Archive for September, 2010

Posted by hugo at 12 September 2010

Category: News, Research

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Graphite Foam

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.

Posted by hugo at 12 September 2010

Category: News

Tags: , ,

  World’s Largest Wave Power Hub Goes Live

World’s Largest Wave Power Hub Goes Live

Over in the UK we like to do things … well, a little differently. That stiff upper lip nonsense was always a bit of a ruse, hiding a reckless ability to do those things sane human beings would never think of doing.

Like slinging a live four way power socket into a bath tub. Zap, you’re dead .. as the saying goes.

Yet this is precisely what’s been going on off the south west coast of Britain but with two crucial differences: the four huge plugs (like the one pictured) are designed as energy receivers, not emitters; and the Atlantic Ocean is a wee bit bigger than your average bathtub.

Ten miles off the Cornish town of Hayle, 180 feet below the sea, lies a 12 tonne four way plug which cost $64 million to build and install. Called the Wave Hub, it can have four 5MW marine power devices connected to it at any one time and is connected to the main national grid by a 15 mile length of cable.

Now, 5MW is peanuts compared to some of the projections for marine power installations; for example just up the coast it’s been estimated that the world’s largest tidal power generator could generate 187,000 MWh/year.

However permanent installation is not the aim of the Wave Hub. Rather, it’s all about providing a live scenario test bed for marine energy developers to come and test and tweak their inventions. If it just so happens it provides energy for 20,000 homes, then so much the better!

The first testers scheduled at the Wave Hub are New Jersey based Ocean Power Technologies, whose buoy based design is already live off the north coast of Spain. Their stint at the Wave Hub is to test out a new design which would see the buoys’ output increase by over three times.

SOURCE: GO Media – Written by Chris Milton

Posted by hugo at 12 September 2010

Category: News

Tags: , ,

Most powerful LED

Most powerful LED

In a truly staggering breakthrough in LED intensity that will have wide ramifications on electricity use worldwide, the Finnish LED producer Obelux has developed by far the most powerful LED of all time.

In response to aviation industry requests, Obelux created a flashing High Intensity LED that delivers 200,000 candelas. Current technology delivers just 10 candelas. This marks an incredible 20,000-fold improvement on the old Xenon technology.

These will be installed on over 150 meter tall buildings and masts, replacing the flashing red aviation obstacle lights that are currently in place on masts and tall buildings to warn airplanes. Boosting brightness even further, they will be in groups of three, so that each can deliver 600,000 candelas.

Energy consumption? Just 350 watts!

Source: Simple Green

Posted by hugo at 12 September 2010

Category: News

Tags: , , ,

tree

Trees please

Arbor Month have started and the focus are yet again on the importance of trees. Trees are a key tool in the fight against global warming in the world. The national theme for Arbor Month 2010 is “Plant for the plant – grow green “. This theme wants to bring the following greening messages across to the nation :

  • Plant trees ,save our environment.
  • One house , one tree.
  • Plant them today – save the future.

Source: Simply Green