Graphite Foam

Chalk up another reason to make the switch to high efficiency LED lighting: Scientists at the Oak Ridge National Laboratory have developed a graphite foam that extends the life of LED lights. The foam is used as a passive cooling element, which plays a critical role in the lifespan of LED components. The breakthrough could help lower the cost of LED’s and make them more attractive in the mass market.

A wholesale switch to high efficiency LED technology could be part of the solution to the conundrum posed by the coming wave of new electric vehicles, which is how to manage overall energy consumption (and carbon emissions) when millions of new electric car owners start charging up their vehicles.

LEDs and Temperature

LED stands for light emitting diode, which is a technology for producing light through a chemical reaction (in contrast, incandescent lights work by burning a filament). Though they use less electricity than conventional lights, one drawback is their sensitivity to temperature. According to Oak Ridge, each 10-degree decrease in the temperature of an LED can double its lifespan. For this reason, LEDs are designed with “heat sink” components usually made of copper or aluminum.

Advantages of Graphite Foam for Cooling LEDs
Graphite foam is a lightweight material with a distinctive graphite crystal structure (graphite is a form of carbon, by the way – same chemical elements but different structure). The structure “wicks” heat away from the source and conducts it away without the need for mechanical cooling. Compared to copper and aluminum components, graphite foam is lighter and easier to work with, admitting the possibility of designing cheaper but more effective cooling elements for LEDs.

Source: GO Media – Written by Tina Casey – Image (altered): Foam by James Cridland on flickr.com.

The Story of Bottled Water, releasing March 22, 2010 on storyofbottledwater.org, employs the Story of Stuff style to tell the story of manufactured demand—how you get Americans to buy more than half a billion bottles of water every week when it already flows from the tap. Over seven minutes, the film explores the bottled water industry’s attacks on tap water and its use of seductive, environmental-themed advertising to cover up the mountains of plastic waste it produces. The film concludes with a call to ‘take back the tap,’ not only by making a personal commitment to avoid bottled water, but by supporting investments in clean, available tap water for all.

TV says

Highly conductive paper for energy-storage devices

Stanford scientists have developed featherweight, pliable batteries and supercapacitors in the form of everyday paper.

By coating a sheet of paper with ink made of carbon nanotubes and silver nanowires, the scientists were able to construct a highly conductive storage device that’s both low-cost and high-performance.

(The difference between a battery and a capacitor, you ask? both hold energy to be converted to electricity, but capacitors hold it for a shorter period of time. On the other hand, they can store and discharge energy much more rapidly.)

The batteries are so strong that you can crumple them and the performance does not degrade.Led by assistant professor of materials science and engineering Yi Cui, who previously created nano-size batteries using plastics, the researchers developed a solution that is more durable than conventional batteries.

Source: Smart Planet

Green algae known as Cladophora

A new biodegradable battery made of cellulose promises to offer thin, flexible, lightweight, inexpensive and environmentally-friendly batteries made without metal parts.

The battery is made from green algae known as Cladophora, found along freshwater beaches around the world.

The key to the battery’s success is its large surface area. Made from algae-derived cellulose with 100 times the surface area of the cellulose found in sheets of notebook paper, the battery can manage far more conducting polymer than in previous incarnations.

That means better recharge, hold and discharge capabilities.

Source: Smart Planet

Barbara Ettinger

Award-winning environmental filmmaker Barbara Ettinger’s latest documentary is about a topic so obscure that even some COP15 attendees haven’t heard of it: ocean acidification. But it’s also a topic of critical importance that threatens human survival. The film, A Sea Change, follows Ettinger’s husband, Sven Huseby (the co-producer of the film and a retired history teacher) in his quest to discover what’s happening to the world’s oceans. He finds that global warming is just part of the problem.

Source: Smart Planet