LEDs Lighting Up the African Darkness 182
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.'"
Where can I get mine? (Score:5, Interesting)
This isn't the first product Philips have produced for developing countries.
See wood-burning stove: http://www.research.philips.com/newscenter/archive/2006/060227-woodstove.html [philips.com]
I wish they would make them available to buy in the developed world though. I'd love some of this gear for outdoor pursuits.
Re:At the same time, European Union bans incandesc (Score:5, Interesting)
Well, that's because the LEDs actually are missing (large) components of the spectrum!
Even when your eyes are tricked into believing the light is white (by equally stimuling the three kinds of color-sensitive cells), the light reflected off of objects isn't "correct".
Imagine two green objects. One has true green pigment, the other has a mixture of yellow and blue pigment. Both look the same under incandescent light, because the light from a glowing filament emits a full spectrum .
When an LED doesn't emit a full spectrum the two objects don't like alike. The "true" green objects only reflects "true" green, not yellow + blue. The "yellow + blue" object doesn't reflect "true" green.
That's why it's hard to see in such light.
Your eyes (or brain) can adapt very well to changes in color temperature (yellowy incandescent light, or the blueish halogen light), but it can't cope with holes in the spectrum.
This goes for compact fluorescent lights as well, even as they keep getting better. The cheap ones are really crappy in this respect.
For fluorescent tubes there is a rating [wikipedia.org] for color temperate and color rendition. It isn't used (as far as I know) for compact fluorescents as they score way to low on this scale. That would make the public relations department of the manufacturers unhappy.
Re:Oh come on, where's the 100W LED in an E27 sock (Score:1, Interesting)
1000lm LED packs exist, although not in E27 socket format yet. A 100W LED would be much too bright for most applications (brighter than a 300W halogen lamp).
The "hazardous mercury" is pure scaremongering. Fluorescent lights are the primary light source in many work environments and they cause no problem. CFLs are just small fluorescent tubes with built-in starter electronics. In places where most electricity is produced by burning coal, the mercury pollution caused by incorrect disposal of fluorescent tubes is less than the mercury pollution from the coal.
CFLs can instantly provide 70% of their target brightness. If you choose your CFLs such that the power on brightness is sufficient for your application, you get an extra 50% after a few minutes and still save power and money.
Re:Gunfire (Score:3, Interesting)
He's probably in the Congo.
Ghana is actually one of the most stable countries in Africa. One that has just finished it's third General Election [guardian.co.uk] (with universal suffrage too) this year. It's first was in 1992, with 1996 letting the same guy in again. But considering it spent most of the 20th century ruled by a military Junta, it's come along way.
Re:At the same time, European Union bans incandesc (Score:2, Interesting)
What's wrong with Halogen Bulbs? (Score:3, Interesting)
Halogen light bulbs use tungsten filaments, JUST LIKE ORDINARY BULBS.
Two main differences:
- The filament is run at a much higher temperature, resulting in higher efficiency (around 20%).
- The gas inside the quartz "bulb" (the inner bulb, if you're buying a large bulb as a replacement) is a halogen gas (thus the name). These molecules combine with tungsten evaporated from the filament and effectively redeposits the tungsten on the filament. This results in longer lifetime.
End result: Longer lasting bulb, higher efficiency, roughly same environmental impact as normal bulb during production and disposal, still incandescent light (so no gaps in the output spectrum).
The one downside to halogen bulbs is that they get a lot hotter. Why? They have lower heat output, right? Yes, they do, but the AREA is a lot smaller due to the close proximity of the quartz. An outer bulb, such as typically present in a large-format "normal bulb replacement" (E26 base in the US), reduces this problem to about the same as for an ordinary bulb.
Re:Very cool. (Score:4, Interesting)
The OLPC was justified on a purely financial basis. The OLPC replaced heavy physical textbooks which require expensive physical distribution with one time laptop physical distribution and then electronic distribution of textbooks. Furthermore, in addition to the financial win, the textbooks could be updated with no distribution costs, they could be in the native language, and the students no longer had to carry all those heavy textbooks on their miles long walks to school; they had all their textbooks in one container, lightweight, with them at home and at school.
Regardless of how incompetent the OLPC management was, the laptop itself was fully justified on the financial basis alone, and the side benefits were a tremendous side benefit.