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Thursday, 4 June 2009

LEDs - Light up The World Foundation.

In my previous post, I felt that I had not done full justice to LED lighting and to the people behind The Light up The World Foundation (Lutw).

The Light Up The World Foundation (Lutw) aims to bring efficient, durable and near permanent White Light Emitting Diodes (WLED) lighting solutions powered by renewable energy to the world's poor in ecologically sensitive and remote rural areas. Lutw support their engagement by quoting Lawrence Berkeley National Laboratories (LBNL) as saying that, "the primary source of greenhouse gas emissions in the developing world comes from dirty, hazardous and expensive fuel-based sources such as kerosene for lighting.

LBNL states explicitly that the only real way to meet the increasing lighting energy demands is to replace fuel based lighting with solid state lighting systems."

History of the foundation from their website:
Scots born, Dr. David Irvine-Halliday, a Professor of Electrical Engineering at the University of Calgary, had in 1997 the vision to use LED lighting to bring practical, economical, and environmentally safe lighting to the developing world.

Dave, who had been working with LEDs for more than two decades, spent most of 1997 and 1998 trying to make an acceptable white light from various combinations of colored indicator LEDs. He made white light but it was simply not bright enough to be of any practical use in the developing world. Around the end of 1998 Dave discovered that Nichia, a Japanese company, had invented the White LED a few years earlier and he immediately requested that they send him samples. When he and his technician, John Shelley, lit their very first White LED it was most definitely the “Eureka” moment – “Good God John, a child could read by the light of a single diode”.

(cf. my own home experience in the previous post whereby I can read comfortably with an 18 diode,spot of 1W. "a wee Eureka" but I did not say that I bought my second packet 2 spots at half price because this product was not selling well. A pity that I did not have more of the suitable sockets, great for directional bedside reading!)

My own first encounter with "Light Up The World" dates back roughly to 2005 when creating my first personal pages drawn-up to document my personal experience, publications and writings. The latter link many be given only upon request.

More history...

Short summary -" What are LEDs". (quoted from Lutw.org)
- LEDs are made from layers of different semi-conductor material formed on a sapphire substrate, one on top of the other using a process called Epitaxial crystal growth
- About 13,000 LEDs can be formed on the substrate which can be about .25 x.25 units in size
- Tiny gold contacts are applied to each chip site
- Each individual chip is packaged to form a lighting device

Much of the current research appearing recently in science break-through alerts aims to further reduce the materials and manufacturing cost of WLEDs

More on technology from Lutw...

Strategic Alliances and Project Management Lessons_case study.

Arcadis Greystone
Canadian Hydro Developers
Carmanah Technologies Corporation
Kyocera Solar
Philips Lumileds
Luxeon Star LEDs
Nemalux LED Lighting
SunEnergy Power International
University of Calgary

"LUTW has grown from a single idea to a global humanitarian organization that is the leader in its field. Each step, and each increase in capacity, has been the result of collaborative effort.

It is an excellent example of the mutually beneficial results and opportunities created through partnerships. These include major industrial partners, NGO's, local communities and academia. LUTW is able to create strong relationships with various groups in many capacities, through its ingenuity and commitment to making positive changes in the world. LUTW will continue to build strong partnerships to deliver high quality projects and reach more people in need."


A wealth of further information is available on Lutw's media section.


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