2004-10-31
This is Gwen Outen with the VOA Special English Development
Report.
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 nineteen ninety-seven, 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 two thousand million people around the
world live without electricity.
The Web site for the foundation is lightuptheworld.org.
This VOA Special English Development Report was written by Gary
Garriott. This is Gwen Outen.