Bad Experiences With A Cheap Wind Turbine

If you’ve got a property with some outdoor space and plenty of wind, you might consider throwing up a windmill to generate some electricity. Indeed, [The Broject List] did just that. Only, his experience was a negative one, having purchased a cheap windmill online. He’s warning off others from suffering the same way by explaining what was so bad about the product he bought.

The windmill in question was described as a “VEVOR Windturbine”, which set him back around 100 euros, and claimed to be capable of producing 600 watts at 12 volts. He starts by showing how similar turbines pop up for sale all over the Internet, with wildly inflated specs that have no relation to reality. Some sellers even charge over 500 euros for the same basic device.

He then demonstrates the turbine operating at wind speeds of approximately 50 km/h. The output is dismal, a finding also shared by a number of other YouTube channels out there. Examining the construction of the wind turbine’s actual generator, he determines that it’s nowhere near capable of generating 600 watts. He notes the poorly-manufactured rotor and aluminium coils as particular disappointments. He concludes it could maybe generate 5 watts at most.

Sadly, it’s easy to fall into this trap when buying online. That’s where it pays to do your research before laying down your hard-earned cash. Continue reading “Bad Experiences With A Cheap Wind Turbine”

Airloom’s Whacky Wind Clothesline Turbine Idea

What if you don’t put airfoils on a central, spinning axis, but instead have them careen around a circular track? If you’re a company called Airloom, you’d say that it’s a very cheap, very efficient and highly desirable way to install wind-based generators that can do away with those unsightly and massive 100+ meter tall wind turbines, whether on- or offshore. Although grand claims are made, and venture capital firms have poured in some money, hard data is tough to find on their exact design, or the operating details of their one and only claimed kW-level prototype.

Transpower's 'flying clothesline' wind turbine setup.
Transpower’s ‘flying clothesline’ wind turbine setup.

Despite the claims made by Airloom, they’re not the first to have this idea, with Transpower in the 1980s making itself famous with their ‘flying clothesline’ that featured a continuous loop of sails tensioned between two ropes. These ran around a pole on either end with each having a generator for a claimed total of 200 kW. Ultimately Transpower seems to have gone under along with many other wind power pioneers of the era as they couldn’t make their idea economically feasible. Something which is a definite trend in the field.

Some parts about Airloom’s design are definitely concerning, with the available images showing each airfoil running along a central rail on a number of wheels and with their ‘Power Takeoff’ (i.e. generator) not defined in any meaningful manner. Here is where [Robert Murray-Smith] had a bit of fun in a recent video, creating his own dual-chain version that somewhat resembles a mixture between the Transpower and Airloom designs. He also put the design up on Thingiverse for others to 3D print and tinker with, requiring a handful of bearings for smooth running.

For the power takeoff, [Robert] suggests that in his design the cogs around which the chain moves could be attached to a generator (like in the Transpower design), but he could see no indication of how Airloom intends to do this. Feel free to put your own speculations in the comments. And if you’re from Airloom, show us the details!

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Hackaday Prize 2023: A 3D Printed Vertical Wind Turbine

We feature a lot of off-grid power projects here at Hackaday, whether they’re a micropower harvester or something to power a whole house. Somewhere in the middle lies [esposcar90]’s 3D-printed vertical wind turbine, which it is claimed can deliver 100 watts from its diminutive tabletop package.

It’s designed to be part of a package with another turbine but makes a very acceptable stand-alone generator. The arms have large scoop-like 3D-printed vanes and drive a vertical shaft up the centre of the machine. This drives a set of satellite gears connected to a pair of DC permanent magnet motors, which do the work of generating. For different wind situations, there are even some differing STL gear choices to speed up the motors. The motors are 12V devices, so we’re guessing the output voltage will be in that ballpark. However, it’s not made entirely clear in the write-up.

