Harvesting wind energy from flag flapping

[Bud]

Capturing the wind's energy using "piezoelectric" flags
https://physics.aps.org/articles/v8/s12

Putting this in Dodgy Technology subforum rather than in Renewable one, since it sounds like it.

[pcprogrammer]

Interesting, but how many of these would you need to supply a house with enough energy to run whatever appliances?

And how long will the material last in these conditions?

And are windmills not already invented?

Etcetera, etcetera....

[AndyBeez]

From the title I thought this was some clever (crowd fund harvesting) system using the Karman votices spinning downstream of the flag. See
https://en.m.wikipedia.org/wiki/Karman_vortex_street

Instead, the flag pole alone is likely to collect many megajoules more energy than a piezzo flag, when providing a ground path for a thunder cloud.

[helio0centra@gmail.com]

Interesting, but how many of these would you need to supply a house with enough energy to run whatever appliances?

They'll probably aim lower. Maybe just charge a phone?

[pcprogrammer]

Interesting, but how many of these would you need to supply a house with enough energy to run whatever appliances?

They'll probably aim lower. Maybe just charge a phone?

Wow that is a great idea They can use this in Strasbourg to charge the phones of members of the European parliament

[PlainName]

Interesting, but how many of these would you need to supply a house with enough energy to run whatever appliances?

They'll probably aim lower. Maybe just charge a phone?

Indeed. If it produced any output greater than it takes to collect, surely that's a plus. Not everything has to scale to continent-size consumption.

I don't think this is at all dodgy if it works.

[SiliconWizard]

Maybe we could harvest good energy from all the farting.

[helio0centra@gmail.com]

It might be a novelty item you see in department stores and TV infomercials in a few years: a flag with USB outputs to charge you phone from the wind. But I can't see it ever being as good as a wind turbine or solar panel.

[NiHaoMike]

Reminds me of an idea someone had to use piezoelectric sheets to generate electricity from flowing water, touting that it's "more environmentally friendly" as it doesn't need a dam. I guess it never occurred to him that it would be far more effective to sit a water wheel in the river, still no dam needed!

[Bud]

There was a research document I've seen elsewhere that claimed getting experimental 3mW of energy out of such gizmo , but special conditions were required such as vibration from the flag matching the resonant frequency of the attached piezo converters.

[pcprogrammer]

Maybe we could harvest good energy from all the farting.

Yes put micro turbines in our pants  because most of us only produce smelly wind instead of usable methane.

Another option is to charge our phones when walking, like those self winding watches used to do.

But think of cows, it has been looked into way back already. Actually cow dung from big stables is being used to extract methane from.

And recently there is also some looking into capturing methane from cow burps

It is in Dutch but here is a site about it: https://www.agriwijzer.nl/product/39?name=METHAAN+VERMINDERING+OPVANG+KOEIENBOEREN

Edit: it is not for the actual capture of the methane, it is for health and food efficiency monitoring.

[PlainName]

I can't see it ever being as good as a wind turbine or solar panel.

Sure. But you can't (yet) roll up a solar panel, and they look shit stuck at the top of a flag pole. The thing here is not how much it puts out but that it puts something out where previously there was nothing.

Of course, that assumes the product is still basically a flag, and if it churns out half a microwatt no-one is going to use one. But, you know, maybe see what they produce before rubbishing it.

[AVGresponding]

[tszaboo]

I have to link the old SMBC comics again: