green hacks

850 Articles

Growing Algae With An Arduino

October 2, 2009 by 58 Comments

algae_grow

We’ve seen automated grow boxes of all shapes and sizes, but all were for growing plants. [Jared] over at Inventgeek wanted to do something similar for his algae. He started off with an Arduino-based solution that allows the controlled pulse of LEDs connected to his standard bioreactor as a prototype. Once he determined his proof of concept worked, he began work on a design based on the Arduino Pro Mini that has more advanced features such as temperature monitoring and algae culture density monitoring via some fancy IR voodoo. The code is open source and the hardware is easily obtainable, all that remains is the desire to grow algae.

Hacker Rewarded For Creating Electricity

October 2, 2009 by 60 Comments

diy_windmill

[garhol] tipped us off about a self-taught hacker who brought a little light to his tiny home. [William Kamkwamba] dropped out of school because his family lacked the $80 per year for tuition. At the age of 14 he read books from the library and gained the knowledge he needed to built a 12 watt wind generator from junk parts. Wow!

We’re pretty used to hearing about creative people who end up getting punished for their hacks. Fortunately he has been rewarded for his brilliance. He’s now studying at the African Leadership Academy in Johannesburg with a well-deserved scholarship.

His story comes to the surface now because a book about his experiences has just been released. We need more people like this, and they should be rewarded for their efforts like he has been. We’ve put the book on our hold list at our Public Library and can’t wait to gain some knowledge from [William’s] experiences.

Check out his short talk at the TED conference, embedded after the break. Continue reading “Hacker Rewarded For Creating Electricity” →

Power Generating Backpack

October 1, 2009 by 28 Comments

[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.

Seawater Cooled Data Centers

September 22, 2009 by 89 Comments

swac-mauritius

Remember Mauritius from High School geography? We didn’t either, but apparently it’s a small island nation east of the southern tip of Africa. It seems they are trying to develop an industry in eco-friendly data centers. The plan is to use a pipeline to gather cold water from the ocean, run it two miles to the island, and use it as inexpensive cooling. Because rooms packed with servers generate copious amounts of heat it’s easy to see how this can reduce the cost of maintaining a data center.

The thing that struck us here is, how eco-friendly is this? The article mentions that this technology is fairly mature and is already used in several places. With that in mind, isn’t this just another way to raise the temperature of the oceans, or does the environmental savings of not using electricity or gas to produce the cooling offset this?

[Thanks Vesanies]

Tapping Tree Power

September 10, 2009 by 51 Comments

[bugloaf] tipped us off about this flower power hack. University of Washington researchers, [Babak], [Brian], and [Carlton] have developed very low power circuits to run directly off of trees. This builds upon the work of MIT researchers and Voltree Power. A voltage of up to around 200mV is generated between an electrode in a tree and an electrode in the ground. Identical metals can be used as electrodes as the process is not like that of a lemon or potato battery. The significant development here is the use of a boost converter and exceptionally low power circuits. What kind of applications can you come up with for this source of power? Maybe you could try to combine this power with the power from donuts and hair.

12kW Solar Collector

September 9, 2009 by 57 Comments

[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” →

DIY Solar Panels

September 8, 2009 by 74 Comments

solar

Reader [unangst] pointed out to us an article in the U.K.’s Daily Mail, where a teenager from Nepal had managed to create a 9v, 18W solar panel using human hair rather than the usual semiconductors (usually crystalline-silicon). The complex silicon in solar panels are what keep the prices out of reach of developing nations, and while there are a number of new technologies that are helping  bring down the cost, [Karki] managed to make his solar panel for only £23 (roughly $38). He also claims that when mass produced the price could drop substantially down to under $10 a panel, which would shatter the $1/watt sweet spot.

The melanin in hair acts as an organic-semiconductor, and while the hair does not have the longevity that silicon panels have (months rather than years), these panels can be made cheaply and serviced with little to no complex knowledge. Using melanin as an organic semiconductor seems to be a newer idea, because information seems hard to come by, but we managed to find a research paper from 2007 that explored the energy absorption attributes of melanin, as well as some good background info for the science types.

Research Paper (Warning: PDF)

So, Hack a Day readers, which one of you is going to make your home-brew solar panels first? Let us know when you do.

Thanks [unangst].

[digg=http://digg.com/environment/Teenager_Makes_DIY_Solar_Panels_from_Hair_Hack_a_Day]