The bright green energy future that surely awaits us exists in concept, but as we all know there are key pieces of technology that we still haven't quite figured out, like higher-capacity battery tech or better biofuel processing methods. Similarly, one of the key technology gaps hampering the U.S. energy grid is a lack of understanding regarding superconductors -- materials that can carry electricity with no energy loss. Now, DOE scientists may have cracked a critical part of the superconductor mystery, opening the door to a grid that can carry electrical current over great distances without drastic energy loss.
Superconductors only work at extremely low temperatures, rendering them practically useless because the energy used to cool them to those temps cancels out the benefit of no energy loss. For decades, researchers have tried to figure out why room-temperature semiconductors won't work. They knew it had something to do with electron behavior during the so-called pseudogap phase, a temp range where superconductivity breaks down.Now, the researchers think they've figured it out. During the psuedogap phase, electrons undergo a change in copper-oxide semiconductors in which the tunneling ability of electrons is different in different oxygen atoms. To quote the awesomely named Séamus Davis, the project leader and lead author on the Nature article describing the research:
"Picture the copper atom at the center of the unit, with one oxygen to the 'north' and one to the 'east,' and this whole unit repeating itself over and over across the copper-oxide layer. In every single copper-oxide unit, the tunneling ability of electrons from the northern oxygen atom was different from that of the eastern oxygen."
That asymmetry is key, and though it doesn't yet provide the key to superconductors, it is a significant start. Asymmetries in liquid crystals gave scientists the tools to manipulate them, and now LCD screens are cheap and ubiquitous. The DOE team hopes this breakthrough in understanding will similarly open the floodgates on superconductor research, culminating in room temperature materials that move power with no loss of energy.
That would not only make energy cheaper, but would make it possible to pipe renewable energy from places that are windy and sunny to places that are not, or to move surplus power over long distances to places that are low on juice so that a natural gas plant doesn't have to kick into action.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.