About the author
Jonathan de Roo
Hi everyone, in my previous post I explained how we can use certain nanoparticles to harvest solar energy. But that’s only one part of the story. However important it may be to find new energy sources, equally important is energy saving. The more so as some new energy sources like wind and solar energy do not provide a constant flow of energy.
Hence, the power supply will become more and more dependent on how sunny or windy the day is.
Unless we find solutions…
Please meet: superconductors.
These fascinating materials are able to conduct electricity without any resistance or losses. Can you imagine the benefits of such materials? We could make more efficient transformers, high megawatt wind turbines, new energy storage devices and many more. All applications in which superconductors are integrated have reduced energy losses. Besides which, superconductors are also super magnets. In the following movie, an application of this remarkable property is illustrated: the levitating train.
So the number of applications is huge, but are there any drawbacks?
Well, the first generation of superconductors needs to be cooled with liquid helium to -269 °C. Helium is scarce and expensive so, at this moment in time, superconductors are almost exclusively used in MRI scanners in hospitals and other high tech applications.
Luckily, the second generation superconductors — the so called High Temperature Superconductors — are already being developed. The most researched material is yttrium barium copper oxide (YBa2Cu3O7). It becomes superconducting at “already” -181 °C. Now, this still may seem to require an awful lot of cooling… But just consider that liquid nitrogen has a temperature of -196 °C and is even cheaper than coca cola. So liquid nitrogen as a coolant is definitely feasible.
Final problem: in a lot of applications, the superconductor needs to work in a high magnetic field. But then… superconducting tornados arise, vortices in scientific terms, see figure below. These tornados are only three nanometres in diameter but there are a huge number of them. As long as they stay put, we have no problem. However, from the moment you inject a current into the superconductor, the tornados start to travel around, effectively destroying all superconducting properties.
The solution is simple:
homogeneously distribute three nanometre particles in the superconductor. The particles settle in the tornados and immobilise them. But this is easier said than done. Researchers all over the globe (including myself) are trying to find the best way of introducing the particles into the superconductor! I’ll keep you guys posted!