The quest for superconductivity at room temperature continues.
Superconductivity, the property of a material to conduct electricity with no resistance al all, was discovered over hundred years ago, back in 1911 by a Dutch physicist, Heike Onnes. It is the holy grail of power distribution. Resistance is bad because:
- it wastes power (some 5 to 6% lost in the distribution network, the grid – watch the clip)
- it heats the conductors (those on the grid and those inside the various motors and appliances…) thus limiting the amount of power that can be used
- it requires more material (the bigger the conductor the lower the resistance)
Hence, it is a no brainer that the use of superconductors (those materials having superconductivity characteristics) is the
way to go. The problem is that this properties pops up only at very low temperatures. When it was discovered it required temperatures very close to the absolute zero (-273.15 C, 0 K) but in the last fifty years, as shown in the graphic, researchers have been able to discover materials with superconductivity properties at higher temperatures.
The progress that has been made in achieving superconductivity at higher and higher temperature (the goal is to have it at room temperature, getting rid of the need to refrigerate the cables) has required the quest for new compounds and the use of very high pressure. When “squeezed” the atoms wiggle a little bit less (if you allow me this image of wiggling atoms…, let’s hope no physicists read this) and it becomes easier to deliver superconductivity.
Recently, researchers at the University of Rochester and the University of Nevada, Las Vegas, have demonstrated superconductivity at room temperature, 15C, in a lanthanum hydride compound. The good news is tempered by the need to apply a gigantic pressure, 2.6 million times the atmospheric pressure at sea level.
So on the one hand we have compounds that could -in principle- be used at superconductors but we need to freeze them at impossible low temperature (hence the need for huge amount of power to do that) or we have compounds that we an use at more reasonable temperatures (requiring limited power to ensure those) but they need to be squeezed at impossible pressures (that in turns require very huge power). Additionally, notice that it is not just about the power that would be required (to achieve low temperatures or high pressure), it is about the practicality (impossibility) of achieving that in the field.
Are we stuck?
Well, there is hope. Researchers are now investigating possible compounds using software. Rather than having to create a compound and test it they are now using artificial intelligence to discover compounds that might have superconducting properties and simulate their behaviour in the cyberspace. This is both way faster and cheaper!
The whole are of digital alloys, that is compounds being designed by software, is in rapid evolution an we might expect significant results in this decade.