For many of us our landscapes are dotted with wind turbines, the vast majority of which are horizontally aligned as if they were giant aircraft propellers. A much rarer sight is the vertical wind turbine, which remains a staple of the wind power experimenter. [Troy] and his brother have posted a video showing a small wind 3D printed vertical turbine, which unusually includes an alternator made from scratch as well as the rotor itself.
The machine adopts a Savonius rotor design with three scoops, which offers simplicity and high torque at a lower rotational speed than some of the alternatives. The scoops are assembled from a number of 3D-printed sections, and directly drive the generator which uses a large number of coils on a stator encircled by a rotor containing an array of magnets. A simple rectifier and three-terminal regulator produces a 5-volt output.
Sadly there was not enough wind to give it a decent test for the video, but they demonstrate it with a very large fan standing in. We like the alternator design but we’d be interested to see how the sectional rotors hold up in outdoor conditions, and perhaps that regulator could benefit from a switch-mode component. If you fancy a go he says he’ll release the files as open source if there’s enough interest. We’re interested [Troy], please do!
It’s not uncommon to drive around the neighborhood on trash day and see one or two ceiling fans haphazardly strewn onto a pile of garbage bags, ready to be carted off to the town dump. It’s a shame to see something like this go to waste, and [Giesbert Nijhuis] decided he would see what he could do with one. After some painstaking work, he was able to turn a ceiling fan into a wind turbine (of sorts).
While it’s true that some generators and motors can be used interchangeably by reversing the flow of electricity (motors can be used as generators and vice-versa) this isn’t true of ceiling fans. These motors are a type called induction motors which, as a cost saving measure, have no permanent magnets and therefore can’t simply be used as a generator. If you make some modifications to them, though, like rewiring some of the windings and adding permanent magnets around them, you can get around this downside of induction motors.
[Giesbert] does note that this project isn’t a great way to build a generator. Even after making all of the changes needed to get it working, the motor just isn’t as efficient as one that was built with its own set of magnets. For all the work that went into it, it’s not that great of a time investment for a low-quality generator. However, it’s interesting to see the theory behind something like this work at all, even if the end result wasn’t a complete wind turbine. Perhaps if you have an old ceiling fan lying around, you can put it to better use.
It is three weeks after the apocalypse. No zombies yet. But you do need to charge your cell phone. How do you quickly make a wind turbine? If you’ve read this project, you might reach for a few empty water bottles. This educational project might not charge your phone without some extra work, but it does illustrate how to use water bottles to make a workable air scoop for turning a crank and possibly generating electricity.
That takes care of the wind and water aspects, but how did we get solar? According to the post — and we agree it is technically true — wind power is a form of solar power since the wind is driven by temperature differences created by the sun. Technically true!
The wind turbine’s blades look professional but you’ll be surprised to see that they’re simply cut from a PVC pipe. And they work great. The air compressor is taken from a car and the base of the wind turbine’s tower started life as a bed frame. As you’ll see in the video below, the whole setup is quite effective. It would have been nice to see him using his leg mounted, beer bottle propulsion system at the same time, but the air hose may not have been long enough to make good use of them.
There are plenty of places outside where you may like to have a project requiring electricity that may not get enough sun for solar power to be viable. Perhaps wind power could be used instead? [Greg] has a project to create a platform for using a small wind turbine to generate the power for your projects.
The wind turbine that [Greg] designing is a Savonius-style wind turbine that would put out between 5 and 12 volts. In a Savonius turbine, blades are mounted on a vertical axis allowing for a smaller, less complicated build than traditional horizontal axis wind turbines. The design is named for its inventor, Finnish engineer Sigurd Johannes Savonius.
After doing some research, the design will have a 2:1 height to blade ratio and use three pairs of overlapping curved blades stacked on top of each other, each pair offset by 120 degrees. This design, [Greg] figures, will come within a few percentage points of the efficiency of more exotic blade shapes while making the windmill easy to design and implement. Being half cylinders, the blades can easily be made from existing objects cut in half – pop cans, for example, but there has been some designing the blades in Fusion 360 for 3D printing. The stator board has been designed and the initial prototypes of it and the rotor have arrived, so the testing can now commence.
Once the design is finalized and the prototype working, it’d be interesting to see some projects start showing up using wind power instead of solar power. Take a look at this design for a vertical wind turbine, and this design for a simple, straightforward turbine.
What’s great about the Power Generation Modules project headed by [Cole B] is the focus on usability and modularity. The project is a system for powering and charging small devices using any number and combination of generator modules: wind turbine, hand-crank, and water turbine so far. Power management and storage is handled by a separate unit that acts as a battery bank to store the output from up to six generators at once. There’s also a separate LED lamp module, designed to be capable of being powered directly from any of the generator modules if needed.
The hand crank is straightforward in concept, but key to usability was selecting a DC gearmotor with a gear ratio that made cranking by hand both comfortable and sustainable; too weak of a crank and it’s awkward, too hard and it’s tiring. The wind turbine has three compact vanes that turn a central shaft, but testing showed the brushless motor it uses as a generator isn’t a good match for the design; the wind turbine won’t turn well in regular wind conditions. The water turbine prototype showed great success; it consists of an epoxy-glazed, 5 inch diameter 3D printed propeller housed in a section of PVC pipe. The propeller drives a brushless motor which [Cole B] says easily outputs between eight to ten volts when testing in a small stream.
The team has plans for other generators such as solar, but this is a great start to an array of modules that can be used to power and charge small devices while off the grid. We’re happy to see them as a finalist for The Hackaday Prize; they were selected as one of the twenty projects to receive $1000 cash each in the Power Harvesting Challenge. The Human-Computer Interface Challenge is currently underway which seeks innovative ideas about how humans and computers can interface with one another, and twenty of those finalists will also receive $1000 each and be in the running for the Grand Prize of $50,000.
When we think of wind turbines, the first thing that usually comes to mind is the typical Sim City-esque type – 3 blades, gigantic, and wired into the municipal power grid. In truth, the world of wind power generation is far more varied indeed – as [Vittorio]’s vertical-axis wind turbine shows us.
So what exactly is a vertical-axis wind turbine, you ask? Well, rather than the typical setup with blades rotating about a horizontal axis, as in typical utility turbines or a classic electric fan you might use to cool off on a sunny day, instead a vertical axis is used. This necessitates a very different blade design due to the orientation of the rotational axis relative to the flow, so such turbines can be quite visually striking to those unfamiliar with such designs.
[Vittorio]’s design is a great way to get to grips with the type. The blades and supports were initially created out of PVC gutter channel, though 3D printed versions have also been developed. The motion is turned into electricity by using a simple brushed DC motor as a dynamo.