'Twig light' project receives NCIIA funding

The National Collegiate Inventors and Innovators Alliance (NCIIA) recently awarded ASU College of Technology and Innovation professors Brad Rogers and Mark Henderson $16,000 to finalize the design of a device meant to bring electric light to villages in rural Africa. The project is part of the GlobalResolve social entrepreneurship initiative at ASU.

The device, called the “Twig Light,” was invented by graduate student Michael Pugliese, and consists of a wafer-thin thermoelectric generator sandwiched between a combustion chamber and a heat sink. To generate electricity, the heat sink is placed in a shallow pool of water to keep it cool, while small twigs are burned in the upper combustion chamber for heat.

“The temperature difference powers the generator, producing 5 volts of electricity – enough to run a bank of LEDs that can light a room,” said Pugliese, a mechanical engineering technology major.

A prototype of the Twig Light was demonstrated during the summer in the village of Domeabra, Ghana, where the residents received it with enthusiasm.

“We have received great support and comments about the Twig Light,” said ASU engineering technology professor Rogers. Rogers is the director of research and development for GlobalResolve, which sponsored the Twig Light’s development. “We left nine lights in Ghana for evaluation so that we can get comments and critique on their use.”

The lack of lighting in the village is one of their biggest problems, according to Pugliese. Central electricity is often expensive and unreliable in developing countries.

The Twig Light was developed as a project in a class in Village Energy Systems taught by Rogers for engineering and engineering technology students at the Polytechnic campus this past spring. The course focuses on design for extreme affordability – in other words, designing devices that are both useful and affordable for people living on only a few hundred dollars a year.

“There are no moving parts inside the generator, and most of the components can be manufactured and assembled locally in Africa,” said Pugliese. “The Twig Light can run on any readily available fuel. It can generate electricity from wood chips, twigs, ethanol or even coals from a cooking fire.”

Pugliese’s Twig Light design eventually will include multiple attachments to use electricity the device generates to run cell phone chargers and other electrical devices as well as produce light.

For now, Pugliese is working with Rogers and Henderson on an alternate design with improved reliability and lower manufacturing costs. He hopes to have the new design completed by the end of October and will be presenting it at the NCIIA’s 14th annual conference in March 2010.

His ultimate goal is to produce a simple, affordable and reliable design that will be assembled in the same rural villages where it is used, providing sustainable economic development in addition to light. The group is currently investigating companies in Ghana that can oversee production and marketing of the light for Africa.

“Buying products made overseas won’t help the villagers in impoverished areas,” he said. “We have to give them something that they can use to stimulate their economy.”

Kari Stallcop, (480) 727-1173
Public Affairs at ASU Polytechnic campus