Dutch commercial @RTLnieuws hypes rooftop wind turbines once more. Presents this as a new invention by a Dutch entrepreneur (although you can order it on a Chinese website too), claims it produces 1,000 kWh/year, suggests that has been fact-checked by @MilieuCentraal (not). https://twitter.com/jwvdgroep/status/1263823519038799873

Left: text box, suggesting that both the production of this Airturb and of solar panels have been checked with govt sponsored information site @Milieucentraal.
Right: follow that link, and you’ll find out that it only has the solar production number.

This is a recurring theme in the media: “Oh look, something new, did you know that these cute little rooftop wind turbines compare pretty well with solar panels?”
Never a snippet of proof; if you dive into it, no data to support it. Estimates of output often hilariously high.

I can’t understand why @UtrechtUni professor Gert Jan Kramer isn’t critical about this. “Yes, you see those in new housing districts now; we need everything”. Except fake solutions, I’d add. Airturd might be a better name for those.

And I agree with @JWvdGroep that there is some similarity between the ‘new Dutch invention’ (left, €2,500-3,000) and the one he found @AliExpress_EN (right, €453).

The one from AliExpress has a nominal power of 600 W, which is achieved at a wind speed of 13 m/s. That’s 47 km/h, and is hardly ever reached so close to a rooftop (and in the city). A more typical wind speed is probably a few m/s.

At such a wind speed, the turbine will rotate (as the proud buyer in the @rtlnieuws item noted). But it will hardly produce any electricity. Wind turbine output is proportional to the cube of the wind speed, so at 3.25 m/s this one would do 1/64 of 600W. That’s around 9 Watts.