Before you read this, close the door, draw the curtains, and turn out the lights. If you are reading on your laptop, momentarily close the lid.
Now that you are back, think about how it felt. Chances are it was not too disorientating or frightening. After all, you were in a familiar room with a light switch close by.
Now imagine that days earlier there had been a massive earthquake. Thousands are dead. Entire towns have been flattened. Resources are in short supply and something as simple as turning on a light is not an option,
Two years ago, that was the situation in Haiti, following a catastrophic quake. The country's infrastructure, already minimal, was badly affected.
But along with the influx of aid agencies, technologists, engineers and designers all offered their help to Haitians to try and rebuild their homes and their nation. One of them was Andrea Sreshta, who was working toward her master’s degree in architecture at Columbia University in New York.
She immediately spotted an area where she could help.
"Lighting was something that seemed a little bit overlooked," she said. So for a class project on designing around disaster, Sreshta teamed up with classmate Anna Stork, who had a background in engineering. Together, they decided to create lighting for the thousands of Haitians living in the so-called "tent cities" that sprang up around the country, particularly on the outskirts of the capital, Port-au-Prince.
"We read stories about how people felt very unsafe at night, especially women and children," says Sreshta. Given Haiti's shaky electricity grid, the two women turned to the idea of solar power. They designed a number of solutions, large and small, but one idea really stuck; a small solar light they called Luminaid.
The idea, like the product itself, couldn't be simpler. Luminaid is an inflatable plastic bag, about the size of a small pillow. In an exterior pocket, Sreshta and Stork fitted a solar cell, a rechargeable lithium-ion battery, and one single LED. It has one switch, which can be set to off, low and high. Depending on the sunlight, the battery can fully charge in two to three hours. On the low setting, Luminaid can give light for about six hours. On the high setting, it lasts around four hours.
The Luminaid light is also waterproof, meaning that the unit can float. The plastic itself can be printed on, which means instructions can be written directly on to the product itself.
But the Luminaid's distinguishing feature is the handle. When it is inflated, it can be hung or carried easily. Stork explains: "We heard that in the tent cities people really wanted something they could easily take to the latrine at night, so it was very handy to have a handle to carry it around."
There are, of course, other low-cost solar lighting solutions for disaster situations out there. Glowstar makes a solar lantern, while d.light makes a solar flashlight and Nokero a low-cost solar light bulb. But Sreshta and Stork think that Luminaid has certain advantages. For starters, they say, the uninflated lights can be packed, shipped and deployed to affected areas much more efficiently than lanterns or flashlights. Fewer moving parts mean less breakage during transport. Those factors, say Stork and Sreshta, could make the product attractive to NGOs working in disaster areas.
Luminaid has gone through limited field testing. Professors from Columbia took some of the lights to Haiti to get feedback, while Stork and Sreshta themselves went to test the lights in India.
"Kids loved it," says Stork. "We visited a lot of schools and a lot of orphanages. Children were just so excited about the prospect of having their own light to study with."
But the children also provided valuable feedback. They all wanted it to be brighter, Stork says, so she and Sreshta looked at ways to change the positioning of the LED to provide better light without adding an extra bulb. "There's always a balance between keeping the cost really low, and also making it competitive with some of the similar solar lanterns that are out there in terms of its brightness and performance," says Stork.
For example, the pair originally wanted to use a flexible solar panel, but it drove the cost too high, so for now they are using a rigid panel. Stork and Sreshta estimate that, in volume, they can get the cost of each Luminaid unit to below $6. The d.light, in comparison, is around $10.
There are, of course, questions about durability. The lights need to be designed to go into some very difficult situations. Stork and Sreshta say the Luminaid is designed to last, with heavy use, for about two years. And disposal? Well, you would just throw it away.
When I asked them if they worried about used Luminaid lights eventually lining roadsides around the globe as litter, they admitted it was a concern and said they were working on a new design that would incorporate biodegradable plastic.
The team are also looking at ways that the Luminaid can be used in situations beyond natural disasters. With more than a quarter of the world's population without access to electricity, there seems to be plenty of room for a low-cost lighting product like LuminAID. They also don't see any reason why their product could not be sold in outdoor stores, and used by hikers and campers.
Luminaid just completed a funding drive on the crowd funding platform IndieGoGo. The project asked for $10,000, but raised more than $51,000. Taking inspiration from the low-cost computer project One Laptop Per Child’s “give one, get one” campaign, they also ran a "give light, get light" campaign – if you bought a LuminAID light for someone in the developing world, you got one for yourself as well.
Individuals in 25 different countries bought lights, and more than 3,000 units were distributed to 10 organisations in Africa and Asia.
Not bad for a student project.
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