Big LED Breakthrough at Purdue University Could Change the World

by Michael Graham Richard, Gatineau, Canada on 07.22.08

Better, Cheaper LEDs
The incandescent lightbulb that wastes 90% of the electricity as heat is dying, we all know that. But a new breakthrough in solid state lighting might also kill compact fluorescent lightbulbs (CFLs) faster than some expected. Scientists at Purdue University have figured out how to manufacture LED solid-state lights on regular metal-coated silicon wafers (more details below). What this means is: much lower costs.

10% Reduction in Total Electricity Use
And since about 1/3 of U.S. electricity is used to produce light, this is major. "If you replaced existing lighting with solid-state lighting, following some reasonable estimates for the penetration of that technology based on economics and other factors, it could reduce the amount of energy we consume for lighting by about one-third. That represents a 10 percent reduction of electricity consumption and a comparable reduction of related carbon emissions," said Timothy D. Sands, professor of Materials Engineering and Electrical and Computer Engineering states at Purdue.

Old LEDs vs. New LEDs
What makes traditional LEDs so expensive is that the light-emitting layer of an LED light is a gallium nitride crystal and it needs to be treated in various ways with expensive materials.

Dailytech:

In sapphire based LEDs, used for green or blue lighting, mirror-like reflectors are need to reflect and resend emitted light, increasing the efficiency. Typically, this layer is extremely expensive to produce, part of the reason the current generation of LED lighting costs so much,costing at least 20 times more than conventional incandescent and fluorescent bulbs. Also, the LEDs are built on sapphire crystals, which provide the color, but are extremely expensive.

But the new LEDs can be made using standard silicon wafers and already existing, less expensive, processes. This would make them competitive with incandescent and CFLs.

The new techniques yield a crystalline structure aligned to the crystalline silicon. This means that the LEDs are less prone to defects and will perform more efficiently [...] silicon dissipates heat more effectively than sapphires. This will reduce damage during operation and lead to longer lifetimes and more reliability..

We might soon have to get used to changing lightbulbs every other decade.

LEDs that are currently available convert electricity to light with an efficiency of 47 to 64%. It is predicted that LED produced with Purdue's process would have an efficiency in the high-end of that range, compared to about 10% for incandescent.

LED Street Lights are Coming

by Michael Graham Richard, Gatineau, Canada on 05.28.08

New Foothold for LED Lights
Dusseldorf, Germany, has 17,000 gas street lamps. The city's power utility has decided to replace 10,000 of them with LED street lights, but that hasn't happened yet. So far, only about 25 of them have been installed.

Of course, LED are still kind of expensive, so there's a capital cost. But once they are in place, their operating costs are lower and they can last for a very long time. Another benefit is that you can direct light much more easily, so you can avoid sending light in all directions (people with a street light across the street from their bedroom window will understand...). The first bump in the road for LED street lights was that some people thought their white light was too cold compared to the red-ish glow of the old lamps, but that can easily be fixed by using colored LEDs. ::Replacing gas lamps with LEDs

10 Ways to Go Green and Save Green

How can we live lightly on the Earth and save money at the same time? Staff members at the Worldwatch Institute, a global environmental organization, share ideas on how to GO GREEN and SAVE GREEN at home and at work.

Climate change is in the news. It seems like everyone's "going green." We're glad you want to take action, too. Luckily, many of the steps we can take to stop climate change can make our lives better. Our grandchildren-and their children-will thank us for living more sustainably. Let's start now.

We've partnered with the Million Car Carbon Campaign to help you find ways to save energy and reduce your carbon footprint. This campaign is uniting conscious consumers around the world to prevent the emissions-equivalent of 1 million cars from entering the atmosphere each year.

Keep reading for 10 simple things you can do today to help reduce your environmental impact, save money, and live a happier, healthier life.

