Access to on-demand lighting is a given for many of us, but some developing countries don't have the proper electrical grid set up to allow even a basic light bulb to turn on. Solar power is a popular way to address this problem, a concept we recently explored in our FLAP bag project series. Now Danish researcher Frederik Krebs has designed an ultra-cheap lamp that combines LEDs, lithium batteries, and photovoltaic cells.

Printed sheets of photovoltaic cells aren't new, but Krebs is the first to stick LEDs inside the panels, which resemble a lamp when rolled up. The LED/PV combo is cheap--a single unit is expected to cost just $7--though it isn't particularly efficient. Krebs claims, in fact, that he uses the worst PV technology available. But that's precisely what makes the lamp so cheap.

Even though the lamp only lasts for a year, villagers can afford to replace it, especially since the lamp can cut annual lighting costs in villages by up to 75%. Considering that average off-grid villagers in Africa, Asia, and Latin America spend an average of $40 to $80 yearly on soot-dispersing kerosene lights and candles, Krebs' lamp is a sustainable bargain.

Krebs already tested his lamp successfully in Zambia this summer, and further testing will begin in Mali and Malawi this winter. The lamp will hit store shelves next year.

[Via Popular Science]