Solar Lighting Showdown
Video below. Our quest for portable, rugged, solar-rechargeable lighting for refugee camp and village classrooms in Chad is down to a two-light showdown. The two contenders are 1) a new lighting system designed in partnership with electronics manufacturer AltusLumen and 2) the winner of our prior field tests of off-the-shelf equipment, the SOLUX-LED-50.
We sent a prototype of our new lighting system, shown in the video above, and seven more SOLUX-LED-50s to our partner CORD to bring to eastern Chad for the field tests. The equipment is now in place and we expect to have test results soon. The additional SOLUX units will help better determine the number that would be required per classroom and in different environments (indoors, outdoors).
The essential specs of the prototype system:
max lumens: 140
beam angle: 90 degrees
solar panel: 12W (folding)
power source: 6 AA NiMH 2200mAh (enclosed in battery pack)
Each light is designed to provide six hours on maximum brightness per charge, and the solar panel should be able to charge about two battery packs per day. (Although the prototype in the video shows one solar panel and only one light, the production version would come with two lights per panel.)
As shown in the video, the solar panel can easily be mounted directly on top of the carrying case, without using any tools, and can be adjusted to track the angle of the sun. This also keeps the panel off the ground, and provides a shaded place between the panel and case where the battery pack can rest while charge, to reduce the risk of overheating the batteries.
A very important aspect of the prototype's design is that the light itself consists of two separable units: an LED unit and the enclosed battery pack. Being able to separate the battery pack reduces the risk of theft during charging, allows the battery pack to power other electronics (such as a classroom audio system, also in development), and reduces replacement costs should damage occur. The battery pack has a metal bar that can easily be hung overhead or from a nail in a wall at an adjustable angle, as shown in the video. Combined with the wide beam angle and high brightness, this illuminates a very wide area.
The LED unit is based on an existing design by AltusLumen for their super-bright PAD-PRO light. The standard PAD-PRO was modified to increase the battery capacity and place the batteries inside a rugged enclosure that can be connected directly to the solar panel. This reduced development cost and time...
BUT amazingly there was no development cost for us, as AltusLumen has generously worked on this project pro-bono!
If you are in the market for a portable LED light, please keep their kindness and skill in mind and check out AltusLumen's offerings at www.altuslumen.com. Their off-the-shelf models are compact, lightweight, rugged, very bright, and have a wide-angle beam -- qualities we especially sought out. As an added bonus, their products are made largely from recycled and recyclable materials.
When we learn the results of the showdown between this prototype and the SOLUX-LED-50, we will be ready to start lighting the way to education for thousands of Darfuri refugees and Chadian villagers. To stay informed of developments, please subscribe to our mailing list.