VOA常速英语:Chilean Students Find 'Green' Way to Charge Phones

As free as they make us, mobile phones still need to stay close to a power source. Soon that may change with “green” power.

Three Chilean students got the idea for a plant-powered device to charge their cellphones, while sitting in their school’s outdoor courtyard during a break from exams, with dead mobile phones. Then, one of them had an “aha” moment.

"It occurred to Camila to say about plants, "said inventor Evelyn Aravena. "'Why don’t you have a socket, if there are so many plants?' After that, we thought, 'why don’t they have a charging outlet? Because there are so many plants and living things that have the potential to produce energy, why not?'”

Their invention - a small biological circuit they call E-Kaia - harnesses the energy plants produce during photosynthesis.

A plant uses only a fraction of that energy - the rest goes into the soil, and that's where the E-Kaia collects it.
The device literally plugs into the ground and then into your phone.

“It’s the most amazing project I’ve ever seen in my life, plain and simple. They brought the prototype, the prototype worked - and that’s when it all changed, at least from my personal point of view and I began to support them. It was transformational," said Mauricio Cifuentes of Duoc University.

The device solved two problems for the engineering students – they needed an idea for a class project, and an outlet to plug in their phones.

“Looking for a place to charge the notebook, which had no energy, and the mobile phones, we weren’t able to find anything because all the other students were in the same state of madness trying to find a place to charge their devices," said Aravena.

But plants are everywhere, and the biocircuit taps into their excess power.

“There is a complete energy cycle of the plant. We decided to incorporate into the cycle, then we would not affect the plant’s growth. The biocircuit makes an acquisition and that is transformed into energy to later make charges for low consumption," said inventor Camila Rupcich.

The E-Kaia doesnt' carry much charge but it's powerful enough to completely recharge a mobile phone in less than two hours.

The student inventors have applied for patents on their technology, and expect the E-Kaia to go on sale in December 2016.