Hi, I'm a third year aerospace engineering student so naturally I was suspicious of this, and the napkin maths looks pretty bad?
In the UK at this moment the price of energy is £0.09112 per kWh:
The WindTree from the video has a unit cost of 50,990€ before tax. Working with GBP for my convenience, that's £44,416.62, or £53,299.94 after VAT.
Their website alleges that it can power 100m^2 of 20kWh/m^2 office space every year. That's 2,000kWh of energy produced per year, per unit.
Neglecting installation and maintenance costs, ignoring tax, and assuming the WindTree achieves this rate of energy production for ten years, that's £44, 416.62 / (10 * 2,000) = £2.22. Over twenty four times as expensive as power on the UK's national grid, produced almost half by renewables. That's really, really bad. And that's also assuming the WindTree is in good operating conditions, which in a city it is not. Compare this to onshore or even offshore floating wind farms (the latter of which have become increasingly economically viable and are out of sight for all the NIMBYs who oppose onshore wind farms) and it's a disaster and extremely wasteful when it comes to sustainable energy production.
Their advertising is bad and nonsensical if you have technical knowledge. Nowhere do they provide performance data for different wind speeds with their turbines, only for rpm. When they advertise being able to operate at very low wind speeds, why do you think they might want to obfuscate how much power they produce at those speeds?
Then you see outright false statements like this:
Which is bullshit, it's not a unique technology. It's a basic Savonius wind turbine, which is also the least efficient of the vertical axis wind turbines because it's literally just two scoops. It was invented in 1922 and patented in 1926. What this company patented was their specific design, the tree-like structure, and the petal-like structure with the solar panels on it (which, don't get me started, the turbines shade those panels in multiple promotional pictures).
"Light and almost without inertia" is a nothingburger statement, and "potentiating the diffuse energies" is so incomprehensible that I genuinely think they asked AI to make some marketing babble up for them.
That +- symbol is really not inspiring confidence, especially when they've cut 65 days off the year already. "capitalises watts to make kilowatts" is also a stupid marketing babble sentence.
I would love to see the study where they proved that their Lorax fake tree with turbines acts like a scarecrow.
Their "datasheets" are hardly even that, mostly filled with marketing babble with the bare minimum of useful information.
They advertise being able to deploy them anywhere, as if that's a huge advantage. It isn't! Deploying one of these in a city is a terrible idea because you'll get far slower wind speeds and worsened illumination of the solar panels throughout the day. You put your energy production facilities in the most optimal location because power losses of transmission are pretty low (average 6% in the UK's national grid) and the costs of losses and infrastructure for transmission are FAR outweighed by the improved efficiency from operating in that location and on that scale. Just plant a tree! It's far better for wildlife in cities, stick a bench under it so people can sit in the shade, and it's more aesthetically pleasing than plastic tree number 503 from The Lorax.
The whole project feels more like a linkedin art piece than anything useful for a green future. These sorts of projects drum up loads of support and then fail to produce anything meaningful, and waste money and resources doing so.