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

The Switzerland-based environmental group conducts a yearly examination of plant and animal species and 2009’s list topped last year’s by 2,800. However, the group admitted that the list is incomplete, and there remain millions of other specimens yet to be surveyed.

Rabb’s fringe-limbed tree frog

Among the new animals to be included in the list is Rabb’s fringe-limbed tree frog, discovered merely four years ago. It is but one of the 1,895 amphibians that could soon die out like the Kihansi spray toad of southern Tanzania (pictured above) which is known to be extinct in the wild. In fact, the fringe-limbed tree frog is threatened by the same fungal disease that killed off the Kihansi spray toads. This disease called chytridiomycosis is thought to have spread and reached Panama through international trade and global warming.
Source: Simply Green

Solar roof tiles

What is the true cost of solar power? The answer to this question may determine whether or not you decide to install solar panels on your home or business. In fact, in the current economy, everyone is worried about investments, and whether they make sense long term.

How does the cost of solar power factor in?

In order to accurately determine solar energy cost, you’ll need to consider a range of factors. Get your pencil out… you should write these down:

1. Current utility bills, averaged on a monthly basis
2. Projected future utility bills, over your estimated years of ownership of the property
3. Amount you may save annually in electricity bills
4. State and provincial solar energy tax rebates and other incentives, such as no money down
5. Type of solar panel system you want to install: PV Panels or Solar roof shingles
6. Other potential energy savings, through energy efficient bulbs, shutting off lights, adjusting thermostats
7. Other potential energy retrofitting measures, including windows, insulation, Energy Star appliances, etc.

When you consider the fact that solar power is free, once you install the panels, it may be worth it to consider converting now.

Case in point

Let’s say that your solar panel system will cost you R20,000.  Now, consider that your monthly electricity bills average R600 a month, which is R7,200 a year. That alone would be about a 3-year return on investment, but wait! What about the increase in value of your home? If you can save the entire R7,200 a year, multiply that figure by 20 which is the typical loan period you get R144,000.   That’s right: R144,000 in additional property value!

Eskom tarif hike

Now, add in the rising electricity rates that you won’t have to worry about. Oh, and the cost of continued global warming – you are doing your part you know… priceless!

You see, it just takes some focused arithmetic to determine the true cost of solar power. Think beyond your initial investment/outlay, and I’ll bet you will soon see that solar energy is the way to go, without requiring you to break the bank.
Source: Solar Panel | Green Power

In the same way that a bigger battery will provide more power for longer, a larger Solar panel will collect more energy in less time. The right size of panel will depend on variables such as the power required by the appliance, the length of time you want to use it and how much sunshine you get at the time of year.

2. There are three things to consider when choosing a solar panel or creating a solar system.

You need to know what appliances you will be using and how much energy they require, how much energy your battery can store and which solar panel will replenish your ‘stock’ of energy in the battery in line with your pattern of use.

3. How much energy will your appliance(s) use over a period of time?

The power consumption of appliances is given in Watts (e.g. 21” fluorescent light, 13W). To calculate the energy you will use over time, just multiply the power consumption by the hours of use.  The 13W light fitting, on for 2 hours, will take 13 x 2 = 26Wh from the battery.  Repeat this for all the appliances you wish to use, then add the results to establish total
consumption.

4. How much energy can your battery store?

Battery capacity is measured in Amp Hours (e.g. 17Ah). You need to convert this to Watt Hours by multiplying the AH figure by the battery voltage (e.g. 12V).  For a 17Ah, 12V battery the Watt Hours figure is 17 x 12 = 204Wh.  This means the battery could supply a 13W fluorescent for 15 and a half hours, 204W for 1 hour, or 102W for 2 hours, i.e. the more energy you take, the faster the battery
discharges.

5. How much energy can a solar panel generate over a period of time?

The power generation rating of a solar panel is also given in Watts (e.g. STP010, 10W).  To calculate the energy it can supply to the battery, multiply Watts by the hours exposed to sunshine, then multiply the result by 0.85 (this factor allows for natural system losses).  For the solar 10W panel in 4 hours of sunshine, 10 x 4 x 0.85 = 34Wh. This is the amount of energy the solar panel can supply to the battery.

Source: GreenWeld

From his work with rotary magnetic fields, Tesla devised a system for generation, transmission, and use of AC power. He partnered with George Westinghouse to commercialize this system. Westinghouse had previously bought the rights to Tesla’s polyphase system patents and other patents for AC transformers from Lucien Gaulard and John Dixon Gibbs.

Several undercurrents lay beneath this rivalry. Edison was a brute-force experimenter, but was no mathematician. AC cannot be properly understood or exploited without a substantial understanding of mathematics and mathematical physics, which Tesla possessed. Tesla had worked for Edison but was undervalued (for example, when Edison first learned of Tesla’s idea of alternating-current power transmission, he dismissed it: “[Tesla's] ideas are splendid, but they are utterly impractical.”^[3]). Bad feelings were exacerbated because Tesla had been cheated by Edison of promised compensation for his work.^[4][5] Edison would later come to regret that he had not listened to Tesla and used alternating current.^[6]

Source: Wikipedia