It may be tempting to use this for "unlimited energy" but this is wildly impractical. Transmitting power is difficult because there are always losses (either losses in the transmission line or in the storage for physical transport). It would only be feasible for nearby uses but definitely not even the entire US, let alone the world.
Because these have to be physically moved and they cannot fit through themselves, they have limited practicality for things on a world scale except for hotspots or for scientific advancement.
The two biggest uses I can see are (1) military transport to war zones and (2) getting into orbit.
The former is still somewhat limited in its usefulness, especially with the probability of it falling into enemy hands.
The latter is significant, especially since it would become trivial to construct a larger space station, which would significantly improve both scientific research and microgravity-based medicine. It would also make intercontinental travel easier, at least from a single location, as you can construct recently vehicles in orbit, load them, then drop them off.
This, IMHO, would be single most important use of this technology in the world because it can directly help the entire world practically.
If, however, you must refrain from military and scientific purposes, there are some other alternatives, most notably in the form of transportation.
There are some extraordinarily expensive medicinal machines and it would be great if we didn't have to build so many. If two hospitals were linked (say one in central US and one in London), they could share resources between entire continents so each hospital only needs half the equipment it would ordinarily need. They would also have faster transportation to hospitals near the other hospital, further decreasing equipment requirements. This may be one of the more significant uses of a point-to-point static link.
Math behind transmission line losses:
To show you the kinds of things I'm talking about with transmitting that energy, let's say you have this awesome generator in New York City and wish to replace the Palo Verde Nuclear Generating Station in Arizona. Yes, this is a contrived example because you'd realistically put the generator in a better location, but this is just looking at a single replacement of a single generator; doing this on a nationwide or worldwide scale would be enormous, so let's just look at one transmission line.
If your cables were as thick as the cable bundles on the Golden Gate Bridge but were solid copper and your transmission line was at
765kV (the highest I could find), your cable incurs
4.675MW of losses, which is small compared to the
3937MW generated by the station you are replacing. If the cables were half that thick, it would waste
18.7MW, which is still small. If you somehow had a dialetric that could handle
2000kV lines, your losses are
2.736MW respectively, both manageable.
Except that your small cable (
2.031e10kg) just consumed more than the 2014 worldwide production of copper (
1.87e10kg). Congratulations. If you think drilling for oil is hurting the environment, just wait until you have to produce that much copper.
Sure, this line could be thinner because it can handle the losses (basically trading wastefulness in mining with wastefulness in heat generation) but this is just ONE line. A number I found shows that the US, in 2011, had an overall summer production of
1000GW of power - three orders of magnitude higher. Incidentally, if half of that were transmitted by the thicker line (and at least half will have to in the US), your line losses are
11GW and it weighs
Ok, so we get this from other planets... Except that the space shuttle with its boosters at launch weighed
1.99e6kg and that was HUGE. We don't have the ability to support an extraterrestrial mining operation, let along get all that copper back here. So that's right out.
And this was just for the US.
You could theoretically instead use this to power a plant to store energy by either generating hydrogen from the oceans or creating hydrocarbons, but these produce a lot of heat in the re-generation of electrical energy later, not to mention the volatility of hydrogen or the gaseous emissions of the hydrocarbons.
You could absolutely use this for free energy, but the bottom line is using the energy would be significantly more destructive than keeping our distributed power supply system.