Nepalese teenager replaces silicon with human hair for cheap solar energy

Solar panel made using human hair costs 75% less than conventional solar cells.

Milan Karki, born in one of the poorest countries in the world - Nepal, has tried to end energy crisis in the country and the world with a solar panel that is about 75% cheaper than industrial made solar panels of comparable capacity.

The secret to this low-cost solar panel is not as hi-tech as one would imagine as all the teenage inventor did was to replace the expensive silicon normally used in solar cells with a comparably cheaper product – human hair. The young inventor says that human hair due to the presence of Melanin is sensitive to light and also acts as a type of conductor.

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The panel produced using this technique costs around £23 and produces 18W of power at 9V.The inventor believes that if the product is mass produced, the panel could be made available in developing countries at half that price, which would make it four times cheaper than other panels available on the market today.

Electronic Tree

Researchers harness potential difference between a tree and the soil to power tiny electrical circuits.

Trees are known to provide cooling, oxygen and shade, but a new research conducted by scientists at the University of Washington has proved that trees can provide something that not many would have thought of before – electricity. The scientists have successfully powered tiny electrical circuits with nothing more than the energy they harnessed from bigleaf maples.

A similar research conducted at the Massachusetts Institute of Technology found that plants generate a voltage of about 200mV when one electrode is placed in the plant and the other in the surrounding soil. The UW team carried the research forward by connecting a custom boost converter that works for input voltages of as little as 20mV and produces an output of about 1.1V, which is enough to run low-power sensors.


While the new research won’t end the energy crisis anytime soon, it can be used as a low-cost option for powering tree sensors that might be used to detect environmental conditions, forest fires or simply the health of the tree.

Serve your Soldiers

Recycling campaign converts trashed cellphones into prepaid calling cards.

For soldiers serving overseas, getting in contact with their tensed family members is not that easy. A campaign in Lady Lake, a small town in Florida, can help these brave men get in touch with their family by encouraging people to donate their cellphones, which are recycled and turned into 250-minute prepaid calling card.

Initiated by the Lady Lake Police Chief Ed Nathanson, the “Help Them Call Home” campaign encourages people to donate unwanted cellphones or make cash donations, to allow the organizers to get prepaid calling cards for the soldiers serving overseas. A $40 donation translates to one 1200 minute calling card, while a donated phone means one 250 minute calling card.

The campaign has till date resulted in $5000 worth of calling cards being sent overseas for the soldiers. Although Lady Lake has collected more than 5000 cellphones, the organizers believe that this year they can get more than 2000 unwanted cellphones.

Natural Protector

Roof planting system to convert to green roofs.

With the world being turned into concrete jungle, roofs of houses and other commercial and residential buildings offer a green hope. They can be turned into solar energy generating plants or if you don’t want to spend that much on green power, then the other alternative is converting roofs into green roofs.


This conversion into a green roof comes with two advantages – one being the availability of food and it also lowers the solar heat gain, thereby reducing the amount of energy required to cool the interiors. Industrial designer Kyoungho Ha is trying to help the masses in the conversion process with a system dubbed Natural Protector.