LEDs Lighting Up the African Darkness

Peace Corps Online writes "In a non-electrified society, life is defined by the sun and little is accomplished once it sets around 6 pm. Only 19 percent of rural areas in Ghana have electricity. The rest use foul-smelling kerosene lamps to light their huts, which pollute, provide little light and are major fire hazards. But now Philips has partnered with KITE, a not-for-profit Ghanaian organization, to bring artificial light to villages that have no electricity. The new Philips products include a portable lantern which provides bright white light where it is needed, the Dynamo Multi LED self-powered (wind-up) flashlight that provides 17 minutes of light from two minutes hand winding, and the 'My Reading Light,' which is a solar-powered reading light with built-in rechargeable battery. 'People can now do things in the evening,' says Harriette Amissah-Arthur, KITE's director. 'If you could only see the joy these products bring the villagers. You look at their faces; you have to see it to believe it.'"

Comments

Biased article... phillips

[gravos]

This article is biased towards Phillips' contribution... Shouldn't there at least have been a mention of the "Light Up the World Foundation" and Dave Irvine-Halliday (U of Calgary)?

http://www.ucalgary.ca/oncampus/weekly/nov4-05/schulich-lutw.html

http://www.google.com/search?q=philips+lutw

I have tried it - use the meter correctly

[Kupfernigk]

You are totally wrong. You have to use an incident light meter, it's no good pointing a camera type light meter at the bulb because incandescents all have a bright spot while fluorescents spread the emission over a bigger area.

My own experiments, years ago, showed that in real world use CFLs are equivalent to about four times the wattage of standard 1000 hour incandescents, whereas full size fluorescents produce maybe 5 times the output of the same wattage incandescent. Linear 8W CFLs as used on boats and caravans give about the same actual illumination as a 20W tungsten-halogen bulb, because their light output is much less directional, but then they are much better at illuminating dark corners.

Case in point: when we moved to our present house, the kitchen used 3 100W bulbs. These have been satisfactorily replaced with 3 20W CFLs for the last 20 years. As different types of CFL have evolved, there has been no deterioration in light output, though it is important to buy good quality - GE or Philips - bulbs.

I note that the cost of LEDS is now becoming comparable in lifetime cost with CFLs. The main issue is that LED drivers are relatively inefficient because most of them waste a lot of power in series resistors. What is needed is a really efficient current driver IC for LEDs. This would drive up the efficiency of conversion and make them even more useful in the Third World.