This is Gwen Outen with the VOA Special English
A light emitting diode, or
L.E.D., is a device that shines when electricity passes through it. But it
works differently than traditional kinds of light bulbs. Light emitting
diodes use less energy and last much longer than bulbs with a filament inside. L.E.D.'s are also
cooler to the touch, and shine a lot brighter than they used to.
Red L.E.D.'s have long been used as signal lights on electronic
equipment. But now light emitting diodes also come in blue and other
colors. Colored L.E.D.'s are used to show images on everything from
wireless phones to huge video signs. And white L.E.D.'s are being used
increasingly to replace traditional lighting systems.
But all these require electricity. In poor countries, people often burn
fuel to produce light. But the smoke can make people sick. So an
electrical engineering professor from Canada started a project to produce
L.E.D. lighting systems for the developing world.
These lights are powered by batteries that can be recharged with energy
from the sun. The batteries can also be charged through other ways, such
as wind power, water power or pedal power. Someone sits and pedals a wheel
connected to a generator.
Professor David Irvine-Halliday tells the story of how he got the idea.
In 1997, while climbing in the Annapurna mountains in Nepal, he saw a
small school. All the children were outside. He looked though a window and
saw that inside the school was dark. The school had a sign that read: "We
have no teachers. If you want to stay and teach for a few days, we would
be very pleased."
Professor Irvine-Halliday says that experience had a big effect on him.
Back at the University of Calgary, he was on the Internet one day. He saw
a company in Japan selling bright white L.E.D.'s. So he built a light with
some. This is how he began the Light Up the World Foundation.
This non-profit group has provided lights to several thousand homes in
Asia and Latin America. Presently the foundation does not sell its
products to individuals. But it does sell to non-governmental
organizations and humanitarian groups.
Professor Irvine-Halliday says "we have a market that is very large."
He notes that about 2000 million people around the world live without
The Web site for the foundation is lightuptheworld.org.
This VOA Special English Development Report was written by Gary
Garriott. This is Gwen Outen.