New 80pc solar-efficient chip aims to power IoT future

23 Jun 2015

With the aim of heralding in the realisation of an internet of things (IoT) future, a team of researchers has revealed its new solar-harvesting chip, which can achieve 80pc efficiency to fuel low-power sensors for years on end.

In order to achieve a situation where a country’s infrastructure, transport and household goods are all communicating with each other, it is understood that we will need to have millions of tiny low-power sensors that won’t need to be regularly changed so as to make them as efficient as possible.

That is why researchers from the Massachusetts Institute of Technology (MIT) have been feverishly working away on a new solar-harvesting chip to power this revolution that they say will not only power devices for a number of months, but can power itself.

This new achievement of 80pc efficiency is by far the largest to-date, with previous similar models only achieving an efficiency score of between 40pc-50pc.

Furthermore, according to MIT, the predecessor to the latest model could only use a solar cell to either charge a battery or directly power a device.

This new chip can do both, as well as powering the device directly from the battery.

A lot done, more to do

Led by Dina Reda El-Damak, an MIT graduate student in electrical engineering and computer science and first author on the new paper, her and her team’s circuit’s chief function is to regulate the voltages between the solar cell, the battery, and the device the cell is powering.

However, she said that despite these advances, there are still improvements to be made.

“We still want to have battery-charging capability, and we still want to provide a regulated output voltage,” she said.

“We need to regulate the input to extract the maximum power, and we really want to do all these tasks with inductor sharing and see which operational mode is the best. And we want to do it without compromising the performance, at very limited input power levels — 10 nanowatts to one microwatt — for IoT.”

Energy-efficient chip image via Shutterstock

Colm Gorey was a senior journalist with Silicon Republic