MIT Chip Harvests Energy from Three Different Sources

DailyTech, Tiffany Kaiser, July 11, 2012 

Energy is harnessed from natural light, vibrations and heat

 (Source: energymicro.com)

MIT researchers have developed wireless computer chips that are capable of harnessing power from natural light, vibrations and heat.

Anantha Chandrakasan, an MIT professor, led the MIT team in creating the new computer chips. These chips have the ability to run at very low power levels and collect energy from all three above-mentioned ambient power sources.

The chip consists of a circuit that can collect from many different environmental sources of energy, such as vibrations from traffic on a bridge. Many chips need separate control circuits for each energy source because of certain requirements for the collection of each. Many circuits that harvest thermal energy produce about 0.02 to 0.15 volts while those that harvest from vibrations produce up to 5 volts.

However, this new chip from MIT can collect power from natural light, vibrations and heat -- all on one circuit.

Aside from the ability to collect energy from three different environmental sources, the chip can operate at low-power levels. It is able to do this using a dual-path architecture where the sensor can either be powered directly from the source or from a storage device. This makes it much more efficient, as it uses a single time-shared inductor, which helps operate multiple converters at once.

A circuit like this means a battery-free monitoring system, which could be applied to environmental sensors and biomedical devices at some point. Having energy harvesting capabilities in many environments can increase power from certain systems like wireless sensor nodes.

The chip is also helpful because only one or maybe two energy sources may be available at a given time. With three possibilities at once, this is no longer an issue.

Source: MIT