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.

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

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

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

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

Solar power is cheaper than nuclear

The Holy Grail of the solar industry — reaching grid parity — may no longer be a distant dream. Solar may have already reached that point, at least when compared to nuclear power, according to a new study by two researchers at Duke University.

It’s no secret that the cost of producing photovoltaic cells (PV) has been dropping for years. A PV system today costs just 50 percent of what it did in 1998. Breakthroughs in technology and manufacturing combined with an increase in demand and production have caused the price of solar power to decline steadily. At the same time, estimated costs for building new nuclear power plants have ballooned.

The result of these trends: “In the past year, the lines have crossed in North Carolina,” say study authors John Blackburn and Sam Cunningham. “Electricity from new solar installations is now cheaper than electricity from proposed new nuclear plants.”

Source: The Energy Collective

Should we worry about engineering algae for biofuels?

The Great American Algae Rush is in full swing.

Dozens of companies and hundreds of scientists are working hard to engineer algae to produce green — literally and figuratively — fuel.

The endeavor is at the crossroads of energy and science, and the trend is spreading worldwide.Why? Because some algae strains can produce 10 or more times more fuel per acre than the corn that is used to make ethanol, or the soybeans used to make biodiesel.

Better still, you can grow algae on arid land and in brackish water, which avoids competing with food production, unlike the corn and soybeans that coat much of the Midwest’s farmland.

Best of all: algae consume carbon dioxide, combating greenhouse gas emissions.

But a new profile of the industry in the New York Times demonstrates that this technology has its share of pitfalls.

For one, efforts to engineer and manipulate the organisms has environmentalists concerned because algae are the base of the marine food chain.

For example: Screw up and over-engineer a strain, and suddenly you have an organism that’s out of whack with the biosphere, stripping water of its oxygen and harming fish — and maybe humans — in the process.

Source: Simply Green

25% solar by 2050

The International Energy Agency (IEA) presented two new solar energy analyses in Valencia, Spain this week, a Solar Photovoltaic Energy Technology Roadmap and a Concentrating Solar Power Technology Roadmap.

The key finding from these is that 20-25% of global electricity production could be from solar energy by 2050.

In a blog post on our sister site, One Block Off the Grid, I just discussed how the United States and how rooftop solar fit into this. Below, mostly from the reports themselves, is a short discussion of what government’s role in all of this needs to be.

Source: Simply Green

$100 Billion Opportunity

Here’s an opportunity to wisely spend some of the $100 billion that Secretary of State Hillary Clinton promised at Copenhagen to cut the greenhouse gases of developing nations by aiding in the development of renewable energy infrastructure to by-pass fossil fuel dependence. (Previous story.)

Apparently one in four Chinese cities and seven out of 10 counties are without sewage-treatment plants, according to the People’s Daily. While there are many ways to treat sewage or municipal waste; one of the newest is the use of municipal solid waste to make renewable energy.

Converting waste to energy is done in several ways. One is making bio-gas from sewage (human or animal) to run gas-turbine driven electric power plants.

Another is to create a biofuel, such as that used by nearly every vehicle in Sweden’s fifth largest city Linköping. Greenhouse gas emissions there were reduced as much as 90% with the technology. It helped Sweden achieve a 9% below-Kyoto emissions cut with simultaneous 44% economic growth.

This presents an opportunity to kill two birds with one stone; by building the infrastructure in the developing world that uses municipal solid waste to make renewable energy. This would cut the greatest source of the rise expected in greenhouse gas emissions from fossil fuel use in the next decades: from fast-developing nations like India and China.

The developed world evolved water treatment technologies well before our knowledge of climate change drove us to invent uses for municipal solid waste as a source of renewable energy with no greenhouse gas emissions.

But now, nations that do not already have any sewage treatment infrastructure in place are well placed to leapfrog the developed world, which is only just starting to tap into waste-to-energy from municipal solid waste, or sewage.

For all kinds of municipal waste-to-energy companies, this presents a huge opportunity. The developed world has pledged $100 billion to develop renewable energy in the developing world. As I noted here, that money is not charity – as it is incorrectly framed in most media reports (previous story), but it will go to the renewable energy companies from those nations that get there first. This waste-to-energy plant pictured is from a New Zealand company that has apparently already built numerous large facilities throughout Asia.

Source: Simplygreen

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