Nanotechnology is finding new and interesting applications all the time. A professor of nano-engineering at UCSD recently came up with bio-sensors integrated into underwear, opening up a lot of very creative possibilities. There are still many challenges in implementing nanotechnology, however. One of the keys is how to provide power for such small devices. The energy source and storage don’t have to be implemented at nano-scale as long as the energy can be conveyed to the nano-devices that will be doing the work. Where would the energy come from, how would it be handled and stored, and how will it be made available to the devices that need it?
Power generation is already available, though at much larger than nano-size. Tiny power generators using pendulums to make electricity from human movement were tried in the last couple of years, with some success. Such a machine was attached to a person’s pants at knee level, where normal walking generated measurable power. Pendulum-type energy collection devices have been used since before 1960 in self-winding watches, for example. Another possible source of energy is the well-known thermocouple. Such a device could be integrated into clothing and derive energy from the temperature difference between the wearer’s skin and the surrounding air, producing a small amount of electricity proportional to some degree to the difference in temperature.
Electricity storage can be accomplished through small batteries, of which many types are available, but there will be new options. Existing batteries come in a wide variety of shapes and sizes. New options being developed include batteries that self-assemble in a liquid, suggesting that in the future batteries might be created by treating fabrics with solutions of appropriate chemicals, or might be painted onto a surface. Connecting electrodes to them presents some challenges yet to be worked out if done at nano-scale, but using sheets of particular materials or weaving electrode materials into fabric presents possible solutions.
Chemical energy sources could be designed into fabrics or applied to surfaces. Chemical energy, like that in single-use batteries, or used directly to power nanodevices without an intermediate step as electricity, might do the job, but it would not be renewable unless the chemicals could be replenished, possibly through washing or an infusion process.
Can electrical nanodevices operate from broadcast energy? The relative scale of such devices might not present a problem if the energy field is strong enough for them to pick up enough electromagnetic energy to function. Small size might be countered by energy fields oscillating at extremely high frequencies, possibly near optical wavelengths. A knee-mounted generator might provide enough energy to create a field of RF that would power nanodevices within a few inches of it, for example, but that would be enough to monitor the wearer’s health in a number of ways, for example.
I intend to write more here, and include more links, and will do so as soon as I have time. Thanks for reading, and please feel free to comment. It is the collection and sharing of ideas that will provide a path to a sustainable future for us all. — Tim