Charge your mobile phone with wi-fi: the idea of a Spanish MIT engineer.

It may sound almost utopian, but today it is possible to ensure that we are getting closer and closer to forgetting the hated porters once. No, it is not that we are going to eliminate all the devices that currently depend on a battery, but in a few years it will be possible to always have those batteries charged and their energy recharged autonomously. At least that is the idea of ​​the Spanish engineer Tomás Palacios and his colleagues who have just launched the first flexible device capable of converting wifi signals into electricity and bring that energy to the batteries of electronic devices. The invention has been made public in the journal Nature through an investigation in which they explain how they have come to create this 'rectenna' (that's the name of antennas capable of converting electromagnetic waves into electricity). The name is not new because these antennas, as you can see in different publications, have been studied for years, but the difference is that this is the first invention of its kind capable of capturing energy and transferring it to any electronic device without needing of a large structure or rigid elements. The best way to understand the value of this idea is to know how it works. The new antenna picks up the wifi signal, with it is then connected to a new device made of a two-dimensional semiconductor. The signal travels in the semiconductor, which converts it into electricity that could be used to power electronic circuits or recharge batteries. In addition (here is one of the great advances of researchers), the material of the device makes it flexible and can be manufactured in large quantities. The idea is not only to load your phone, but to feed large infrastructures throughout the planet.

"And if we could develop electronic systems that involve a bridge or a road and thus bring artificial intelligence to everything that surrounds us? How would we provide energy to those systems?", Explains Tomás Palacios, researcher and professor in the Department of Electrical Engineering and IT of the MIT. "What we are presenting is a new way of feeding the electronic systems of the future using the energy harvesting of wifi signals, an invention that can be easily integrated into large areas." The first promising applications for the 'rectenna' include the feeding of portable electronic devices, medical tools, and sensors for the 'Internet of things'. In the experiments, the device created by Palacios and his team has shown that it can produce around 40 microwatts of power when exposed to typical Wi-Fi power levels (around 150 microwatts). That is more than enough energy to turn on the screen of a mobile phone or a silicon