Tag: electricity
Graphite Foam Makes High Efficiency LED Lights Last Longer
by mc on Sep.12, 2010, under News, Research
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.
World’s Largest Wave Power Hub Goes Live
by mc on Sep.12, 2010, under News
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
Zille unveils four-year plan for green Cape
by mc on Jul.27, 2010, under News
The provincial government plans to have 15 percent of all electricity used in the Western Cape generated from renewable energy sources – like wind, wave and solar – by 2014.
It also aims to reduce electricity use in selected schools and hospitals by between 5 and 10 percent, and to reduce the provincial product-to-carbon emission ratio by 10 percent, also by this date, as part of its climate-change mitigation efforts.
Source: IOL
Why WWF thinks flicking the switch for Earth Hour is worth it
by mc on Mar.27, 2010, under News
Tomorrow, at 8.30pm, thousands of people across the UK and maybe a billion across the world will take part in Earth Hour.
It’ll look impressive, no doubt. The big switch-off will make the news. But so what? We know that just one hour, even on this global scale, won’t in itself save energy or reduce emissions in any significant way. This is a giant photo opportunity – eye-catching and symbolic, yes – but how can it really make a difference? More importantly, why would a science-based organisation like WWF believe this is worth the effort?
I think there are many reasons, but there are three worth focusing on.
Firstly, climate change is a threat truly global in its nature. It demands global attention, commitment and action. In December last year, as the climate talks in Copenhagen came to a stuttering finish, many in the UK felt disappointed and disillusioned. But talking to my colleagues working in areas of the world already feeling the effects of climate change, emotions ran much higher. Anger and disbelief best describes what nations like the Maldives, Bangladesh and Tanzania felt on seeing the failure of world leaders to take collective responsibility. They are seeing the effects of climate change now. It is, for countries in their position, no theory for debate or distant possibility.
As I write, more than 125 countries have confirmed their participation in Earth Hour, almost 40 more than in 2009, including 56 national capitals and eight of the 10 most populated metropolises on the planet. “Earth Hour” has appeared more than 30m times online in the past 24 hours and is currently one of the top 10 trending topics on Twitter. While the UK and the US (two major global emitters) may have seen an increase in sceptical noise on climate change in recent months, I feel confident that globally, this is no waning movement.
Secondly, politicians here in the UK need a mandate to act. Unlike elsewhere in the world, our main political parties all understand the threat of climate change and say that they are committed, albeit with different policies and approaches, to dealing with the problem. However, Copenhagen largely failed and leaders need us, the voters, to keep up a demand for action.
This close to a general election, there’s no better time to make a big, bold, collective statement that as a public, we expect leadership from our next government, whatever its hue. Schools, cathedrals, large companies, small businesses, pubs, clubs, councils all add up to a pretty comprehensive slice of our population and just this week, under pressure from Earth Hour participants, supporters and many committed MPs, the Palace of Westminster and 10 Downing Street joined the Senedd in Cardiff and the Scottish parliament in Holyrood and signed up to switch off. In the US, 31 state governors are supporting Earth Hour. The people who matter do notice.
Lastly, Earth Hour is for me a brilliant analogy for how we can get to a solution. Climate change will demand big, global ambition from world leaders – the “landmarks” of our political landscape. Just as lights go off at Christ the Redeemer, the Empire State Building and the Forbidden City, we need Presidents Lula da Silva, Obama and Hu Jintao and many others to work together in order to get a binding commitment to reduce emissions.
A low-carbon future will demand small changes from all of us at home, like the families taking part in Earth Hour, perhaps eating their dinner by candlelight. Better insulation, more efficient heating, using public transport and the products we choose to consume can all have impact on the energy we use and reduce our personal impact on our environment.
Earth Hour is not about a world without light, power and the great human achievements that keep us warm and safe. It is absolutely a celebration of their positive role; we want a bright future in which the lights stay on, drawing on forms of energy and innovative technologies that have a lesser impact on people and nature around the world. As the 10:10 campaign has shown alongside Earth Hour, collective action can have an impact.
We know that a single hour, once a year is not enough. But also we know that there is no greater, global call to action available at the flick of a switch. We firmly believe Earth hour is worth it.
Source: Guardian
What will you do in the dark for Earth Hour?
by mc on Mar.27, 2010, under News

What will you do by candle-light during Earth Hour?
This Saturday night, hundreds of millions of people will turn their lights off in a symbolic gesture for WWF’s Earth Hour. Setting aside the question of why they’re at home on Saturday night, I wonder if those millions have actually considered what they’re going to do while the lights off, aside from firing up another light in the shape of the telly or another screen?
Some participants, like Malcolm Handoll in Orkney, clearly have commendable ideas already, such as “games, candlelit dinners, chatting with friends around a fire, a walk in the park”. But as a public service for anyone who’s signed up without a plan, here are some suggestions on things to do in the dark.
One bright suggestion from the environmentguardian.co.uk team is making shadow puppets on the wall with a torch. I recommend a cracking book I received at Christmas on this art, Hand shadows to be thrown upon a wall, a Ronseal slither of a title written by a chap called Henry Bursill in 1860 to entertain his kids. Hours of fun – or ten minutes, at least.
Other ideas from Guardian towers included looking at the stars – hopefully easier with Earth Hour’s temporary drop in light pollution – meditating, going for a run, doing press-ups or, like Malcolm, having a candlelit dinner. My own suggestions are heading to the high ground in a city to watch the lights go out in a kind of inverse Fireworks night, getting a boardgame out (Scrabble on a table still beats the iPhone version), or going to bed early for sleep and sex (Care2 suggests tantric, but is an hour really long enough for that?).
You could also be very retro and go in for a bout of storytelling, as some people recall doing during the 1970′s power cuts, or take WWF up on its idea of a candlelit quiz on animals, green living and other topics. Elsewhere on the web, Suitably Desparing’s blogger is weighing up listening to a wind-up radio against seeing Edinburgh’s landmarks, while Vancouver’s magazine Granville has a good roundup of ideas from last year, including the obvious one I’ve missed so far – making music.
That’s the limit of my imagination, social circle and web trawling; what are your, probably better, ideas for things to do in the dark this weekend?
Source: Guardian



















