HARVESTING ENERGY

The energy harvest here is now far too small for transportation or to power the home. It will still be New Energy when we are all bionic or absorbed by the Borg. See the lengthy article for scientific details and details on company contacts.

Race is on to develop energy harvest ICs
Christopher Hammerschmidt, October 10, 2007 (EE Times Europe via Embedded)

WHO
Jrmie Bouchaud, Wicht Technology Consulting; Marco Voigt, Autonomous Microsystems research program, VDI/VDE Innovation + Technik; Peter Spies, Fraunhofer Institute for Integrated Circuits (Fraunhofer IIS); IMEC Netherlands (researcher Bert Gyselinckx); Perpetuum Ltd (Roy Freeland, CEO); EnOcean GmbH

Schematic of the piezo electric concept: Vibrations are absorbed and the energy is transferred to a wireless sender. This concept is used in medical equipment monitors. (click to enlarge)

WHAT
- Energy harvesting (aka energy scavenging): The environment itself supplies the energy required to power intelligent autonomous devices through temperature differences, vibrations, or light.
- There are 2 kinds: macro- and micro-energy harvesting.

WHEN
- On the verge of developing a market with a multi-billion dollar potential.
- Macro harvesting already being used on an industrial scale.
- Piezo – 5 years.
- Tire Pressure Monitoring System (TPMS) will take off about the year 2012.

WHERE
aircraft construction, personal health care monitoring systems, burglary detection systems

WHY
- The breakthrough for energy harvesters is yet to come. Very little energy harvested presently and consumed by data transmitting but the German federal government has put up $685 million in research support program
- Many techniques: temperature differences, light radiation, electromagnetic fields, kinetic energy
- Fraunhofer IIS: semiconductor-based thermo electric generator (TEG) transforms temperature differences into electrical energy. Worn on the body, the device can power medical monitoring devices. It uses the Seebeck effect (temperature differences across a pair of conductors into electrical energy). The temperature difference between the human body and the ambient generates very small voltages.
- IMEC uses the piezoelectric effect = mechanical vibrations into electrical energy. 40 microwatts. Material of choice is lead zirconate titanate (PZT) but this material is very difficult to handle in mass production.
- Perpetuum Ltd already has energy harvesters in industrial production: power sensor nodes that monitor machinery conditions in the petrochemical industry and other pump works wirelessly.
- EnOcean GmbH: electro-dynamic energy converters linked wirelessly to power switches. The energy to push the button is transformed in electrical energy for a wireless transmitter that triggers the circuitry to turn on the light in a room. A toy for architects? The company has already sold tens of thousands of units.
- The most significant market for this technology in terms of volumes is likely to be tire pressure monitoring systems (TPMS). MEMS technology. Intelligent tires could transmit data on tire pressure, traction, wear, temperature and much more.

The many applications of EnOcean GmbH's "architectural toy." (click to enlarge)

QUOTES
- Spies, Fraunhofer IIS: "One theoretically could connect several Seebeck elements in series, but then it would become too clumsy…We have developed a circuit that starts working even at 50mV, which makes it possible to turn very low temperature differences into electrical energy…"
- Roy Freeland, Perpetuum: "We primarily use energy from vibrations to turn them into energy by means of a coil-magnet system…The issue is to achieve a good bandwidth…You need a device that picks up over the entire frequency range…Our definition is that kinetic energy has very low frequencies of about one hertz, the frequency of a heartbeat, for instance…"