Three university students in Santiago, Chile have developed a plant-powered device to charge their mobile phones. The three engineering students got the idea for the device while sitting in their school's courtyard. Their invention is a small biological circuit they call E-Kaia. It captures the energy plants produce during photosynthesis. A plant uses only a small part of the energy produced by that process. The rest goes into the soil. E-Kaia collects that energy. The device plugs into the ground and then into a mobile phone. The E-Kaia solved two problems for the engineering students. They needed an idea for a class project. They also needed an outlet to plug in their phones. One of the student inventors, Camila Rupcich, says the device changes the energy released from the plant into low-level power to charge phones. The E-Kaia is able to fully recharge a mobile phone in less than two hours.