Generate Electricity With A Candle

What you see above is a generator that converts heat to electricity. [Reukpower’s] thermoelectric lamp is one of those hacks that makes you scratch your head even though you understand why it should work. The heart of the system uses a Peltier cool, just like the thermoelectric solar generator. When there is a temperature differential from one side of the Peltier to the other a small current is generated.

In this case a candle heats one side and a heat sink cools the other. The tiny voltage picked up from the Peltier’s contacts is then boosted using a joule thief. We’ve seen LEDs powered with a joule thief before, benefiting from their own low power consumption. In this case, the boost circuit is scavenged from an emergency phone charger and probably achieves higher efficiency than if he had built it himself.

Autonomous Bassline Generator

[youtube=http://www.youtube.com/watch?v=dcqpxd0O6Mw]

We’ve been watching this project ever since [Dann] emailed us about the first prototype back in September. This bassline generator has a lot of functions we like, such as an adjustable melody seed, light-sensitive controls, and device interactivity. Line up a row of them and they’ll sync up the beat, building layers of sound on top of each other (see the first video after the break).

The system is built around an ATtiny84, putting its pulse width modulation channels to work for sound generation. [Dann] has some kits available but he’s also posted everything – the schematics, PCB layout, and code – if you want to throw one together on a breadboard.

Continue reading “Autonomous Bassline Generator”

William Kamkwamba Talks Windmills With Jon Stewart

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.

Power Generating Backpack

[youtube=http://www.youtube.com/watch?v=UL_CUbN9F7E]

In the military, you have to carry tons of stuff. This is something we hear and see all the time. They are always trying to come up with ways to reduce the weight or quantity of the things that you bring into the field. This power generating backpack harnesses the natural up and down motion of your steps to produce power. This could reduce the amount of batteries carried into the field greatly. That’s what they say anyway, how many batteries do soldiers normally carry around? Aside from that point, we think it is pretty cool. We could see using this to keep our cell phone or GPS charged on long hiking and camping trips. You could also build something of your own to work similarly.

12kW Solar Collector

[youtube=http://www.youtube.com/watch?v=jTvAL7ty53M]

Though not much info is readly available about it on the web, [Joe Carruth] is trying to build publicity (and venture capital) for his home-built solar electric generator. At its essence, it is a Stirling dish system with an adjustable composite mirror surface. This means that instead of having to rotate the entire contraption in order to follow the Sun, [Joe] only has to make  the mirror segments pivot. A Stirling steam engine at the tip converts the energy into the movement used to generate electricity. Solar power plants (or ‘farms’) that are emerging are beginning to consider the advantages of using more efficient Stirling dishes rather than less efficient solar panels. If anyone has an idea as to how [Joe] can automate sun tracking for the mirrors, please post it in the comments. A couple more videos on the topic (in general) are available below: Continue reading “12kW Solar Collector”

Tape Measure Generator

generator

[Dr. West] wanted to do his small part to help save the planet. He has built a small generator from a stepper motor and a tape measure. The tape part of the tape measure was replaced with some cord. The spring loading mechanism makes the string re-wind automatically, which is nice. He shows it attached to one leg, with the string tied to the other, generating power while he walks.  This is cumbersome, but seems fairly effective. You can see him waking around in a video after the break. Would this benefit from a flywheel or friction drive to keep the motor spinning after each pull?  How can he rig it to feed off of the motion of only one leg to avoid tripping hazards?

Continue reading “Tape Measure Generator”

Washing Machine Generator

stator

Building a generator can be a fun and fairly simple project. Getting a large DC motor however can sometimes be difficult. Here is a writeup on how to make a generator from an old washing machine drive. It looks like you might need to find a specific machine called the “Smart Drive” to follow their directions exactly though. If you happen to find one, or know of a unit with a similar motor, you can follow these directions to end up with a fairly decent wind powered generator.

[thanks TripleB]