies-how-earths-rotation-shapes-our-weather -- We won't run out of wind until after we start slowing down the rotation of the earth, and we watch that pretty closely to know when to add leap seconds, and I imagine it's an just absolutely huge store of energy in the form of angular momentum (et. al.).

In theory nothing. Wind is just the flow of air from high pressure to low, which itself is caused by heating from sunlight. If uncollected, the kinetic energy of the wind would eventually be lost as heat to friction between air molecules.

It will impact weather patterns and severity. I’ve certainly not done the work on how much, nor do I really have a grasp on the scales involved, so that’s mostly a meaningless statement, but I can say with confidence the impact will be real. Just like dams affecting rivers, icecap mass affecting heat reflection, and solar panels increasing local temperatures.

Given that one of the impacts of global climate change has been increased weather severity and chaos, I am not afraid of positing that reducing the severity and chaos of the jet streams could be a good thing.

Similarly, there are some interesting projects going on surrounding the use of aerogel and other materials that could help focus sunlight at the top of the oceans, where evaporation can actually occur, that are focused on creating clean drinking water—and while I think this is a good end unto itself, a nice side benefit would be less solar energy reaching the ocean and raising the body temperature.

For once, it’s cool to hear about proposed industrial projects and their side effects and they’re maybe positive, instead of “well that sounds like it’s going to leech heavy metals into the surrounding community”

Of course, aerogel is horrible to work with and clogs if it doesn’t break, and nobody else has solved the problem of scaling up and dealing with the steam getting in the way. On the lightweight flying jet stream turbine front, well, I’ve been following development for 8 years and nobody has even solved the ‘limited supply of helium leaking away into space’ problem for starters. And it’s hard making an efficient generator so lightweight that it can fly. So we don’t have to worry about them potentially improving global weather severity just yet. Or potentially devastating our remaining populations of migratory birds!

I feel like this should be an xkcd explains (if it isn't already one)

Things get more violent. Wind tries to find the path of least resistance, though as a fluid, so it's taking all paths in proportion to how much resistance it has (just like electricity). If you increase the absolute resistance in one area, it reduces the relative resistance everywhere else, so you end up with increased airflow everywhere else and a reduction where you added resistance. Which means more wind outside of the turbine's path (because it's going to equalize that pressure differential one way or another). More flow through the same volume means higher speeds and forces (think like turning up the pressure on a tap).

But wind turbines don't have a constant effect on wind resistance; it depends on how fast it's spinning or how fast the wind is moving. When the wind slows, the resistance goes down, and when resistance goes down, wind speed increases. So you end up with an oscillating effect where the wind goes through cycles of strengthening, losing more energy to the turbines and weakening, which means the turbines take less energy, and the winds strengthen again. Though you'd need to be taking a significant amount of that energy to see an extreme effect like this.

Apparently taking more than 53.9% of the total wind energy in an area is enough to slow the wind to a stop (again, a violent, turbulent, oscillating stop, not a gentle end of wind).

I feel like all the responses you're getting are probably generally correct in the context of wind at/near ground level. But I feel like sticking a bunch of these in a JET STREAM is (maybe?) an entirely different matter. Or at least it could be, and I too am curious what the potential ramifications are.

Jet stream winds are not just wind like any other, are they? Various jet streams have serious impacts on weather. If they harnessed and substantively bled off the Pacific jet stream, are there potentially grave consequences on the already variable El Niño and La Niña oscillation? If it could cause serious shifts in the weather, that would affect the livability of areas, create more dangerous weather conditions, and impact farming way around the globe from their wind farm installation.

Maybe none of these are genuine scientific concerns, but frankly I don't trust China to do the science for the rest of us. Pretending these are genuine concerns, say they screw something up - it probably doesn't too seriously impact Chinese weather as they harness the jet stream winds right at the point where it leaves their airspace. But the ramifications for the rest of the world could then be dire, and I'm not sure that is remotely a concern for them. Could be an economic advantage even. Two birds, one stone.

Its cubic actually

https://thundersaidenergy.com/downloads/wind-power-impacts-of-larger-turbines/

I don't understand the physics, but every model of power output from wind turbines uses V^3 for the formula

Increasing the speed increases both the kinetic energy of the wind hitting the turbines and the amount of wind that hits the turbines each second.

It has to do with type of turbine that uses "airfoil principle". Your formula works for "cup"/Parachute design, but airfoils/upwind sails are "magic"

We don't directly harvest the kinetic energy. That increase probably has to do with how the wind provides lift to the blades. Of course, you couldn't keep increasing like that until the harvested energy is greater than the kinetic energy. But I'm sure at any wind speed we only get a tiny fraction.

I'm out of practice with my physics so apologies if this is a n00b question, but:

I'm unclear what (rho V) is and how you converted to that from mass (m). Further unclear what (rho A d) refers to.

Can you explain / link to an explainer on this?

TIL thanks for bringing this up

You don't need to, but your life will have been without purpose if you don't see it. Kidding, but I did see it for the first time last year, and it was pretty good

Wouldn't the heavy transmission line itself act as the anchor like the chain on a cruise ship?

They did mention 30% cost savings. (these claims are easy to exaggerate though) While already useful scale, the advantages would grow with higher scale and high volume automated production.

Article says wind speeds are môre steady up there, wouldn't that mean whatever you put up there is build to withstand those winds?

A wind turbine automatically feathers. Why can't the airship automatically raise and lower itself?

With modern forecasting, getting it's height right shouldn't be too hard?

It's a Zeppelin. 100 year old tech.

Tether to the ground limits X-axis. Buoyancy limits Y-axis. Draw a circle around the sine of ground-to-windmill hypotenuse and you immediately know the max constraints of where the windmill will be

It did that already, yes. It's a BFB: Big Friendly Blimp

Birds don't fly at 3,000 feet.

They'll hire Anna Paquin, she'll sort something out.

Air traffic has to adapt.

Paint the balloons red and put lights on them so aircraft don't hit them.

This is intended as emergency power relief not a full time energy source.

This one in particular: maybe.
The approach in gerenal: not so much.
Have a look here: https://skysails-power.com/systems/venyo/