Well as I promised earlier, I should explain the magical panacea known as Superconductors. So let me begin by outlining electricity flow and why the power infrastructure around the world is set up as it is. The easiest example (somewhat obviously) is the United States and the national power grid. The National Power Grid (or NPG) is basically one big wire that stretches to most parts of the United States, rural and urban through three major grids, known as the Western Interconnection, the Eastern Interconnection, and the Electric Reliability Council of Texas grid (ERCOT). The names of the grids imply what areas they cover, with the ERCOT grid covering most of the state of Texas by itself.
I won't go into detail with how exactly power is generated in the U.S., as this ranges both by grid and by geographical area, but a majority of power generation is from fossil fuels (usually coal) and is distributed over high-voltage wires across the nation. If you've ever heard the phrase "high-voltage wire" there is a reason why it is high-voltage. Electricity has certain rules that apply to it, one of them being Ohm's Law, which states that Resistance (R) = Voltage (V) / Current (I) [R = V/I]. This can be applied largely in two ways: one being the calculation for the instantaneous resistance in any component in an electrical circuit, the other being a representation of power lost over a circuit. Considering that power is simply voltage times current, that means that the voltage is always proportional to the current with a constant power supply. Therefore one could rearrange the two formulas to calculate the power lost due to resistance (incidentally this equals R(I^2)). From this we can say that the lower the current flowing through a long-distance conductor, the better. So for this to occur, the power coming from a generator must be "stepped up" (which means using a transformer to multiply the voltage), so that there is a low current running through a power line with a high voltage.
For a long time, society and engineering has focused on altering the power itself to modulate the power lost due to resistance. However, one has to remember that there are always two sides to these types of equations (hence the 'equals' sign). So, if we can change the voltage-current ratio to satisfy a certain resistance, why can we not change the resistance to satisfy the voltage-current ratio? Actually, we can. Fairly easily. Resistors run in all ranges basically, depending on the materials used in them (which could potentially be any element in the periodic table). We know how to eliminate all or close enough to all of the current in a circuit (besides breaking the circuit or directly grounding it), that just involves getting a combination of elements that has almost no conductive structure (not too hard). However, it is the exact opposite that eludes us.
So what is it that makes it so hard to lose all of the resistance if it's easy to find materials that have such a high resistance? The secret is in the atomic structure. Essentially, one can visualize the atoms in a substance in a lattice structure, where there is something closely resembling a large number of cubes fit together into a grid (NB: This is purely for explanatory purposes, the actual visualization is much more complicated to explain). Atoms themselves behave differently depending on the state of matter. Atoms in a gas aren't even really coherent to each other (in an Ideal Gas). In a liquid, atoms have some intermolecular loose bindings, where they stick together, but still can be separated easily (you can remove a cup of water from a pool with little effort to separate the two). Solids are much harder to do so. In solids, atoms are tightly packed and in a fairly regular structure. The intermolecular forces are strong, so it's not easy to pull a hefty stick apart. It's mildly easier to break it in half, but the wood does not break smoothly, and even so it's nigh on impossible to snap a full-sized tree in half with your bare hands (where as its still just as easy to grab a cup of water from an ocean). One can imagine that an electron will travel through a substance as long as it has some sort of ordered structure, and the more ordered it is, the easier the electron will go through it. Organic solids (e.g. wood) do not really conduct electricity even though it is a solid because the organic molecules are so complex and because it is not comprised of electrically conductive materials. Electrically conductive materials are not dependent on how solid they are, so simply finding the most solid material will not reduce resistance.
There is one way we know of right now that will reduce resistance beyond natural occurrences. There is another state of matter (actually there are two, the other being plasma) beyond Solids, called the Bose-Einstein Condensate (or BEC). A BEC revolves around the concept that theoretically an object or material can be cooled to the point that the atoms inside of it do not move at all (i.e. no kinetic energy from translation, rotation, or vibration). A BEC would essentially take an electrically conductive material and perfect align that "lattice" structure such that an electron could pass through it ideally uninhibited. There are problems with BECs at the moment, the most important being that to achieve this low state of kinetic energy, a material must be cooled as much as physically possible (most materials enter the BEC state near 0-degrees Kelvin or Absolute Zero). Scientists have shown that many electrically conductive metals when super-cooled will become something called superconductors, where the resistance is almost or even wholly nonexistent. The issue is that cooling materials to those temperatures is incredibly expensive. The dream relative to superconductors in the near future is to discover a material or compound that achieves this state at room temperature (hence room-temperature superconductors). Currently we implement superconductors that can operate while being cooled by large amounts of liquid nitrogen. While this isn't the perfect solution, it is mitigated by the fact that a gallon of liquid nitrogen is cheaper than a gallon of milk. So for example using super-cooled materials to create an incredibly strong magnet (e.g. CERN particle accelerator) is a relatively practical and cost-effective solution.
So what would the effects of discovering a room-temperature superconductor be? Anything from electricity cheaper than dirt to flying without wearing anything on your body. Yes, since everything exhibits a minor magnetic field, a room-temperature superconductor could easily create the strongest magnetic field imaginable that could easily keep a person floating in midair. Superconductors are, in my opinion, one of the most important technologies to focus research on going into the next decade.
Closing note: I'm sorry about the delay in posts, I promise to try harder to keep pumping out material when possible!
As always, thank you,
--J
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