Interview with Kazuaki Yazawa

With a thermoelectric technology, there is no need to carry bulky, heavy batteries, or charge your device.

I have been thinking of body heat recovery since the mid-1990s. Over a recent decade of academic research, I developed a generic method to harvest maximum heat energy with thermoelectrics. Woven fabrics were discovered to fill a need for a flexible energy conversion device.

The woven thermoelectric generator is a passive device, meaning that it - by itself - is a non-communicating, unhackable system. It is possible that any device, a woven thermoelectric device is connected to, could be prone to interference by electromagnetic fields but not the thermoelectric power system itself. Preventing unintended interference is critically important, especially for medical devices. We will work with any medical device partners to assure that all standards of testing protocol and independent validation are followed.

We have begun to discuss continued research with interested partners but have yet to formalise any final agreements.

This technology is still in an early stage of development. There will be a variety of future research to explore many types of fabrics and applications for fashion. At this point, a first step may be in sporting/athletic gear-to-wear or medical/health equipment. As the technology matures, there would be many opportunities to integrate with fashion and other areas.

There is no risk to a user at the level of electricity generated. The power output of a thermoelectric generator would be in the range of one or two coin/button battery(ies) common in wrist watches. There is no harm to touch well-sealed coin batteries, and there is even less risk from this generator. Furthermore, the device is electrically insulated by exterior polymer; so the surface of the skin will never touch any electricity, and unlike a battery it will never run out.

Monitoring local activity will help to develop the muscles effectively, which is important for an athlete. Sensing pressure, temperature, sweat, local muscle group pulse, etc, are all possible to monitor with a lightweight, battery-free device.

Do you know a Drink Comfort Grip? I imagine a product that looks somewhat similar. In theory, from 500 millilitres of hot coffee, 5 watts x 6 minutes (500mW) of electricity may be generated. This kind of energy conversion can enable charge of a small electronic device for one time emergency.

I hope, yes. The flexible power device could help to bring various electronics into clothing and fabrics and change the fashion quite a bit. Perhaps, your dress in the future may express something by LED, or changing its colour, or interactive displays, etc, to heighten personal expression, as an example.