1. Save energy to save money.

   
   Armistead Booker/flickr
   • Set your thermostat a few degrees lower in the winter and a few degrees higher in the summer to save on heating and cooling costs.
   • Install compact fluorescent light bulbs (CFLs) when your older incandescent bulbs burn out.
   • Unplug appliances when you're not using them. Or, use a "smart" power strip that senses when appliances are off and cuts "phantom" or "vampire" energy use.
   • Wash clothes in cold water whenever possible. As much as 85 percent of the energy used to machine-wash clothes goes to heating the water.
   • Use a drying rack or clothesline to save the energy otherwise used during machine drying. If you must use a dryer, consider adding dryer balls to cut drying time.

2. Save water to save money.

   • Take shorter showers to reduce water use. This will lower your water and heating bills too.
   • Install a low-flow showerhead. They don't cost much, and the water and energy savings can quickly pay back your investment.
   • Make sure you have a faucet aerator on each faucet. These inexpensive appliances conserve heat and water, while keeping water pressure high.
   • Plant drought-tolerant native plants in your garden. Many plants need minimal watering. Find out which occur naturally in your area.

3. Less gas = more money (and better health!).

   
   richardmasoner/flickr
   • Walk or bike to work. This saves on gas and parking costs while improving your cardiovascular health and reducing your risk of obesity.
   • Consider telecommuting if you live far from your work. Or move closer. Even if this means paying more rent, it could save you money in the long term.
   • Lobby your local government to increase spending on sidewalks and bike lanes. With little cost, these improvements can pay huge dividends in bettering your health and reducing traffic.

4. Eat smart.

   • If you eat meat, add one meatless meal a week. Meat costs a lot at the store-and it's even more expensive when you consider the related environmental and health costs.
   • Buy locally raised, humane, and organic meat, eggs, and dairy whenever you can. Purchasing from local farmers keeps money in the local economy.
   • Watch videos about why local food and sustainable seafood are so great.
   • Whatever your diet, eat low on the food chain [pdf]. This is especially true for seafood.

5. Skip the bottled water.

   • Use a water filter to purify tap water instead of buying bottled water. Not only is bottled water expensive, but it generates large amounts of container waste.
   • Bring a reusable water bottle, preferably aluminum rather than plastic, with you when traveling or at work.
   • Check out this short article for the latest on bottled water trends.

6. Think before you buy.

   
   Michael Reinhart/flickr
   • Go online to find new or gently used secondhand products. Whether you've just moved or are looking to redecorate, consider a service like craigslist or FreeSharing to track down furniture, appliances, and other items cheaply or for free.
   • Check out garage sales, thrift stores, and consignment shops for clothing and other everyday items.
   • When making purchases, make sure you know what's "Good Stuff" and what isn't.
   • Watch a video about what happens when you buy things. Your purchases have a real impact, for better or worse.

7. Borrow instead of buying.

   • Borrow from libraries instead of buying personal books and movies. This saves money, not to mention the ink and paper that goes into printing new books.
   • Share power tools and other appliances. Get to know your neighbors while cutting down on the number of things cluttering your closet or garage.

8. Buy smart.

   • Buy in bulk. Purchasing food from bulk bins can save money and packaging.
   • Wear clothes that don't need to be dry-cleaned. This saves money and cuts down on toxic chemical use.
   • Invest in high-quality, long-lasting products. You might pay more now, but you'll be happy when you don't have to replace items as frequently (and this means less waste!).

9. Keep electronics out of the trash.

   
   Gaetan Lee/flickr
   • Keep your cell phones, computers, and other electronics as long as possible.
   • Donate or recycle them responsibly when the time comes. E-waste contains mercury and other toxics and is a growing environmental problem.
   • Recycle your cell phone.
   • Ask your local government to set up an electronics recycling and hazardous waste collection event.

10. Make your own cleaning supplies.

    • The big secret: you can make very effective, non-toxic cleaning products whenever you need them. All you need are a few simple ingredients like baking soda, vinegar, lemon, and soap.
    • Making your own cleaning products saves money, time, and packaging-not to mention your indoor air quality.