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Converting Wind To Electricity Or: The Doubly-Fed Induction Generator

Humanity has been harvesting energy from the wind for centuries. The practice goes back at least to 8th century Persia where the first known historical records of windmills came, but likely extends even further back than that. Compared to the vast history of using wind energy directly to do things like mill grain, pump water, saw wood, or produce fabrics, the production of electricity is still relatively new. Despite that, there are some intriguing ways of using wind to produce electricity. Due to the unpredictable nature of wind from moment to moment, using it to turn a large grid-tied generator is not as straightforward as it might seem. Let’s take a look at four types of wind turbine configurations and how each deal with sudden changes in wind speeds. Continue reading “Converting Wind To Electricity Or: The Doubly-Fed Induction Generator”

How Simple Can A Wind Generator Get?

As the world has moved towards sustainable energy sources over the last few years, it’s increasingly common to be close to a wind turbine. The huge turbines visible on the horizon from where this is being written are the upper end of the scale though, and along comes [Robert Murray Smith] with the opposite, probably the simplest and smallest wind turbine we’ve seen.

His use of a 3-phase motor from a CD-ROM drive as the generator isn’t particularly unexpected, these motors are ubiquitous and readily generate power when spun up. A simple 3-phase rectifier and a capacitor delivers a DC voltage that while the ready availability of switching converter modules should be relatively easy to turn into something more useful.

The clever part of this hack lies then in the rotor, it’s not the propeller-style bladed affair you might expect. Instead he takes a CD, as it’s the obvious thing to fit on a CD motor, and glues a piece of Tyvek on top of it. This is cut to form four flaps which make a rudimentary but effective turbine when the wind comes from the side. It’s beautifully simple, and we wish we’d thought of it ourselves. The whole thing is in the video below the break, so take a look.

Maybe this won’t solve the green energy requirement on its own, but we’ve shown you far larger fabric turbines in the past.

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Scratch Built Wind Turbine Makes Power And Turns Heads

If you’ve ever aspired to live off the grid, then it’s likely that one of the first things you considered was how to power all of your electrical necessities, and also where to uh… well we’ll stick to the electrical necessities. Depending on your location, you might focus on hydroelectric power, solar power, or even a wind turbine. Or, if you’re [Kris Harbor], all three. In the video below the break, we get to watch [Kris] as he masterfully rebuilds his wind turbine from scratch and reconfigures his charging solution to match.

The Rotors Are Built With a 3d Printed Rotor Jig

A true hacker at heart, [Kris] has used a everything from 3d printing to broken car parts in order to build his new wind turbine. The three phase generator is constructed from scratch.  A hand wound stator is held firmly between two magnetic rotors, where 3d printed jigs hold the magnets in place.

A CNC cut backing plate holds everything together while also supporting the automatically furling vane that keeps the entire turbine from self destructing in inclement weather. A damaged wheel hub from [Kris]’ Land Rover provides the basis for a bearing so that the entire turbine can turn to face the wind, and various machined parts round out the build. The only things we didn’t see in the build were hot glue and zip ties, but we remain hopeful. Continue reading “Scratch Built Wind Turbine Makes Power And Turns Heads”

Leading Edge Erosion: When Precipitation Destroys Wind Turbine Blades

Erosion is all around us, from the meandering course of rivers and other waterways, to the gradual carving out of channels in even the toughest mountains, and the softening of features in statues. Yet generally we expect erosion from precipitation to be gradual and gentle, taking decades to make a noticeable difference. This of course takes into account gentle flows and the soft pitter-patter of rain on stone, not turbine blades passing through the air at many times the terminal velocity of rain drops of up to 9 m/s.

As wind turbines have increased in size and diameter of their blades, this has noticeably increased the speed of especially the blade tips. With more and more wind turbine blade tips now exceeding speeds of 100 m/s, this has also meant a significant increase in the impact of rain drops, hail and other particulates on the lifespan of these turbine blades. As comparison, 100 m/s is 360 km/h (224 mph), which is only slightly slower than the top speed of a Formula 1 car.

The effect of turbine blade leading edge erosion (LEE) not only decreases aerodynamic efficiency, but also invites premature failure. Over the past years, special coatings and leading edge tapes have been developed that act as sacrificial surfaces, but as wind turbines only keep getting larger, so does the effect of LEE. Beyond simply replacing LE tape every year on every turbine, what other options are there?

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