For many of us, our passion for electronics and science originated with curiosity about some device, a computer, radio, or even a car. The subject of this book has just such an origin. However, how many of us made this discovery and pursued this path during times of hunger or outright famine?
That’s the remarkable story of William Kamkwamba that’s told in the book, The Boy Who Harnessed the Wind. Remarkable because it culminates with his building a windmill (more correctly called a wind turbine) that powered lights in his family’s house all by the young age of fifteen. As you’ll see, it’s also the story of an unyielding thirst for knowledge in the face of famine and doubt by others.
Continue reading “Books You Should Read: The Boy Who Harnessed The Wind”
[Niklas Roy] built a windmill-powered music box for his backyard, and it was so awesome all the neighbors wanted to take a picture of it. Someone even liked it so much that he stole [Niklas]’s windmill in the middle of the night. (We kind of don’t blame them, it’s a gorgeously clean build.)
In the past few weeks [Niklas] has been mass-producing 20 windmills for the KIKK Festival 2017 to be held in November in Namur, Belgium. The windmills will operate in a cluster, and all play “Für Elise” when the wind blows. However, each one is driven independently and so the music is asynchronous. Since he was building a bunch anyway, he built a replacement windmill for his backyard, and documented how to do it.
Continue reading “Making Music With The Wind”
Wind Turbines are great, they let us humans harness the energy of the wind. Wind is free and that is good, but spending a ton of money on a wind turbine setup begins to make the idea less appealing. [Ted] has spent many years building low cost wind turbines and this one is not only simple but can be made from mostly found parts.
It’s easy to identify the main rotor hub and blade frame which are made from an old bicycle wheel. The blades are standard aluminum flashing normally used in home construction and are attached directly to the spokes of the bike wheel. Mounted below the bike rim is a permanent magnet motor that acts as a generator. A belt couples the motor to the main rotor and uses the tire-less rim as a pulley.
[Ted] has strapped this beast to the roof of his car to measure how it performs. At 12 mph, he’s getting between 18-20 volts at 2 amps. Not too bad! Bikes and bike parts are cheap (or free) and there is no surprise that they have been used in wind turbine projects before, like this one that hangs from a kite.
When [brokengun] decided to build a 7 ft diameter wind turbine, he had no idea how to even start, so he did as most of us would do and read some books on the topic. His design criteria was that it would be simple to construct and use as many recycled parts as possible. This wind turbine charges a 12 volt battery which can then be used to power a variety of gadgets.
Although made from recycled components, this isn’t a thrown together wind turbine. A lot of thought went into the design and build. [brokengun] discusses matching the blade size to that of the generator in order to maximize power and efficiency. The design also incorporates a feature that will turn the turbine perpendicular to the wind if the wind-speed gets to high. Doing this prevents the turbine from being damaged by strong gusts.
For the main support/hub assembly, a Volvo 340 strut was used because they are widely available, cheap and known for being long-lasting. The tail boom is made from electrical conduit and it’s length is determined by the size of the main fan rotor. The tail vane is made from steel sheet metal and its surface area is also dependent on the fan rotor size to ensure that the turbine functions properly. The blades are made from wood but instead of making them himself, [brokengun] felt these were worth ponying up some cash. [brokengun] also scored a 30 ft high lattice tower an airport was getting rid of. This worked out great as it’s just the right height for a turbine of this size.
Continue reading “7-Foot DIY Wind Turbine Proves Size Matters”
Green hacks implement one of two philosophies. The first is über-technical, with very expensive, high-quality components. The other side of this coin creates green power out of junk. [Timot] obviously took the latter choice, building a windmill out of an old washing machine motor and a few bits of PVC.
The generator for the windmill is based on a Fisher and Paykel direct drive usually found in clothes washing machines, rewired to provide 12 Volts at low RPM. At high speeds, the generator can produce 80 Volts, so a charge controller – even one based on a 555 chip – was an excellent addition.
For the other miscellaneous mechanical parts of the build, [Timot] cut the blades of the windmill out of 200 mm PVC pipe and sanded them down a bit for a better aerodynamic profile. With a custom fiberglass spinner, [Timot] whipped up a very attractive power station that is able to provide about 20 watts in normal conditions and 600 watts when it’s very windy. Not enough to power a house by any means, but more than enough to charge a cellphone or run a laptop for a few hours out in the back country.
[Niklas Roy] is at it again. He’s applying wind power to his projects by using umbrellas. He was inspired by the shape of an anemometer, and umbrellas turned out to be a great choice because they’re cheap and easy to find.
Anemometers measure wind speed by capturing it with egg-shaped sails (in fact, we’ve seen them built from plastic Easter eggs before). The umbrellas have a much larger area and will capture more wind. Still it’s a big jump from measuring wind speed to generating energy. That’s why he’s not trying to generate electricity, but instead using the mechanical force directly. He took a page from one of last year’s projects and used the dual umbrella setup to power a music box, thereby reinventing the wind chime. The triple-umbrella unit seen above serves as a bubble machine, driving a series of plastic rings through a soapy solution and letting the wind do the rest. We’ve embedded his demo video after the break.
Continue reading “Umbrella-based Windmills”
Last night [Jon Stewart] interviewed [William Kamkwamba] on The Daily Show. [William] is the young man from Malawi who at the age of 14 built a windmill generator out of discarded items. Now at 22 years old, [William] is working on his SAT scores in hopes that he can attend college in the US. We get a bit more insight about him and his build as he promotes his new book.
[William] was 14 when he completed the three month long build of his generator. He had previously dropped out of school because “my country was experiencing some famine”. The only resource he had at his disposal was a library that is funded by the US government (sounds like that turned out to be a good investment!).
After seeing a photograph of a windmill he was driven to succeed by the mantra: “somewhere somebody did it, it didn’t fall from the sky”. He goes on to explain how he built a circuit breaker (pictured above) to prevent a short circuit from burning his house down. Two nails are wrapped in wire with a magnet in the middle. If there is a short circuit, one of the nails will repel the magnet while the other attracts it. The nail is connect to a switch and when it moves to one side the switch is opened, breaking the circuit. Upon hearing this, [Stewart] makes the obvious comparison between [Macgyver] and [Kamkwamba].
One of the most endearing points in the interview is a story [William] shares about his first experience with the Internet. He was invited to the TED conference in 2007 and someone asked him if he’d used the Internet. Of course he hadn’t and they then started talking about using Google. When the search engine was explained to him he suggested that “windmill” be entered as a query. When millions of hits were returned his revelation was “Where was this Google all this time?”.
This is an amazing story that we can’t get enough of here at Hack a Day. Make sure you don’t miss the interview which starts 12:25 into the episode.